From: Kevin Day <thekevinday@gmail.com>
Date: Fri, 7 Dec 2018 04:57:49 +0000 (-0600)
Subject: Progress: continue development on database abstraction
X-Git-Url: https://git.kevux.org/?a=commitdiff_plain;h=085545ff0e63c0e4802de6f397afd2be4e24384c;p=koopa

Progress: continue development on database abstraction
---

diff --git a/common/database/classes/database_alter_aggregate.php b/common/database/classes/database_alter_aggregate.php
index f3d9535..51dbb8c 100644
--- a/common/database/classes/database_alter_aggregate.php
+++ b/common/database/classes/database_alter_aggregate.php
@@ -186,6 +186,10 @@ class c_database_alter_aggregate extends c_database_query {
   /**
    * Get the total aggregate signatures.
    *
+   * @param int|null $index
+   *   (optional) Get the aggregate signature at the specified index.
+   *   When NULL, all aggregate signatures are returned.
+   *
    * @return c_base_return_int
    *   The total number of aggregate signatures.
    *   0 with the error bit set is returned on error.
@@ -278,7 +282,6 @@ class c_database_alter_aggregate extends c_database_query {
       $aggregate_signatures = ' *';
     }
     else {
-      // [ argument_mode ] [ argument_name ] argument_type [, ...]
       foreach ($this->aggregate_signatures as $aggregate_signature) {
         if ($aggregate_signature instanceof c_database_argument_aggregate_signature) {
           if (is_null($aggregate_signatures)) {
@@ -294,7 +297,6 @@ class c_database_alter_aggregate extends c_database_query {
       }
       unset($aggregate_signature);
 
-      // ORDER BY [ argument_mode ] [ argument_name ]  argument_type [, ...]
       $order_by_signatures = NULL;
       foreach ($this->order_by_signatures as $order_by_signature) {
         if ($order_by_signature instanceof c_database_argument_aggregate_signature_base) {
@@ -321,15 +323,15 @@ class c_database_alter_aggregate extends c_database_query {
       unset($order_by_signatures);
     }
 
-    $value = NULL;
+    $value = $this->p_do_build_name() . ' ';
     if (is_string($this->rename_to)) {
-      $value = $aggregate_signatures . ' ' . $this->p_do_build_rename_to();
+      $value .= $aggregate_signatures . ' ' . $this->p_do_build_rename_to();
     }
     else if (is_string($this->owner_to)) {
-      $value = $aggregate_signatures . ' ' . $this->p_do_build_owner_to();
+      $value .= $aggregate_signatures . ' ' . $this->p_do_build_owner_to();
     }
     else if (is_string($this->set_schema)) {
-      $value = $aggregate_signatures . ' ' . $this->p_do_build_set_schema();
+      $value .= $aggregate_signatures . ' ' . $this->p_do_build_set_schema();
     }
     else {
       unset($aggregate_signatures);
@@ -339,7 +341,6 @@ class c_database_alter_aggregate extends c_database_query {
     unset($aggregate_signatures);
 
     $this->value = static::p_QUERY_COMMAND;
-    $this->value .= ' ' . $this->name;
     $this->value .= ' ' . $value;
     unset($value);
 
diff --git a/common/database/classes/database_alter_coalation.php b/common/database/classes/database_alter_coalation.php
index 4137abc..27604ca 100644
--- a/common/database/classes/database_alter_coalation.php
+++ b/common/database/classes/database_alter_coalation.php
@@ -133,20 +133,20 @@ class c_database_alter_coalation extends c_database_query {
       return new c_base_return_false();
     }
 
-    $value = NULL;
+    $value = $this->p_do_build_name();
     if (is_bool($this->refresh_version)) {
       if ($this->refresh_version) {
-        $value = c_database_string::REFRESH_VERSION;
+        $value .= c_database_string::REFRESH_VERSION;
       }
     }
     else if (is_string($this->rename_to)) {
-      $value = $this->p_do_build_rename_to();
+      $value .= $this->p_do_build_rename_to();
     }
     else if (is_string($this->owner_to)) {
-      $value = $this->p_do_build_owner_to();
+      $value .= $this->p_do_build_owner_to();
     }
     else if (is_string($this->set_schema)) {
-      $value = $this->p_do_build_set_schema();
+      $value .= $this->p_do_build_set_schema();
     }
     else {
       unset($value);
@@ -154,7 +154,6 @@ class c_database_alter_coalation extends c_database_query {
     }
 
     $this->value = static::p_QUERY_COMMAND;
-    $this->value .= ' ' . $this->name;
     $this->value .= ' ' . $value;
     unset($value);
 
diff --git a/common/database/classes/database_alter_conversion.php b/common/database/classes/database_alter_conversion.php
index 1cb406e..f8fbfb1 100644
--- a/common/database/classes/database_alter_conversion.php
+++ b/common/database/classes/database_alter_conversion.php
@@ -83,15 +83,15 @@ class c_database_alter_conversion extends c_database_query {
       return new c_base_return_false();
     }
 
-    $value = NULL;
+    $value = $this->p_do_build_name() . ' ';
     if (is_string($this->rename_to)) {
-      $value = $this->p_do_build_rename_to();
+      $value .= $this->p_do_build_rename_to();
     }
     else if (is_string($this->owner_to)) {
-      $value = $this->p_do_build_owner_to();
+      $value .= $this->p_do_build_owner_to();
     }
     else if (is_string($this->set_schema)) {
-      $value = $this->p_do_build_set_schema();
+      $value .= $this->p_do_build_set_schema();
     }
     else {
       unset($value);
@@ -99,7 +99,6 @@ class c_database_alter_conversion extends c_database_query {
     }
 
     $this->value = static::p_QUERY_COMMAND;
-    $this->value .= ' ' . $this->name;
     $this->value .= ' ' . $value;
     unset($value);
 
diff --git a/common/database/classes/database_alter_database.php b/common/database/classes/database_alter_database.php
index a3f85d6..a19f4a0 100644
--- a/common/database/classes/database_alter_database.php
+++ b/common/database/classes/database_alter_database.php
@@ -147,25 +147,27 @@ class c_database_alter_database extends c_database_query {
       return new c_base_return_false();
     }
 
-    $value = NULL;
+    $value = $this->p_do_build_name() . ' ';
     if ($this->option instanceof c_database_argument_database_option) {
-      $this->option->do_build_argument();
-      $value = $this->option->get_value_exact();
+      // @todo: review this, the code may and probably should be converted into a trait.
+      if ($this->option->do_build_argument() instanceof c_base_return_true) {
+        $value .= $this->option->get_value_exact();
+      }
     }
     else if (is_string($this->rename_to)) {
-      $value = $this->p_do_build_rename_to();
+      $value .= $this->p_do_build_rename_to();
     }
     else if (is_string($this->owner_to)) {
-      $value = $this->p_do_build_owner_to();
+      $value .= $this->p_do_build_owner_to();
     }
     else if (is_string($this->set_tablespace)) {
-      $value = $this->p_do_build_set_tablespace();
+      $value .= $this->p_do_build_set_tablespace();
     }
     else if (is_array($this->set)) {
-      $value = $this->p_do_build_set();
+      $value .= $this->p_do_build_set();
     }
     else if (is_array($this->reset)) {
-      $value = $this->p_do_build_reset();
+      $value .= $this->p_do_build_reset();
     }
     else {
       unset($value);
@@ -173,7 +175,6 @@ class c_database_alter_database extends c_database_query {
     }
 
     $this->value = static::p_QUERY_COMMAND;
-    $this->value .= ' ' . $this->name;
     $this->value .= ' ' . $value;
     unset($value);
 
diff --git a/common/database/classes/database_alter_default_privileges.php b/common/database/classes/database_alter_default_privileges.php
index f170be5..478e75a 100644
--- a/common/database/classes/database_alter_default_privileges.php
+++ b/common/database/classes/database_alter_default_privileges.php
@@ -8,20 +8,22 @@ namespace n_koopa;
 require_once('common/base/classes/base_error.php');
 require_once('common/base/classes/base_return.php');
 
-require_once('common/database/enumerations/database_action.php');
 require_once('common/database/enumerations/database_cascade.php');
-require_once('common/database/enumerations/database_on.php');
 require_once('common/database/enumerations/database_privilege.php');
 
 require_once('common/database/classes/database_query.php');
 
 require_once('common/database/enumerations/database_cascade.php');
+require_once('common/database/enumerations/database_grant.php');
 
-require_once('common/database/traits/database_action.php');
 require_once('common/database/traits/database_cascade.php');
 require_once('common/database/traits/database_for_role.php');
+require_once('common/database/traits/database_grant.php');
 require_once('common/database/traits/database_grant_option_for.php');
 require_once('common/database/traits/database_in_schema.php');
+require_once('common/database/traits/database_on.php');
+require_once('common/database/traits/database_privilege.php');
+require_once('common/database/traits/database_to_role.php');
 require_once('common/database/traits/database_with_grant_option.php');
 
 /**
@@ -30,37 +32,33 @@ require_once('common/database/traits/database_with_grant_option.php');
  * @see: https://www.postgresql.org/docs/current/static/sql-alterdefaultpriveleges.html
  */
 class c_database_alter_default_priveleges extends c_database_query {
-  use t_database_action;
   use t_database_cascade;
   use t_database_for_role;
+  use t_database_grant;
   use t_database_grant_option_for;
   use t_database_in_schema;
+  use t_database_on;
+  use t_database_privilege;
+  use t_database_to_role;
   use t_database_with_grant_option;
 
   protected const p_QUERY_COMMAND = 'alter default privileges';
 
-  protected $abbreviated;
-  protected $on;
-  protected $privileges;
-  protected $role_names;
-
   /**
    * Class constructor.
    */
   public function __construct() {
     parent::__construct();
 
-    $this->action            = NULL;
     $this->cascade           = NULL;
     $this->for_role          = NULL;
+    $this->grant             = NULL;
     $this->grant_option_for  = NULL;
     $this->in_schema         = NULL;
+    $this->on                = NULL;
+    $this->privilege         = NULL;
+    $this->to_role           = NULL;
     $this->with_grant_option = NULL;
-
-    $this->abbreviated = NULL;
-    $this->on          = NULL;
-    $this->privileges  = NULL;
-    $this->role_names  = NULL;
   }
 
   /**
@@ -69,17 +67,15 @@ class c_database_alter_default_priveleges extends c_database_query {
   public function __destruct() {
     parent::__destruct();
 
-    unset($this->action);
     unset($this->cascade);
     unset($this->for_role);
+    unset($this->grant);
     unset($this->grant_option_for);
     unset($this->in_schema);
-    unset($this->with_grant_option);
-
-    unset($this->abbreviated);
     unset($this->on);
-    unset($this->privileges);
-    unset($this->role_names);
+    unset($this->privilege);
+    unset($this->to_role);
+    unset($this->with_grant_option);
   }
 
   /**
@@ -104,323 +100,64 @@ class c_database_alter_default_priveleges extends c_database_query {
   }
 
   /**
-   * Assigns the SQL ON operation.
-   *
-   * @param int|null $on
-   *   Whether or not to use the ON operation in the query.
-   *   Set to NULL to disable.
-   *
-   * @return c_base_return_status
-   *   TRUE on success, FALSE otherwise.
-   *   FALSE with error bit set is returned on error.
-   */
-  public function set_on($on) {
-    if (is_null($on)) {
-      $this->on = NULL;
-      return new c_base_return_true();
-    }
-
-    switch ($on) {
-      case e_database_on::TABLES_TO:
-      case e_database_on::SEQUENCES:
-      case e_database_on::FUNCTIONS:
-      case e_database_on::TYPES:
-      case e_database_on::SCHEMAS:
-        $this->on = $on;
-        return new c_base_return_true();
-      default:
-        break;
-    }
-
-    $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'on', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
-    return c_base_return_error::s_false($error);
-  }
-
-  /**
-   * Assigns the SQL privileges.
-   *
-   * @param int|null $privilege
-   *   Whether or not to use the ON operation in the query.
-   *   Set to NULL to disable.
-   *   When NULL, this will remove all values.
-   *
-   * @return c_base_return_status
-   *   TRUE on success, FALSE otherwise.
-   *   FALSE with error bit set is returned on error.
-   */
-  public function set_privilege($privilege) {
-    if (is_null($privilege)) {
-      $this->privileges = NULL;
-      return new c_base_return_true();
-    }
-
-    if (is_int($privilege)) {
-      if (!is_array($this->privilege)) {
-        $this->privileges = [];
-      }
-
-      $this->privileges[] = $privilege;
-      return new c_base_return_true();
-    }
-
-    $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'privilege', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
-    return c_base_return_error::s_false($error);
-  }
-
-  /**
-   * Set the role names.
-   *
-   * @param c_database_argument_role_name|null $role_name
-   *   The role name to use.
-   *   Set to NULL to disable.
-   *   When NULL, this will remove all values.
-   *
-   * @return c_base_return_status
-   *   TRUE on success, FALSE otherwise.
-   *   FALSE with error bit set is returned on error.
-   */
-  public function set_role_name($role_name) {
-    if (is_null($role_name)) {
-      $this->role_names = NULL;
-      return new c_base_return_true();
-    }
-
-    if ($role_name instanceof c_database_argument_role_name) {
-      if (!is_array($this->role_names)) {
-        $this->role_names = [];
-      }
-
-      $this->role_names[] = $role_name;
-      return new c_base_return_true();
-    }
-
-    $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'role_name', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
-    return c_base_return_error::s_false($error);
-  }
-
-  /**
-   * Get the role names.
-   *
-   * @param int|null $index
-   *   (optional) Get the role name at the specified index.
-   *   When NULL, all role names are returned.
-   *
-   * @return c_database_argument_role_name|c_base_return_array|c_base_return_null
-   *   An array of role names or NULL if not defined.
-   *   A single role name is returned if $index is an integer.
-   *   NULL with the error bit set is returned on error.
-   */
-  public function get_role_name($index = NULL) {
-    if (is_null($this->role_names)) {
-      return new c_base_return_null();
-    }
-
-    if (is_null($index)) {
-      if (is_array($this->role_names)) {
-        return c_base_return_array::s_new($this->role_names);
-      }
-    }
-    else {
-      if (is_int($index) && array_key_exists($index, $this->role_names) && $this->role_names[$index] instanceof c_database_argument_role_name) {
-        return $this->role_names[$index];
-      }
-
-      $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'role_names[index]', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
-      return c_base_return_error::s_null($error);
-    }
-
-    $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'role_names', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
-    return c_base_return_error::s_null($error);
-  }
-
-  /**
-   * Get the ON operation status.
-   *
-   * @return c_base_return_int|c_base_return_null
-   *   Integer representing the on operation is returned on success.
-   *   NULL is returned if undefined.
-   *   FALSE with error bit set is returned on error.
-   */
-  protected function get_on() {
-    if (is_null($this->on)) {
-      return new c_base_return_null();
-    }
-
-    return c_base_return_int::s_new($this->on);
-  }
-
-  /**
-   * Get the privileges.
-   *
-   * @param int|null $index
-   *   (optional) Get the privilege at the specified index.
-   *   When NULL, all privileges are returned.
-   *
-   * @return int|c_base_return_array|c_base_return_null
-   *   An array of privileges or NULL if not defined.
-   *   A single privilege is returned if $index is an integer.
-   *   NULL with the error bit set is returned on error.
-   */
-  public function get_privilege($index = NULL) {
-    if (is_null($this->privileges)) {
-      return new c_base_return_null();
-    }
-
-    if (is_null($index)) {
-      if (is_array($this->privileges)) {
-        return c_base_return_array::s_new($this->privileges);
-      }
-    }
-    else {
-      if (is_int($index) && array_key_exists($index, $this->privileges) && $this->privileges[$index] instanceof c_database_argument_aggregate_signature) {
-        return clone($this->privileges[$index]);
-      }
-
-      $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'privileges[index]', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
-      return c_base_return_error::s_null($error);
-    }
-
-    $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'privileges', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
-    return c_base_return_error::s_null($error);
-  }
-
-  /**
    * Implements do_build().
    */
   public function do_build() {
-    if (is_null($this->grant) || !(is_array($this->role_names) && !empty($this->role_names))) {
+    if (is_null($this->grant) || !(is_array($this->to_role) && !empty($this->to_role))) {
       return new c_base_return_false();
     }
 
-    switch ($this->action) {
-        case e_database_action::_GRANT:
-        case e_database_action::_REVOKE:
-          break;
-        default:
-          return new c_base_return_false();
-    }
-
     $value = NULL;
     if ($this->for_role) {
       $value .= $this->p_do_build_for_role();
     }
 
-    // [ IN SCHEMA schema_name [, ... ] ]
     if (is_array($this->in_schema) && !empty($this->in_schema)) {
       $value .= is_null($value) ? '' : ' ';
       $value .= $this->p_do_build_in_schema();
     }
 
-    if ($this->action === e_database_action::ACTION_GRANT) {
+    if (is_int($this->grant)) {
       $value .= is_null($value) ? '' : ' ';
-      $value .= c_database_string::GRANT;
-    }
-    else if ($this->action === e_database_action::ACTION_REVOKE) {
-      $value .= is_null($value) ? '' : ' ';
-      $value .= c_database_string::REVOKE;
+      $value .= $this->p_do_build_grant();
 
-      if ($this->grant_option_for) {
-        $value .= ' ' . $this->p_do_build_grant_option_for();
-      }
-    }
-
-    // [ { SELECT | INSERT | UPDATE | DELETE | TRUNCATE | REFERENCES | TRIGGER | USAGE | EXECUTE | CREATE } [, ...] | ALL ]
-    $privileges = '';
-    foreach ($this->privileges as $privilege) {
-      $privileges .= ', ';
-      switch ($privilege) {
-        case e_database_privilege::SELECT:
-          $privileges .= c_database_string::SELECT;
-          break;
-        case e_database_privilege::INSERT:
-          $privileges .= c_database_string::INSERT;
-          break;
-        case e_database_privilege::UPDATE:
-          $privileges .= c_database_string::UPDATE;
-          break;
-        case e_database_privilege::DELETE:
-          $privileges .= c_database_string::DELETE;
-          break;
-        case e_database_privilege::TRUNCATE:
-          $privileges .= c_database_string::TRUNCATE;
-          break;
-        case e_database_privilege::REFERENCES:
-          $privileges .= c_database_string::REFERENCES;
-          break;
-        case e_database_privilege::TRIGGER:
-          $privileges .= c_database_string::TRIGGER;
-          break;
-        case e_database_privilege::USAGE:
-          $privileges .= c_database_string::USAGE;
-          break;
-        case e_database_privilege::EXECUTE:
-          $privileges .= c_database_string::EXECUTE;
-          break;
-        case e_database_privilege::CREATE:
-          $privileges .= c_database_string::CREATE;
-          break;
-        case e_database_privilege::ALL:
-          $privileges .= c_database_string::ALL;
-          break;
-        default:
-          break;
+      if ($this->grant === e_database_action::ACTION_REVOKE) {
+        if ($this->grant_option_for) {
+          $value .= ' ' . $this->p_do_build_grant_option_for();
+        }
       }
     }
 
     $value .= is_null($value) ? '' : ' ';
-    $value .= ltrim($privileges, ', ');
-    unset($privileges);
+    $value .= $this->p_do_build_privilege();
 
-    // ON ...
-    switch($this->on) {
-      case e_database_on::TABLES_TO:
-        $value .= ' ' . c_database_string::ON_TABLES_TO;
-        break;
-      case e_database_on::SEQUENCES:
-        $value .= ' ' . c_database_string::ON_SEQUENCES;
-        break;
-      case e_database_on::FUNCTIONS:
-        $value .= ' ' . c_database_string::ON_FUNCTIONS;
-        break;
-      case e_database_on::TYPES:
-        $value .= ' ' . c_database_string::ON_TYPES;
-        break;
-      case e_database_on::SCHEMAS:
-        $value .= ' ' . c_database_string::ON_SCHEMAS;
-        break;
+    if (is_int($this->on)) {
+      $value .= ' ' . $this->p_do_build_on();
     }
 
-    // [ TO | FROM ] ... role names ...
-    if ($this->action === e_database_action::GRANT) {
+    if ($this->grant === e_database_action::GRANT) {
       $value .= ' ' . c_database_string::TO;
     }
-    else if ($this->action === e_database_action::REVOKE) {
+    else if ($this->grant === e_database_action::REVOKE) {
       $value .= ' ' . c_database_string::FROM;
     }
 
-    foreach ($this->role_names as $role_name) {
-      if (!($role_name instanceof c_database_argument_role_name)) {
-        continue;
-      }
-
-      $role_name->do_build_argument();
-      $value .= ' ' . $role_name->get_value_exact();
+    if (is_array($this->to_role)) {
+      $value .= ' ' . $this->p_do_build_to_role();
     }
-    unset($role_name);
 
-    if ($this->action === e_database_action::GRANT) {
+    if ($this->grant === e_database_action::GRANT) {
       if ($this->with_grant_option) {
         $value .= ' ' . $this->p_do_build_with_grant_option();
       }
     }
-    else if ($this->action === e_database_action::REVOKE) {
+    else if ($this->grant === e_database_action::REVOKE) {
       if (is_int($this->cascade)) {
         $value .= ' ' . $this->p_do_build_cascade();
       }
     }
 
     $this->value = static::p_QUERY_COMMAND;
-    $this->value .= ' ' . $this->name;
     $this->value .= ' ' . $value;
     unset($value);
 
diff --git a/common/database/classes/database_alter_domain.php b/common/database/classes/database_alter_domain.php
index 0106a57..17e185a 100644
--- a/common/database/classes/database_alter_domain.php
+++ b/common/database/classes/database_alter_domain.php
@@ -48,7 +48,7 @@ class c_database_alter_coalation extends c_database_query {
     $this->name       = NULL;
     $this->owner_to   = NULL;
     $this->rename_to  = NULL;
-    $this->set_schema = NULL
+    $this->set_schema = NULL;
 
     $this->expression = NULL;
     $this->constraint = NULL;
@@ -239,124 +239,123 @@ class c_database_alter_coalation extends c_database_query {
       return new c_base_return_false();
     }
 
-    $action = NULL;
+    $value = $this->p_do_build_name() . ' ';
     switch ($this->action) {
         case e_database_action::ADD:
           if (!is_array($this->constraint)) {
-            unset($action);
+            unset($value);
             return new c_base_return_false();
           }
 
-          $action = c_database_string::ADD;
-          $action .= ' ' . $this->constraint['name'];
+          $value .= c_database_string::ADD;
+          $value .= ' ' . $this->constraint['name'];
 
           if ($this->property === e_database_property::NOT_VALID) {
-            $action .= ' ' . c_database_string::NOT_VALID;
+            $value .= ' ' . c_database_string::NOT_VALID;
           }
           break;
 
         case e_database_action::DROP:
-          $action = c_database_string::DROP;
+          $value .= c_database_string::DROP;
           if ($this->property === e_database_property::NOT_NULL) {
-            $action .= ' ' . c_database_string::NOT_NULL;
+            $value .= ' ' . c_database_string::NOT_NULL;
           }
           break;
 
         case e_database_action::DROP_CONSTRAINT:
           if (!is_array($this->constraint['name'])) {
-            unset($action);
+            unset($value);
             return new c_base_return_false();
           }
 
-          $action = c_database_string::DROP_CONSTRAINT;
+          $value .= c_database_string::DROP_CONSTRAINT;
           if ($this->property === e_database_property::IF_EXISTS) {
-            $action .= ' ' . c_database_string::IF_EXISTS;
+            $value .= ' ' . c_database_string::IF_EXISTS;
           }
 
-          $action .= ' ' . $this->constraint['name'];
+          $value .= ' ' . $this->constraint['name'];
 
           if ($this->constraint['cascade'] === e_database_cascade::CASCADE) {
-            $action .= ' ' . c_database_string::CASCADE;
+            $value .= ' ' . c_database_string::CASCADE;
           }
           else if ($this->constraint['cascade'] === e_database_cascade::RESTRICT) {
-            $action .= ' ' . c_database_string::RESTRICT;
+            $value .= ' ' . c_database_string::RESTRICT;
           }
           break;
 
         case e_database_action::DROP_DEFAULT:
-          $action = c_database_string::DROP_DEFAULT;
+          $value .= c_database_string::DROP_DEFAULT;
           break;
 
         case e_database_action::OWNER_TO:
           if (!is_string($this->owner_to)) {
-            unset($action);
+            unset($value);
             return new c_base_return_false();
           }
 
-          $action = $this->p_do_build_owner_to();
+          $value .= $this->p_do_build_owner_to();
           break;
 
         case e_database_action::RENAME_CONSTRAINT:
           if (!is_string($this->constraint['name']) || !is_string($this->constraint['name_new'])) {
-            unset($action);
+            unset($value);
             return new c_base_return_false();
           }
 
-          $action = c_database_string::RENAME_CONSTRAINT . ' ' . $this->constraint['name'] . ' ' . c_database_string::TO . ' ' . $this->constraint['name_new'];
+          $value .= c_database_string::RENAME_CONSTRAINT . ' ' . $this->constraint['name'] . ' ' . c_database_string::TO . ' ' . $this->constraint['name_new'];
           break;
 
         case e_database_action::RENAME_TO:
           if (!is_string($this->rename_to)) {
-            unset($action);
+            unset($value);
             return new c_base_return_false();
           }
 
-          $action = $this->p_do_build_rename_to();
+          $value .= $this->p_do_build_rename_to();
           break;
 
         case e_database_action::SET:
-          $action = c_database_string::SET;
+          $value = c_database_string::SET;
           if ($this->property === e_database_property::NOT_NULL) {
-            $action .= ' ' . c_database_string::NOT_NULL;
+            $value .= ' ' . c_database_string::NOT_NULL;
           }
           break;
 
         case e_database_action::SET_DEFAULT:
           if (!is_string($this->expression)) {
-            unset($action);
+            unset($value);
             return new c_base_return_false();
           }
 
-          $action = c_database_string::SET_DEFAULT . ' ' . $this->expression;
+          $value .= c_database_string::SET_DEFAULT . ' ' . $this->expression;
           break;
 
         case e_database_action::SET_SCHEMA:
           if (!is_string($this->set_schema)) {
-            unset($action);
+            unset($value);
             return new c_base_return_false();
           }
 
-          $action = $this->p_do_build_set_schema();
+          $value .= $this->p_do_build_set_schema();
           break;
 
         case e_database_action::VALIDATE_CONSTRAINT:
           if (!is_array($this->constraint)) {
-            unset($action);
+            unset($value);
             return new c_base_return_false();
           }
 
-          $action = c_database_string::VALIDATE_CONSTRAINT . ' ' . $this->constraint['name'];
+          $value .= c_database_string::VALIDATE_CONSTRAINT . ' ' . $this->constraint['name'];
           break;
 
         default:
-          unset($action);
+          unset($value);
           return new c_base_return_false();
     }
 
     $this->value = static::p_QUERY_COMMAND;
-    $this->value .= ' ' . $this->name;
-    $this->value .= ' ' . $action;
-    unset($action);
+    $this->value .= ' ' . $value;
+    unset($value);
 
     return new c_base_return_true();
   }
diff --git a/common/database/classes/database_alter_event_trigger.php b/common/database/classes/database_alter_event_trigger.php
index 9f5394a..deb861c 100644
--- a/common/database/classes/database_alter_event_trigger.php
+++ b/common/database/classes/database_alter_event_trigger.php
@@ -87,50 +87,50 @@ class c_database_alter_coalation extends c_database_query {
       return new c_base_return_false();
     }
 
-    $action = NULL;
+    $value = $this->p_do_build_name() . ' ';
     switch($this->action) {
       case e_database_action::DISABLE:
-        $this->action = c_database_string::DISABLE;
+        $value .= c_database_string::DISABLE;
         break;
       case e_database_action::ENABLE:
-        $action = c_database_string::ENABLE;
+        $value .= c_database_string::ENABLE;
         if ($this->action_property === e_database_property::REPLICA) {
-          $action .= ' ' . c_database_string::REPLICA;
+          $value .= ' ' . c_database_string::REPLICA;
         }
         else if ($this->action_property === e_database_property::ALWAYS) {
-          $action .= ' ' . c_database_string::ALWAYS;
+          $value .= ' ' . c_database_string::ALWAYS;
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_action::OWNER_TO:
         if (is_string($this->owner_to)) {
-          $action = $this->p_do_build_owner_to();
+          $value .= $this->p_do_build_owner_to();
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_action::RENAME_TO:
         if (is_string($this->rename_to)) {
-          $action = $this->p_do_build_rename_to();
+          $value .= $this->p_do_build_rename_to();
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       default:
-        unset($action);
+        unset($value);
         return new c_base_return_false();
     }
 
     $this->value = static::p_QUERY_COMMAND;
-    $this->value .= ' ' . $action;
-    unset($action);
+    $this->value .= ' ' . $value;
+    unset($value);
 
     return new c_base_return_true();
   }
diff --git a/common/database/classes/database_alter_extension.php b/common/database/classes/database_alter_extension.php
index 3046ced..03f00bf 100644
--- a/common/database/classes/database_alter_extension.php
+++ b/common/database/classes/database_alter_extension.php
@@ -85,60 +85,60 @@ class c_database_alter_extension extends c_database_query {
       return new c_base_return_false();
     }
 
-    $action = $this->name . ' ';
+    $value = $this->p_do_build_name() . ' ';
     switch($this->action) {
       case e_database_action::UPDATE:
-        $action .= c_database_string::UPDATE;
+        $value .= c_database_string::UPDATE;
         if (is_string($this->action_parameter)) {
-          $action .= ' ' . c_database_string::TO . ' ' . $this->action_parameter;
+          $value .= ' ' . c_database_string::TO . ' ' . $this->action_parameter;
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_action::SET_SCHEMA:
         if (is_string($this->set_schema)) {
-          $action = $this->p_do_build_set_schema();
+          $value = $this->p_do_build_set_schema();
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_action::ADD:
-        $action .= c_database_string::ADD;
+        $value .= c_database_string::ADD;
         if ($this->action_parameter instanceof c_database_member_object && $this->action_parameter->do_build() instanceof c_base_return_true) {
-          $action .= ' ' . $this->action_parameter->get_value();
+          $value .= ' ' . $this->action_parameter->get_value();
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_action::DROP:
-        $action .= c_database_string::DROP;
+        $value .= c_database_string::DROP;
         if ($this->action_parameter instanceof c_database_member_object) {
           if ($this->action_parameter->do_build() instanceof c_base_return_true) {
-            $action .= ' ' . $this->action_parameter->get_value();
+            $value .= ' ' . $this->action_parameter->get_value();
           }
           else {
-            unset($action);
+            unset($value);
             return new c_base_return_false();
           }
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       default:
-        unset($action);
+        unset($value);
         return new c_base_return_false();
     }
-    unset($action);
+    unset($value);
 
-    $this->value = $action;
+    $this->value = $value;
     return new c_base_return_true();
   }
 }
diff --git a/common/database/classes/database_alter_foreign_data_wrapper.php b/common/database/classes/database_alter_foreign_data_wrapper.php
index a9cd2ce..8376662 100644
--- a/common/database/classes/database_alter_foreign_data_wrapper.php
+++ b/common/database/classes/database_alter_foreign_data_wrapper.php
@@ -126,7 +126,7 @@ class c_database_alter_foreign_data_wrapper extends c_database_query {
     }
 
     $this->value = static::p_QUERY_COMMAND;
-    $this->value .= ' ' . $this->name;
+    $this->value .= ' ' . $this->p_do_build_name();
     $this->value .= ' ' . $action;
     unset($action);
 
diff --git a/common/database/classes/database_alter_foreign_table.php b/common/database/classes/database_alter_foreign_table.php
index 052c001..5deb5a9 100644
--- a/common/database/classes/database_alter_foreign_table.php
+++ b/common/database/classes/database_alter_foreign_table.php
@@ -353,7 +353,7 @@ class c_database_alter_foreign_table extends c_database_query {
     }
 
     $this->value = static::p_QUERY_COMMAND;
-    $this->value .= ' ' . $this->name;
+    $this->value .= ' ' . $this->p_do_build_name();
 
     if ($this->include_descendents) {
       $this->value .' *';
diff --git a/common/database/classes/database_alter_function.php b/common/database/classes/database_alter_function.php
index bc3389e..53a9c39 100644
--- a/common/database/classes/database_alter_function.php
+++ b/common/database/classes/database_alter_function.php
@@ -1,7 +1,7 @@
 <?php
 /**
  * @file
- * Provides a class for specific Postgesql query: ALTER COALATION.
+ * Provides a class for specific Postgesql query: ALTER FUNCTION.
  */
 namespace n_koopa;
 
@@ -10,6 +10,14 @@ require_once('common/base/classes/base_return.php');
 
 require_once('common/database/classes/database_query.php');
 
+require_once('common/database/traits/database_argument_type.php');
+require_once('common/database/traits/database_depends_on_extension.php');
+require_once('common/database/traits/database_function_action.php');
+require_once('common/database/traits/database_name.php');
+require_once('common/database/traits/database_owner_to.php');
+require_once('common/database/traits/database_rename_to.php');
+require_once('common/database/traits/database_restrict.php');
+require_once('common/database/traits/database_set_schema.php');
 
 /**
  * The class for building and returning a Postgresql ALTER COALATION query string.
@@ -19,20 +27,46 @@ require_once('common/database/classes/database_query.php');
  * @see: https://www.postgresql.org/docs/current/static/sql-alteraggregate.html
  */
 class c_database_alter_coalation extends c_database_query {
-  protected const p_QUERY_COMMAND = 'alter coalation';
+  use t_database_argument_type;
+  use t_database_depends_on_extension;
+  use t_database_function_action;
+  use t_database_name;
+  use t_database_owner_to;
+  use t_database_rename_to;
+  use t_database_restrict;
+  use t_database_set_schema;
 
+  protected const p_QUERY_COMMAND = 'alter function';
 
   /**
    * Class constructor.
    */
   public function __construct() {
     parent::__construct();
+
+    $this->argument_type        = NULL;
+    $this->depends_on_extension = NULL;
+    $this->function_action      = NULL;
+    $this->name                 = NULL;
+    $this->owner_to             = NULL;
+    $this->rename_to            = NULL;
+    $this->restrict             = NULL;
+    $this->set_schema           = NULL;
   }
 
   /**
    * Class destructor.
    */
   public function __destruct() {
+    unset($this->argument_type);
+    unset($this->depends_on_extension);
+    unset($this->function_action);
+    unset($this->name);
+    unset($this->owner_to);
+    unset($this->rename_to);
+    unset($this->restrict);
+    unset($this->set_schema);
+
     parent::__destruct();
   }
 
@@ -61,9 +95,43 @@ class c_database_alter_coalation extends c_database_query {
    * Implements do_build().
    */
   public function do_build() {
-    $this->value = NULL;
+    if (!is_string($this->name)) {
+      return new c_base_return_false();
+    }
+
+    $value = $this->p_do_build_name();
+
+    if (is_array($this->argument_type) && !empty($this->argument_type)) {
+      $value .= ' ' . $this->p_do_build_argument_type();
+    }
+
+    if (is_array($this->function_action)) {
+      $value .= ' ' . $this->p_do_build_function_action();
+
+      if ($this->restrict) {
+        $value .= ' ' . $this->p_do_build_restrict();
+      }
+    }
+    else if (is_string($this->rename_to)) {
+      $value .= $this->p_do_build_rename_to();
+    }
+    else if (is_string($this->owner_to)) {
+      $value .= $this->p_do_build_owner_to();
+    }
+    else if (is_string($this->set_schema)) {
+      $value .= $this->p_do_build_set_schema();
+    }
+    else if (is_string($this->depends_on_extension)) {
+      $value .= $this->p_do_build_depends_on_extension();
+    }
+    else {
+      unset($value);
+      return new c_base_return_false();
+    }
 
-    // @todo
+    $this->value = static::p_QUERY_COMMAND;
+    $this->value .= ' ' . $value;
+    unset($value);
 
     return new c_base_return_true();
   }
diff --git a/common/database/classes/database_member_object.php b/common/database/classes/database_member_object.php
index 00220c2..f8c445a 100644
--- a/common/database/classes/database_member_object.php
+++ b/common/database/classes/database_member_object.php
@@ -79,150 +79,150 @@ class c_database_member_object extends c_database_query {
       return new c_base_return_false();
     }
 
-    $action = NULL;
+    $value = NULL;
     switch($this->action) {
       case e_database_method_object::ACCESS_METHOD:
-        $action = c_database_string::ACCESS_METHOD . ' ' . $this->name;
+        $value = c_database_string::ACCESS_METHOD . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::AGGREGATE:
-        $action = c_database_string::AGGREGATE . ' ' . $this->name;
+        $value = c_database_string::AGGREGATE . ' ' . $this->p_do_build_name();
         // TODO: as a query argument?
         if ($this->action_parameter instanceof c_database_alter_aggregate && $this->action_parameter->do_build()) {
-          $action .= ' ( ' . $this->action_parameter->get_value() . ' )';
+          $value .= ' ( ' . $this->action_parameter->get_value() . ' )';
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_method_object::CAST:
         // uses 'name' property to represent AS 'source_type'
-        $action = c_database_string::CAST;
+        $value = c_database_string::CAST;
         if (is_string($this->action_parameter)) {
-          $action .= ' ' . $this->name . ' ' . c_database_string::AS . ' ( ' . $this->action_parameter . ' )';
+          $value .= ' ' . $this->p_do_build_name() . ' ' . c_database_string::AS . ' ( ' . $this->action_parameter . ' )';
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_method_object::COLLATION:
-        $action = c_database_string::COLLATION . ' ' . $this->name;
+        $value = c_database_string::COLLATION . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::CONVERSION:
-        $action = c_database_string::CONVERSION . ' ' . $this->name;
+        $value = c_database_string::CONVERSION . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::DOMAIN:
-        $action = c_database_string::DOMAIN . ' ' . $this->name;
+        $value = c_database_string::DOMAIN . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::EVENT_TRIGGER:
-        $action = c_database_string::EVENT_TRIGGER . ' ' . $this->name;
+        $value = c_database_string::EVENT_TRIGGER . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::FOREIGN_DATA_WRAPPER:
-        $action = c_database_string::FOREIGN_DATA_WRAPPER . ' ' . $this->name;
+        $value = c_database_string::FOREIGN_DATA_WRAPPER . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::FOREIGN_TABLE:
-        $action = c_database_string::FOREIGN_TABLE . ' ' . $this->name;
+        $value = c_database_string::FOREIGN_TABLE . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::FUNCTION:
-        $action = c_database_string::FUNCTION . ' ' . $this->name;
+        $value = c_database_string::FUNCTION . ' ' . $this->p_do_build_name();
         // TODO: finish adding support for function
         // TODO: as a query argument?
         /*if ($this->action_parameter instanceof c_database_function && $this->action_parameter->do_build()) {
-          $action .= ' ( ' . $this->action_parameter->get_value() . ' )';
+          $value .= ' ( ' . $this->action_parameter->get_value() . ' )';
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }*/
         break;
       case e_database_method_object::MATERIALIZED_VIEW:
-        $action = c_database_string::MATERIALIZED_VIEW . ' ' . $this->name;
+        $value = c_database_string::MATERIALIZED_VIEW . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::OPERATOR:
-        $action = c_database_string::OPERATOR . ' ' . $this->name;
+        $value = c_database_string::OPERATOR . ' ' . $this->p_do_build_name();
         if (isset($this->action_parameter[0]) && is_string($this->action_parameter[0]) && isset($this->action_parameter[1]) && is_string($this->action_parameter[1])) {
-          $action .= ' ' . $this->action_parameter[0] . ' ( ' . $this->action_parameter[0] . ', ' . $this->action_parameter[1] . ' )';
+          $value .= ' ' . $this->action_parameter[0] . ' ( ' . $this->action_parameter[0] . ', ' . $this->action_parameter[1] . ' )';
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_method_object::OPERATOR_CLASS:
-        $action = c_database_string::OPERATOR_CLASS . ' ' . $this->name;
+        $value = c_database_string::OPERATOR_CLASS . ' ' . $this->p_do_build_name();
         if (is_string($this->action_parameter)) {
-          $action .= ' ' . c_database_string::USING . ' ' . $this->action_parameter;
+          $value .= ' ' . c_database_string::USING . ' ' . $this->action_parameter;
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_method_object::OPERATOR_FAMILY:
-        $action = c_database_string::OPERATOR_FAMILY . ' ' . $this->name;
+        $value = c_database_string::OPERATOR_FAMILY . ' ' . $this->p_do_build_name();
         if (is_string($this->action_parameter)) {
-          $action .= ' ' . c_database_string::USING . ' ' . $this->action_parameter;
+          $value .= ' ' . c_database_string::USING . ' ' . $this->action_parameter;
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_method_object::LANGUAGE:
-        $action = c_database_string::LANGUAGE . ' ' . $this->name;
+        $value = c_database_string::LANGUAGE . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::PROCEDURAL:
-        $action = c_database_string::PROCEDURAL . ' ' . c_database_string::LANGUAGE . ' ' . $this->name;
+        $value = c_database_string::PROCEDURAL . ' ' . c_database_string::LANGUAGE . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::SCHEMA:
-        $action = c_database_string::SCHEMA . ' ' . $this->name;
+        $value = c_database_string::SCHEMA . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::SEQUENCE:
-        $action = c_database_string::SEQUENCE . ' ' . $this->name;
+        $value = c_database_string::SEQUENCE . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::SERVER:
-        $action = c_database_string::SERVER . ' ' . $this->name;
+        $value = c_database_string::SERVER . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::TABLE:
-        $action = c_database_string::TABLE . ' ' . $this->name;
+        $value = c_database_string::TABLE . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::TEXT_SEARCH_CONFIGURATION:
-        $action = c_database_string::TEXT_SEARCH_CONFIGURATION . ' ' . $this->name;
+        $value = c_database_string::TEXT_SEARCH_CONFIGURATION . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::TEXT_SEARCH_DICTIONARY:
-        $action = c_database_string::TEXT_SEARCH_DICTIONARY . ' ' . $this->name;
+        $value = c_database_string::TEXT_SEARCH_DICTIONARY . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::TEXT_SEARCH_PARSER:
-        $action = c_database_string::TEXT_SEARCH_PARSER . ' ' . $this->name;
+        $value = c_database_string::TEXT_SEARCH_PARSER . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::TEXT_SEARCH_TEMPLATE:
-        $action = c_database_string::TEXT_SEARCH_TEMPLATE . ' ' . $this->name;
+        $value = c_database_string::TEXT_SEARCH_TEMPLATE . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::TRANSFORM_FOR:
-        $action = c_database_string::TRANSFORM_FOR . ' ' . $this->name;
+        $value = c_database_string::TRANSFORM_FOR . ' ' . $this->p_do_build_name();
         if (is_string($this->action_parameter)) {
-          $action .= ' ' . c_database_string::LANGUAGE . ' ' . $this->action_parameter;
+          $value .= ' ' . c_database_string::LANGUAGE . ' ' . $this->action_parameter;
         }
         else {
-          unset($action);
+          unset($value);
           return new c_base_return_false();
         }
         break;
       case e_database_method_object::TYPE:
-        $action = c_database_string::TYPE . ' ' . $this->name;
+        $value = c_database_string::TYPE . ' ' . $this->p_do_build_name();
         break;
       case e_database_method_object::VIEW:
-        $action = c_database_string::VIEW . ' ' . $this->name;
+        $value = c_database_string::VIEW . ' ' . $this->p_do_build_name();
         break;
       default:
-        unset($action);
+        unset($value);
         return new c_base_return_false();
     }
 
     $this->value = static::p_QUERY_COMMAND;
-    $this->value .= ' ' . $action;
-    unset($action);
+    $this->value .= ' ' . $value;
+    unset($value);
 
     return new c_base_return_true();
   }
diff --git a/common/database/classes/database_string.php b/common/database/classes/database_string.php
index a5b3d3b..ed43c99 100644
--- a/common/database/classes/database_string.php
+++ b/common/database/classes/database_string.php
@@ -25,6 +25,7 @@ class c_database_string {
   public const CONVERSION                 = 'conversion';
   public const CREATE                     = 'create';
   public const DELETE                     = 'delete';
+  public const DEPENDS_ON_EXTENSION       = 'depends on extension';
   public const DESCEND                    = 'desc';
   public const DISABLE_TRIGGER            = 'disable trigger';
   public const DOMAIN                     = 'domain';
@@ -50,6 +51,8 @@ class c_database_string {
   public const HANDLER                    = 'handler';
   public const IF_EXISTS                  = 'if exists';
   public const IN                         = 'in';
+  public const INOUT                      = 'inout';
+  public const IN_SCHEMA                  = 'in schema';
   public const INHERIT                    = 'inherit';
   public const INSERT                     = 'insert';
   public const IS_TEMPLATE                = 'is_template';
@@ -70,6 +73,7 @@ class c_database_string {
   public const OPERATOR_FAMILY            = 'operator family';
   public const OPTIONS                    = 'options';
   public const ORDER_BY                   = 'order by';
+  public const OUT                        = 'out';
   public const OWNER_TO                   = 'owner to';
   public const PROCEDURAL                 = 'procedural';
   public const PUBLIC                     = 'public';
diff --git a/common/database/enumerations/database_argument_mode.php b/common/database/enumerations/database_argument_mode.php
new file mode 100644
index 0000000..d193d96
--- /dev/null
+++ b/common/database/enumerations/database_argument_mode.php
@@ -0,0 +1,19 @@
+<?php
+/**
+ * @file
+ * Provides enumeration classes for managing codes used for generating specific Postgesql Queries.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+/**
+ * Codes associated with database argument type mode.
+ */
+class e_database_argument_mode {
+  public const NONE     = 0;
+  public const IN       = 1;
+  public const INOUT    = 2;
+  public const OUT      = 3;
+  public const VARIADIC = 4;
+}
diff --git a/common/database/enumerations/database_function_action.php b/common/database/enumerations/database_function_action.php
new file mode 100644
index 0000000..13aa27b
--- /dev/null
+++ b/common/database/enumerations/database_function_action.php
@@ -0,0 +1,33 @@
+<?php
+/**
+ * @file
+ * Provides enumeration classes for managing codes used for generating specific Postgesql Queries.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+/**
+ * Codes associated with postgresql function action information.
+ */
+class e_database_function_action {
+  public const NONE                       = 0;
+  public const CALLED_ON_NULL_INPUT       = 1;
+  public const IMMUTABLE                  = 2;
+  public const LEAKPROOF                  = 3;
+  public const NOT_LEAKPROOF              = 4;
+  public const PARALLEL_RESTRICTED        = 5;
+  public const PARALLEL_SAFE              = 6;
+  public const PARALLEL_UNSAFE            = 7;
+  public const RESET                      = 8;
+  public const RESET_ALL                  = 9;
+  public const RETURNS_NULL_ON_NULL_INPUT = 10;
+  public const SECURITY_DEFINER           = 11;
+  public const SECURITY_INVOKER           = 12;
+  public const SET_EQUAL                  = 13;
+  public const SET_FROM                   = 14;
+  public const SET_TO                     = 15;
+  public const STABLE                     = 16;
+  public const STRICT                     = 17;
+  public const VOLATILE                   = 18;
+}
diff --git a/common/database/enumerations/database_grant.php b/common/database/enumerations/database_grant.php
new file mode 100644
index 0000000..bcf00d8
--- /dev/null
+++ b/common/database/enumerations/database_grant.php
@@ -0,0 +1,17 @@
+<?php
+/**
+ * @file
+ * Provides enumeration classes for managing codes used for generating specific Postgesql Queries.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+/**
+ * Codes associated with database grant/revoke.
+ */
+class e_database_grant {
+  public const NONE   = 0;
+  public const GRANT  = 1;
+  public const REVOKE = 2;
+}
diff --git a/common/database/enumerations/database_role.php b/common/database/enumerations/database_role.php
new file mode 100644
index 0000000..9081400
--- /dev/null
+++ b/common/database/enumerations/database_role.php
@@ -0,0 +1,18 @@
+<?php
+/**
+ * @file
+ * Provides enumeration classes for managing codes used for generating specific Postgesql Queries.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+/**
+ * Codes associated with postgresql role information.
+ */
+class e_database_role {
+  public const NONE   = 0;
+  public const GROUP  = 1;
+  public const NAME   = 2;
+  public const PUBLIC = 3;
+}
diff --git a/common/database/traits/database_argument_type.php b/common/database/traits/database_argument_type.php
new file mode 100644
index 0000000..2db6c66
--- /dev/null
+++ b/common/database/traits/database_argument_type.php
@@ -0,0 +1,156 @@
+<?php
+/**
+ * @file
+ * Provides traits for specific Postgesql Queries.
+ *
+ * These traits are associated with argument_type.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+require_once('common/base/classes/base_error.php');
+require_once('common/base/classes/base_return.php');
+
+require_once('common/database/classes/database_string.php');
+
+require_once('common/database/enumerations/database_argument_mode.php');
+
+/**
+ * Provide the sql argument type functionality.
+ */
+trait t_database_argument_type {
+  protected $argument_type;
+
+  /**
+   * Set the argument type settings.
+   *
+   * @param string|null $argument_type
+   *   The argument type to assign.
+   *   Set to NULL to disable.
+   *   Setting to NULL removes all existing values.
+   * @param string|null $argument_name
+   *   When $argument_type is not NULL, this specifies the name of the argument.
+   * @param int|null $argument_mode
+   *   When $argument_type is not NULL, this specifies the argument mode code of the argument.
+   *
+   * @return c_base_return_status
+   *   TRUE on success, FALSE otherwise.
+   *   FALSE with the error bit set is returned on error.
+   */
+  public function set_argument_type($argument_type, $argument_name = NULL, $argument_mode = NULL) {
+    if (is_null($argument_type)) {
+      $this->argument_type = NULL;
+      return new c_base_return_true();
+    }
+
+    if (!is_string($argument_type)) {
+      $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'argument_type', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+      return c_base_return_error::s_false($error);
+    }
+
+    if (!is_string($argument_name)) {
+      $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'argument_name', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+      return c_base_return_error::s_false($error);
+    }
+
+    switch($argument_mode) {
+      case e_database_argument_mode::IN:
+      case e_database_argument_mode::INOUT:
+      case e_database_argument_mode::OUT:
+      case e_database_argument_mode::VARIADIC:
+        break;
+      default:
+        $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'argument_mode', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+        return c_base_return_error::s_false($error);
+    }
+
+    if (!is_array($this->argument_type)) {
+      $this->argument_type = [];
+    }
+
+    $this->argument_type[] = [
+      'type' => $argument_type,
+      'name' => $argument_name,
+      'mode' => $argument_mode,
+    ];
+
+    return new c_base_return_true();
+  }
+
+  /**
+   * Get the currently assigned sql argument type at the specified index.
+   *
+   * @param int|null $index
+   *   (optional) Get the argument type array at the specified index.
+   *   When NULL, all argument type are returned.
+   *
+   * @return c_base_return_array|c_base_return_null
+   *   A code representing the argument_type on success.
+   *   NULL is returned if not set (argument_type tablespace is not to be used).
+   *   NULL with the error bit set is returned on error.
+   */
+  public function get_argument_type($index = NULL) {
+    if (is_null($this->argument_type)) {
+      return new c_base_return_null();
+    }
+
+    if (is_null($this->argument_type['type'])) {
+      return c_base_return_array::s_new($this->argument_type);
+    }
+    else if (isset($this->argument_type[$index]) && is_array($this->argument_type[$index])) {
+      return c_base_return_int::s_new($this->argument_type[$index]);
+    }
+    else {
+      $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'argument_type', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+      return c_base_return_error::s_null($error);
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'argument_type', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
+    return c_base_return_error::s_null($error);
+  }
+
+  /**
+   * Perform the common build process for this trait.
+   *
+   * As an internal trait method, the caller is expected to perform any appropriate validation.
+   *
+   * @return string|null
+   *   A string is returned on success.
+   *   NULL is returned if there is nothing to process or there is an error.
+   */
+  protected function p_do_build_argument_type() {
+    if (is_null($this->argument_type)) {
+      return NULL;
+    }
+
+    $values = [];
+    foreach ($this->argument_type as $argument_type) {
+      $value = '';
+
+      switch($argument_type['mode']) {
+        case e_database_argument_mode::IN:
+          $value = c_database_string::IN;
+          break;
+        case e_database_argument_mode::INOUT:
+          $value = c_database_string::INOUT;
+          break;
+        case e_database_argument_mode::OUT:
+          $value = c_database_string::OUT;
+          break;
+        case e_database_argument_mode::VARIADIC:
+          $value = c_database_string::VARIADIC;
+          break;
+      }
+
+      $value .= ' ' . $argument_type['name'];
+      $value .= ' ' . $argument_type['type'];
+
+      $values[] = $value;
+    }
+    unset($argument_type);
+    unset($value);
+
+    return implode(', ', $values);
+  }
+}
diff --git a/common/database/traits/database_depends_on_extension.php b/common/database/traits/database_depends_on_extension.php
new file mode 100644
index 0000000..3f5141c
--- /dev/null
+++ b/common/database/traits/database_depends_on_extension.php
@@ -0,0 +1,81 @@
+<?php
+/**
+ * @file
+ * Provides traits for specific Postgesql Queries.
+ *
+ * These traits are associated with actions.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+require_once('common/base/classes/base_error.php');
+require_once('common/base/classes/base_return.php');
+
+require_once('common/database/classes/database_string.php');
+
+/**
+ * Provide the sql DEPENDS ON EXTENSION functionality.
+ */
+trait t_database_depends_on_extension {
+  protected $depends_on_extension;
+
+  /**
+   * Set the RENAME TO settings.
+   *
+   * @param string|null $depends_on_extension
+   *   The name to rename to.
+   *   Set to NULL to disable.
+   *
+   * @return c_base_return_status
+   *   TRUE on success, FALSE otherwise.
+   *   FALSE with the error bit set is returned on error.
+   */
+  public function set_depends_on_extension($depends_on_extension) {
+    if (!is_null($depends_on_extension) && !is_string($depends_on_extension)) {
+      $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'depends_on_extension', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+      return c_base_return_error::s_false($error);
+    }
+
+    $this->depends_on_extension = $depends_on_extension;
+    return new c_base_return_true();
+  }
+
+  /**
+   * Get the currently assigned schema name to set to.
+   *
+   * @return c_base_return_string|c_base_return_null
+   *   An extension name on success.
+   *   NULL is returned if not set (depends on extension is not to be used).
+   *   NULL with the error bit set is returned on error.
+   */
+  public function get_depends_on_extension() {
+    if (is_null($this->depends_on_extension)) {
+      return new c_base_return_null();
+    }
+
+    if (is_string($this->depends_on_extension)) {
+      return c_base_return_string::s_new($this->depends_on_extension);
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'depends_on_extension', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
+    return c_base_return_error::s_null($error);
+  }
+
+  /**
+   * Perform the common build process for this trait.
+   *
+   * As an internal trait method, the caller is expected to perform any appropriate validation.
+   *
+   * @return string|null
+   *   A string is returned on success.
+   *   NULL is returned if there is nothing to process or there is an error.
+   */
+  protected function p_do_build_depends_on_extension() {
+    if (is_null($this->depends_on_extension)) {
+      return NULL;
+    }
+
+    return c_database_string::DEPENDS_ON_EXTENSION . ' ' . $this->depends_on_extension;
+  }
+}
diff --git a/common/database/traits/database_function_action.php b/common/database/traits/database_function_action.php
new file mode 100644
index 0000000..9c47935
--- /dev/null
+++ b/common/database/traits/database_function_action.php
@@ -0,0 +1,162 @@
+<?php
+/**
+ * @file
+ * Provides traits for specific Postgesql Queries.
+ *
+ * These traits are associated with function_action.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+require_once('common/base/classes/base_error.php');
+require_once('common/base/classes/base_return.php');
+
+require_once('common/database/classes/database_string.php');
+
+require_once('common/database/enumerations/database_argument_function_action.php');
+
+/**
+ * Provide the sql argument type functionality.
+ */
+trait t_database_function_action {
+  protected $function_action;
+
+  /**
+   * Set the argument type settings.
+   *
+   * @param int|null $function_action
+   *   The function action code to assign.
+   *   Set to NULL to disable.
+   *   Setting to NULL removes all existing values.
+   * @param string|int|null $parameter_1
+   *   Value for the first parameter if required by the $function_action_code.
+   *   A string representing the configuration parameter for SET_TO, SET_EQUAL, SET_FROM, or RESET.
+   *   An integer representing execution cost for COST.
+   *   An integer representing result rows for ROWS.
+   * @param string|null $parameter_2
+   *   Value for the second parameter if required by the $function_action_code.
+   *   SET_TO and SET_FROM use this as value, but if left as NULL then DEFAULT is used.
+   *
+   * @return c_base_return_status
+   *   TRUE on success, FALSE otherwise.
+   *   FALSE with the error bit set is returned on error.
+   */
+  public function set_function_action($function_action, $parameter_1 = NULL, $parameter_2 = NULL) {
+    if (is_null($function_action)) {
+      $this->function_action = NULL;
+      return new c_base_return_true();
+    }
+
+    switch($function_action) {
+      case e_database_function_action::CALLED_ON_NULL_INPUT:
+      case e_database_function_action::COST:
+      case e_database_function_action::IMMUTABLE:
+      case e_database_function_action::LEAKPROOF:
+      case e_database_function_action::NOT_LEAKPROOF:
+      case e_database_function_action::PARALLEL_RESTRICTED:
+      case e_database_function_action::PARALLEL_SAFE:
+      case e_database_function_action::PARALLEL_UNSAFE:
+      case e_database_function_action::RESET:
+      case e_database_function_action::RESET_ALL:
+      case e_database_function_action::RETURNS_NULL_ON_NULL_INPUT:
+      case e_database_function_action::ROWS:
+      case e_database_function_action::SECURITY_DEFINER:
+      case e_database_function_action::SECURITY_INVOKER:
+      case e_database_function_action::SET_EQUAL:
+      case e_database_function_action::SET_FROM:
+      case e_database_function_action::SET_TO:
+      case e_database_function_action::STABLE:
+      case e_database_function_action::STRICT:
+      case e_database_function_action::VOLATILE:
+        break;
+      default:
+        $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'function_action', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+        return c_base_return_error::s_false($error);
+    }
+
+    $action = [
+      'type' => $function_action,
+      'parameter_1' => NULL,
+      'parameter_2' => NULL,
+    ];
+
+    if ($function_action === e_database_function_action::COST || $function_action === e_database_function_action::ROWS) {
+      if (!is_int($parameter_1)) {
+        unset($action);
+        $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'parameter_1', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+        return c_base_return_error::s_false($error);
+      }
+
+      $action['parameter_1'] = $parameter_1;
+    }
+    else if ($function_action === e_database_function_action::SET_TO || $function_action === e_database_function_action::SET_EQUAL) {
+      if (!is_string($parameter_1)) {
+        unset($action);
+        $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'parameter_1', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+        return c_base_return_error::s_false($error);
+      }
+
+      if (!is_null($parameter_2) && !is_string($parameter_2)) {
+        unset($action);
+        $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'parameter_2', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+        return c_base_return_error::s_false($error);
+      }
+
+      $action['parameter_1'] = $parameter_1;
+      $action['parameter_2'] = $parameter_2;
+    }
+    else if ($function_action === e_database_function_action::SET_FROM || $function_action === e_database_function_action::RESET) {
+      if (!is_string($parameter_1)) {
+        unset($action);
+        $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'parameter_1', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+        return c_base_return_error::s_false($error);
+      }
+
+      $action['parameter_1'] = $parameter_1;
+    }
+
+    $this->function_action = $action;
+    unset($action);
+
+    return new c_base_return_true();
+  }
+
+  /**
+   * Get the currently assigned sql functionn action.
+   *
+   * @return c_base_return_array|c_base_return_null
+   *   An array representing the function action on success.
+   *   NULL is returned if not set (function action tablespace is not to be used).
+   *   NULL with the error bit set is returned on error.
+   */
+  public function get_function_action($index = NULL) {
+    if (is_null($this->function_action)) {
+      return new c_base_return_null();
+    }
+
+    if (is_array($this->function_action)) {
+      return c_base_return_array::s_new($this->function_action);
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'function_action', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
+    return c_base_return_error::s_null($error);
+  }
+
+  /**
+   * Perform the common build process for this trait.
+   *
+   * As an internal trait method, the caller is expected to perform any appropriate validation.
+   *
+   * @return string|null
+   *   A string is returned on success.
+   *   NULL is returned if there is nothing to process or there is an error.
+   */
+  protected function p_do_build_function_action() {
+    if (is_null($this->function_action)) {
+      return NULL;
+    }
+
+    // @todo
+  }
+}
diff --git a/common/database/traits/database_grant.php b/common/database/traits/database_grant.php
new file mode 100644
index 0000000..dfcc90e
--- /dev/null
+++ b/common/database/traits/database_grant.php
@@ -0,0 +1,93 @@
+<?php
+/**
+ * @file
+ * Provides traits for specific Postgesql Queries.
+ *
+ * These traits are associated with actions.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+require_once('common/base/classes/base_error.php');
+require_once('common/base/classes/base_return.php');
+
+require_once('common/database/classes/database_string.php');
+
+require_once('common/database/enumerations/database_grant.php');
+
+/**
+ * Provide the sql GRANT functionality.
+ * @fixme: doesn't group by support multiple arguments?
+ */
+trait t_database_grant {
+  protected $grant;
+
+  /**
+   * Set the GRANT settings.
+   *
+   * @param int|null $grant
+   *   The grant/revoke code to assign.
+   *   Set to NULL to disable.
+   *
+   * @return c_base_return_status
+   *   TRUE on success, FALSE otherwise.
+   *   FALSE with the error bit set is returned on error.
+   */
+  public function set_grant($grant) {
+    if (is_null($grant)) {
+      $this->grant = NULL;
+      return new c_base_return_true();
+    }
+
+    if ($grant === e_database_grant::GRANT || $grant === e_database_grant::REVOKE) {
+      $this->grant = $grant;
+      return new c_base_return_true();
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'grant', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+    return c_base_return_error::s_false($error);
+  }
+
+  /**
+   * Get the currently assigned grant code.
+   *
+   * @return c_base_return_int|c_base_return_null
+   *   A grant code on success.
+   *   NULL is returned if not set (grant is not to be used).
+   *   NULL with the error bit set is returned on error.
+   */
+  public function get_grant() {
+    if (is_null($this->grant)) {
+      return new c_base_return_null();
+    }
+
+    if (is_int($this->grant)) {
+      return c_base_return_int::s_new($this->grant);
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'grant', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
+    return c_base_return_error::s_null($error);
+  }
+
+  /**
+   * Perform the common build process for this trait.
+   *
+   * As an internal trait method, the caller is expected to perform any appropriate validation.
+   *
+   * @return string|null
+   *   A string is returned on success.
+   *   NULL is returned if there is nothing to process or there is an error.
+   */
+  protected function p_do_build_grant() {
+    $value = NULL;
+    if ($this->grant === e_database_grant::GRANT) {
+      $value = c_database_string::GRANT;
+    }
+    else if ($this->grant === e_database_grant::REVOKE) {
+      $value = c_database_string::REVOKE;
+    }
+
+    return $value;
+  }
+}
diff --git a/common/database/traits/database_in_schema.php b/common/database/traits/database_in_schema.php
index 56c8cbe..b977774 100644
--- a/common/database/traits/database_in_schema.php
+++ b/common/database/traits/database_in_schema.php
@@ -100,6 +100,6 @@ trait t_database_in_schema {
       return NULL;
     }
 
-    return c_database_string::IN . ' ' . c_database_string::SCHEMA . ' ' . implode(', ', $this->in_schema);
+    return c_database_string::IN_SCHEMA . ' ' . implode(', ', $this->in_schema);
   }
 }
diff --git a/common/database/traits/database_name.php b/common/database/traits/database_name.php
index 469df50..2e0b162 100644
--- a/common/database/traits/database_name.php
+++ b/common/database/traits/database_name.php
@@ -64,4 +64,21 @@ trait t_database_name {
     $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'name', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
     return c_base_return_error::s_null($error);
   }
+
+  /**
+   * Perform the common build process for this trait.
+   *
+   * As an internal trait method, the caller is expected to perform any appropriate validation.
+   *
+   * @return string|null
+   *   A string is returned on success.
+   *   NULL is returned if there is nothing to process or there is an error.
+   */
+  protected function p_do_build_name() {
+    if (is_null($this->name)) {
+      return NULL;
+    }
+
+    return $this->name;
+  }
 }
diff --git a/common/database/traits/database_on.php b/common/database/traits/database_on.php
new file mode 100644
index 0000000..b7b1477
--- /dev/null
+++ b/common/database/traits/database_on.php
@@ -0,0 +1,111 @@
+<?php
+/**
+ * @file
+ * Provides traits for specific Postgesql Queries.
+ *
+ * These traits are associated with on.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+require_once('common/base/classes/base_error.php');
+require_once('common/base/classes/base_return.php');
+
+require_once('common/database/classes/database_string.php');
+
+require_once('common/database/enumerations/database_on.php');
+
+require_once('common/database/enumerations/database_on.php');
+
+/**
+ * Provide the sql ON functionality.
+ */
+trait t_database_on {
+  protected $on;
+
+  /**
+   * Assigns the SQL ON operation.
+   *
+   * @param int|null $on
+   *   Whether or not to use the ON operation in the query.
+   *   Set to NULL to disable.
+   *
+   * @return c_base_return_status
+   *   TRUE on success, FALSE otherwise.
+   *   FALSE with error bit set is returned on error.
+   */
+  public function set_on($on) {
+    if (is_null($on)) {
+      $this->on = NULL;
+      return new c_base_return_true();
+    }
+
+    switch ($on) {
+      case e_database_on::TABLES_TO:
+      case e_database_on::SEQUENCES:
+      case e_database_on::FUNCTIONS:
+      case e_database_on::TYPES:
+      case e_database_on::SCHEMAS:
+        $this->on = $on;
+        return new c_base_return_true();
+      default:
+        break;
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'on', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+    return c_base_return_error::s_false($error);
+  }
+
+  /**
+   * Get the ON operation status.
+   *
+   * @return c_base_return_int|c_base_return_null
+   *   Integer representing the on operation is returned on success.
+   *   NULL is returned if undefined.
+   *   FALSE with error bit set is returned on error.
+   */
+  protected function get_on() {
+    if (is_null($this->on)) {
+      return new c_base_return_null();
+    }
+
+    return c_base_return_int::s_new($this->on);
+  }
+
+  /**
+   * Perform the common build process for this trait.
+   *
+   * As an internal trait method, the caller is expected to perform any appropriate validation.
+   *
+   * @return string|null
+   *   A string is returned on success.
+   *   NULL is returned if there is nothing to process or there is an error.
+   */
+  protected function p_do_build_on() {
+    if (is_null($this->on)) {
+      return NULL;
+    }
+
+    $value = NULL;
+    switch($this->on) {
+      case e_database_on::TABLES_TO:
+        $value .= c_database_string::ON_TABLES_TO;
+        break;
+      case e_database_on::SEQUENCES:
+        $value .= c_database_string::ON_SEQUENCES;
+        break;
+      case e_database_on::FUNCTIONS:
+        $value .= c_database_string::ON_FUNCTIONS;
+        break;
+      case e_database_on::TYPES:
+        $value .= c_database_string::ON_TYPES;
+        break;
+      case e_database_on::SCHEMAS:
+        $value .= c_database_string::ON_SCHEMAS;
+        break;
+    }
+
+    return $value;
+  }
+}
diff --git a/common/database/traits/database_privilege.php b/common/database/traits/database_privilege.php
new file mode 100644
index 0000000..b1bc778
--- /dev/null
+++ b/common/database/traits/database_privilege.php
@@ -0,0 +1,161 @@
+<?php
+/**
+ * @file
+ * Provides traits for specific Postgesql Queries.
+ *
+ * These traits are associated with actions.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+require_once('common/base/classes/base_error.php');
+require_once('common/base/classes/base_return.php');
+
+require_once('common/database/classes/database_string.php');
+
+/**
+ * Provide the sql PRIVILEGE functionality.
+ */
+trait t_database_privilege {
+  protected $privilege;
+
+  /**
+   * Assigns the SQL privileges.
+   *
+   * @param int|null $privilege
+   *   Set a privilege code.
+   *   Set to NULL to disable.
+   *   When NULL, this will remove all values.
+   *
+   * @return c_base_return_status
+   *   TRUE on success, FALSE otherwise.
+   *   FALSE with error bit set is returned on error.
+   */
+  public function set_privilege($privilege) {
+    if (is_null($privilege)) {
+      $this->privileges = NULL;
+      return new c_base_return_true();
+    }
+
+    if (is_int($privilege)) {
+      // no reason to add any privilege once ALL is present.
+      if ($this->privilege === e_database_privilege::ALL) {
+        return new c_base_return_true();
+      }
+
+      if ($privilege === e_database_privilege::ALL) {
+        $this->privilege = e_database_privilege::ALL;
+      }
+      else {
+        if (!is_array($this->privilege)) {
+          $this->privilege = [];
+        }
+
+        $this->privilege[] = $privilege;
+      }
+
+      return new c_base_return_true();
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'privilege', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+    return c_base_return_error::s_false($error);
+  }
+
+  /**
+   * Get the privileges.
+   *
+   * @param int|null $index
+   *   (optional) Get the privilege at the specified index.
+   *   When NULL, all privileges are returned.
+   *
+   * @return c_base_return_int|c_base_return_array|c_base_return_null
+   *   An array of privileges or NULL if not defined.
+   *   A single privilege is returned if $index is an integer.
+   *   NULL with the error bit set is returned on error.
+   */
+  public function get_privilege($index = NULL) {
+    if (is_null($this->privilege)) {
+      return new c_base_return_null();
+    }
+
+    if (is_null($index)) {
+      if ($this->privilege === e_database_privilege::ALL) {
+        return c_base_return_array::s_new([$this->privilege]);
+      }
+      else if (is_array($this->privilege)) {
+        return c_base_return_array::s_new($this->privilege);
+      }
+    }
+    else {
+      if (is_int($index) && array_key_exists($index, $this->privilege) && is_int($this->privilege[$index])) {
+        return clone($this->privilege[$index]);
+      }
+
+      $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'privilege[index]', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
+      return c_base_return_error::s_null($error);
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'privilege', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
+    return c_base_return_error::s_null($error);
+  }
+
+  /**
+   * Perform the common build process for this trait.
+   *
+   * As an internal trait method, the caller is expected to perform any appropriate validation.
+   *
+   * @return string|null
+   *   A string is returned on success.
+   *   NULL is returned if there is nothing to process or there is an error.
+   */
+  protected function p_do_build_privilege() {
+    if (is_null($this->privilege)) {
+      return NULL;
+    }
+
+    if ($this->privilege === e_database_privilege::ALL) {
+      return c_database_string::ALL;
+    }
+
+    $privileges = [];
+    foreach ($this->privilege as $privilege) {
+      switch ($privilege) {
+        case e_database_privilege::SELECT:
+          $privileges[] = c_database_string::SELECT;
+          break;
+        case e_database_privilege::INSERT:
+          $privileges[] = c_database_string::INSERT;
+          break;
+        case e_database_privilege::UPDATE:
+          $privileges[] = c_database_string::UPDATE;
+          break;
+        case e_database_privilege::DELETE:
+          $privileges[] = c_database_string::DELETE;
+          break;
+        case e_database_privilege::TRUNCATE:
+          $privileges[] = c_database_string::TRUNCATE;
+          break;
+        case e_database_privilege::REFERENCES:
+          $privileges[] = c_database_string::REFERENCES;
+          break;
+        case e_database_privilege::TRIGGER:
+          $privileges[] = c_database_string::TRIGGER;
+          break;
+        case e_database_privilege::USAGE:
+          $privileges[] = c_database_string::USAGE;
+          break;
+        case e_database_privilege::EXECUTE:
+          $privileges[] = c_database_string::EXECUTE;
+          break;
+        case e_database_privilege::CREATE:
+          $privileges[] = c_database_string::CREATE;
+          break;
+        default:
+          break;
+      }
+    }
+
+    return implode(', ', $privileges);
+  }
+}
diff --git a/common/database/traits/database_restrict.php b/common/database/traits/database_restrict.php
new file mode 100644
index 0000000..9e670e0
--- /dev/null
+++ b/common/database/traits/database_restrict.php
@@ -0,0 +1,87 @@
+<?php
+/**
+ * @file
+ * Provides traits for specific Postgesql Queries.
+ *
+ * These traits are associated with actions.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+require_once('common/base/classes/base_error.php');
+require_once('common/base/classes/base_return.php');
+
+require_once('common/database/classes/database_string.php');
+
+/**
+ * Provide the sql RESTRICT functionality.
+ */
+trait t_database_restrict {
+  protected $restrict;
+
+  /**
+   * Set the RESTRICT value.
+   *
+   * @param bool|null $restrict
+   *   Set to TRUE for RESTRICT.
+   *   Set to FALSE for not using RESTICT.
+   *   Set to NULL to disable.
+   *
+   * @return c_base_return_status
+   *   TRUE on success, FALSE otherwise.
+   *   FALSE with the error bit set is returned on error.
+   */
+  public function set_restrict($restrict) {
+    if (is_null($restrict)) {
+      $this->restrict = NULL;
+      return new c_base_return_true();
+    }
+
+    if (!is_bool($restrict)) {
+      $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'restrict', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+      return c_base_return_error::s_false($error);
+    }
+
+    $this->restrict = $restrict;
+    return new c_base_return_true();
+  }
+
+  /**
+   * Get the currently assigned restrict status.
+   *
+   * @return c_base_return_bool|c_base_return_null
+   *   TRUE for RESTRICT or FALSE for not using RESTRICT on success.
+   *   NULL is returned if not set.
+   *   NULL with the error bit set is returned on error.
+   */
+  public function get_restrict() {
+    if (is_null($this->restrict)) {
+      return new c_base_return_null();
+    }
+
+    if (is_bool($this->restrict)) {
+      return c_base_return_bool::s_new($this->restrict);
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'restrict', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
+    return c_base_return_error::s_null($error);
+  }
+
+  /**
+   * Perform the common build process for this trait.
+   *
+   * As an internal trait method, the caller is expected to perform any appropriate validation.
+   *
+   * @return string|null
+   *   A string is returned on success.
+   *   NULL is returned if there is nothing to process or there is an error.
+   */
+  protected function p_do_build_restrict() {
+    if (is_null($this->restrict)) {
+      return NULL;
+    }
+
+    return $this->restrict ? c_database_string::RESTRICT : NULL;
+  }
+}
diff --git a/common/database/traits/database_to_role.php b/common/database/traits/database_to_role.php
new file mode 100644
index 0000000..93e6e82
--- /dev/null
+++ b/common/database/traits/database_to_role.php
@@ -0,0 +1,135 @@
+<?php
+/**
+ * @file
+ * Provides traits for specific Postgesql Queries.
+ *
+ * These traits are associated with actions.
+ *
+ * @see: https://www.postgresql.org/docs/current/static/sql-commands.html
+ */
+namespace n_koopa;
+
+require_once('common/base/classes/base_error.php');
+require_once('common/base/classes/base_return.php');
+
+require_once('common/database/classes/database_string.php');
+
+require_once('common/database/enumerations/database_role.php');
+
+/**
+ * Provide the sql TO ROLES functionality.
+ */
+trait t_database_to_role {
+  protected $to_role;
+
+  /**
+   * Set the in schema, to roles.
+   *
+   * @param int|null $role_type
+   *   The role type to use.
+   *   Set to NULL to disable.
+   *   When NULL, this will remove all values.
+   * @param string|null $role_name
+   *   The role name to use.
+   *   This may be NULL if not used by the $role_type.
+   *
+   * @return c_base_return_status
+   *   TRUE on success, FALSE otherwise.
+   *   FALSE with error bit set is returned on error.
+   */
+  public function set_to_role($role_type, $role_name = NULL) {
+    if (is_null($role_type)) {
+      $this->to_role = NULL;
+      return new c_base_return_true();
+    }
+
+    if (is_int($role_type)) {
+      if ($role_type === e_database_role::NAME && !is_string($role_name) || !is_null($role_name) && !is_string($role_name)) {
+        $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'role_name', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+        return c_base_return_error::s_false($error);
+      }
+      else if ($role_type !== e_database_role::GROUP && $role_type !== e_database_role::PUBLIC) {
+        $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'role_type', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+        return c_base_return_error::s_false($error);
+      }
+
+      if (!is_array($this->to_role)) {
+        $this->to_role = [];
+      }
+
+      $this->to_role[] = [
+        'type' => $role_type,
+        'name' => $role_name,
+      ];
+      return new c_base_return_true();
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{argument_name}' => 'to_role', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_ARGUMENT);
+    return c_base_return_error::s_false($error);
+  }
+
+  /**
+   * Get the in schema, to roles.
+   *
+   * @param int|null $index
+   *   (optional) Get the schema name at the specified index.
+   *   When NULL, all to roles are returned.
+   *
+   * @return c_base_return_array|c_base_return_null
+   *   An array of to role arrays or NULL if not defined.
+   *   A single to role array is returned if $index is an integer.
+   *   NULL with the error bit set is returned on error.
+   */
+  public function get_to_role($index = NULL) {
+    if (is_null($this->to_role)) {
+      return new c_base_return_null();
+    }
+
+    if (is_null($index)) {
+      if (is_array($this->to_role)) {
+        return c_base_return_array::s_new($this->to_role);
+      }
+    }
+    else {
+      if (is_int($index) && array_key_exists($index, $this->to_role) && is_array($this->to_role[$index])) {
+        return c_base_return_array::s_new($this->to_role[$index]);
+      }
+
+      $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'to_role[index]', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
+      return c_base_return_error::s_null($error);
+    }
+
+    $error = c_base_error::s_log(NULL, ['arguments' => [':{variable_name}' => 'to_role', ':{function_name}' => __CLASS__ . '->' . __FUNCTION__]], i_base_error_messages::INVALID_VARIABLE);
+    return c_base_return_error::s_null($error);
+  }
+
+  /**
+   * Perform the common build process for this trait.
+   *
+   * As an internal trait method, the caller is expected to perform any appropriate validation.
+   *
+   * @return string|null
+   *   A string is returned on success.
+   *   NULL is returned if there is nothing to process or there is an error.
+   */
+  protected function p_do_build_to_role() {
+    if (is_null($this->to_role)) {
+      return NULL;
+    }
+
+    $values = [];
+    foreach ($this->to_role as $to_role) {
+      if ($this->to_role['type'] === e_database_role::PUBLIC) {
+        $values[] = c_database_string::PUBLIC;
+      }
+      else if ($this->to_role['type'] === e_database_role::GROUP) {
+        $values[] = c_database_string::GROUP;
+      }
+      else if ($this->to_role['type'] === e_database_role::NAME) {
+        $values[] = $this->to_role['name'];
+      }
+    }
+
+    return c_database_string::TO . ' ' . implode(', ', $values);
+  }
+}