WP Merge to revision 8180

git-svn-id: http://svn.automattic.com/wordpress-mu/trunk@1336 7be80a69-a1ef-0310-a953-fb0f7c49ff36

1 files changed, 466 insertions, 85 deletions

diff --git a/wp-includes/wp-db.php b/wp-includes/wp-db.php
index 00c7e81..74e38ea 100644
--- a/wp-includes/wp-db.php
+++ b/wp-includes/wp-db.php
@@ -1,66 +1,298 @@
 <?php
-//  WordPress DB Class
-
-//  ORIGINAL CODE FROM:
-//  Justin Vincent (justin@visunet.ie)
-//	http://php.justinvincent.com
-
+/**
+ * WordPress DB Class
+ *
+ * Original code from {@link http://php.justinvincent.com Justin Vincent (justin@visunet.ie)}
+ *
+ * @package WordPress
+ * @subpackage Database
+ * @since 0.71
+ */
+
+/**
+ * @since 0.71
+ */
 define('EZSQL_VERSION', 'WP1.25');
+
+/**
+ * @since 0.71
+ */
 define('OBJECT', 'OBJECT', true);
+
+/**
+ * @since {@internal Version Unknown}}
+ */
 define('OBJECT_K', 'OBJECT_K', false);
+
+/**
+ * @since 0.71
+ */
 define('ARRAY_A', 'ARRAY_A', false);
-define('ARRAY_N', 'ARRAY_N', false);
 
-if (!defined('SAVEQUERIES'))
-	define('SAVEQUERIES', false);
+/**
+ * @since 0.71
+ */
+define('ARRAY_N', 'ARRAY_N', false);
 
+/**
+ * WordPress Database Access Abstraction Object
+ *
+ * It is possible to replace this class with your own
+ * by setting the $wpdb global variable in wp-content/wpdb.php
+ * file with your class. You can name it wpdb also, since
+ * this file will not be included, if the other file is
+ * available.
+ *
+ * @link http://codex.wordpress.org/Function_Reference/wpdb_Class
+ *
+ * @package WordPress
+ * @subpackage Database
+ * @since 0.71
+ * @final
+ */
 class wpdb {
 
+	/**
+	 * Whether to show SQL/DB errors
+	 *
+	 * @since 0.71
+	 * @access private
+	 * @var bool
+	 */
 	var $show_errors = false;
+
+	/**
+	 * Whether to suppress errors during the DB bootstrapping.
+	 *
+	 * @access private
+	 * @since {@internal Version Unknown}}
+	 * @var bool
+	 */
 	var $suppress_errors = false;
+
+	/**
+	 * The last error during query.
+	 *
+	 * @since {@internal Version Unknown}}
+	 * @var string
+	 */
 	var $last_error = '';
+
+	/**
+	 * Amount of queries made
+	 *
+	 * @since 1.2.0
+	 * @access private
+	 * @var int
+	 */
 	var $num_queries = 0;
+
+	/**
+	 * Saved result of the last query made
+	 *
+	 * @since 1.2.0
+	 * @access private
+	 * @var array
+	 */
 	var $last_query;
+
+	/**
+	 * Saved info on the table column
+	 *
+	 * @since 1.2.0
+	 * @access private
+	 * @var array
+	 */
 	var $col_info;
+
+	/**
+	 * Saved queries that were executed
+	 *
+	 * @since 1.5.0
+	 * @access private
+	 * @var array
+	 */
 	var $queries;
+
+	/**
+	 * WordPress table prefix
+	 *
+	 * You can set this to have multiple WordPress installations
+	 * in a single database. The second reason is for possible
+	 * security precautions.
+	 *
+	 * @since 0.71
+	 * @access private
+	 * @var string
+	 */
 	var $prefix = '';
+
+	/**
+	 * Whether the database queries are ready to start executing.
+	 *
+	 * @since 2.5.0
+	 * @access private
+	 * @var bool
+	 */
 	var $ready = false;
 	var $blogid = 0;
 	var $siteid = 0;
-
-	// Global tables
 	var $blogs;
 	var $signups;
 	var $site;
 	var $sitemeta;
-	var $users;
 	var $usermeta;
 	var $sitecategories;
 	var $global_tables = array('blogs', 'signups', 'site', 'sitemeta', 'users', 'usermeta', 'sitecategories', 'registration_log', 'blog_versions');
 
-	// Blog tables
+	/**
+	 * WordPress Posts table
+	 *
+	 * @since 1.5.0
+	 * @access public
+	 * @var string
+	 */
 	var $posts;
+
+	/**
+	 * WordPress Users table
+	 *
+	 * @since 1.5.0
+	 * @access public
+	 * @var string
+	 */
+	var $users;
+
+	/**
+	 * WordPress Categories table
+	 *
+	 * @since 1.5.0
+	 * @access public
+	 * @var string
+	 */
 	var $categories;
+
+	/**
+	 * WordPress Post to Category table
+	 *
+	 * @since 1.5.0
+	 * @access public
+	 * @var string
+	 */
 	var $post2cat;
+
+	/**
+	 * WordPress Comments table
+	 *
+	 * @since 1.5.0
+	 * @access public
+	 * @var string
+	 */
 	var $comments;
+
+	/**
+	 * WordPress Links table
+	 *
+	 * @since 1.5.0
+	 * @access public
+	 * @var string
+	 */
 	var $links;
+
+	/**
+	 * WordPress Options table
+	 *
+	 * @since 1.5.0
+	 * @access public
+	 * @var string
+	 */
 	var $options;
+
+	/**
+	 * WordPress Post Metadata table
+	 *
+	 * @since {@internal Version Unknown}}
+	 * @access public
+	 * @var string
+	 */
 	var $postmeta;
+
+	/**
+	 * WordPress User Metadata table
+	 *
+	 * @since 2.3.0
+	 * @access public
+	 * @var string
+	 */
+	var $usermeta;
+
+	/**
+	 * WordPress Terms table
+	 *
+	 * @since 2.3.0
+	 * @access public
+	 * @var string
+	 */
 	var $terms;
+
+	/**
+	 * WordPress Term Taxonomy table
+	 *
+	 * @since 2.3.0
+	 * @access public
+	 * @var string
+	 */
 	var $term_taxonomy;
+
+	/**
+	 * WordPress Term Relationships table
+	 *
+	 * @since 2.3.0
+	 * @access public
+	 * @var string
+	 */
 	var $term_relationships;
+
+	/**
+	 * List of WordPress tables
+	 *
+	 * @since {@internal Version Unknown}}
+	 * @access private
+	 * @var array
+	 */
 	var $blog_tables = array('posts', 'categories', 'post2cat', 'comments', 'links', 'link2cat', 'options',
 			'postmeta', 'terms', 'term_taxonomy', 'term_relationships');
 
+	/**
+	 * Database table columns charset
+	 *
+	 * @since 2.2.0
+	 * @access public
+	 * @var string
+	 */
 	var $charset;
+
+	/**
+	 * Database table columns collate
+	 *
+	 * @since 2.2.0
+	 * @access public
+	 * @var string
+	 */
 	var $collate;
 
 	/**
 	 * Connects to the database server and selects a database
-	 * @param string $dbuser
-	 * @param string $dbpassword
-	 * @param string $dbname
-	 * @param string $dbhost
+	 *
+	 * PHP4 compatibility layer for calling the PHP5 constructor.
+	 *
+	 * @uses wpdb::__construct() Passes parameters and returns result
+	 * @since 0.71
+	 *
+	 * @param string $dbuser MySQL database user
+	 * @param string $dbpassword MySQL database password
+	 * @param string $dbname MySQL database name
+	 * @param string $dbhost MySQL database host
 	 */
 	function wpdb($dbuser, $dbpassword, $dbname, $dbhost) {
 		if( defined( "WP_USE_MULTIPLE_DB" ) && CONSTANT( "WP_USE_MULTIPLE_DB" ) == true )
@@ -68,6 +300,20 @@ class wpdb {
 		return $this->__construct($dbuser, $dbpassword, $dbname, $dbhost);
 	}
 
+	/**
+	 * Connects to the database server and selects a database
+	 *
+	 * PHP5 style constructor for compatibility with PHP5. Does
+	 * the actual setting up of the class properties and connection
+	 * to the database.
+	 *
+	 * @since 2.0.8
+	 *
+	 * @param string $dbuser MySQL database user
+	 * @param string $dbpassword MySQL database password
+	 * @param string $dbname MySQL database name
+	 * @param string $dbhost MySQL database host
+	 */
 	function __construct($dbuser, $dbpassword, $dbname, $dbhost) {
 		register_shutdown_function(array(&$this, "__destruct"));
 
@@ -89,16 +335,16 @@ class wpdb {
 
 		$this->dbh = @mysql_connect($dbhost, $dbuser, $dbpassword, true);
 		if (!$this->dbh) {
-			$this->bail("
+			$this->bail(sprintf(/*WP_I18N_DB_CONN_ERROR*/"
 <h1>Error establishing a database connection</h1>
-<p>This either means that the username and password information in your <code>wp-config.php</code> file is incorrect or we can't contact the database server at <code>$dbhost</code>. This could mean your host's database server is down.</p>
+<p>This either means that the username and password information in your <code>wp-config.php</code> file is incorrect or we can't contact the database server at <code>%s</code>. This could mean your host's database server is down.</p>
 <ul>
 	<li>Are you sure you have the correct username and password?</li>
 	<li>Are you sure that you have typed the correct hostname?</li>
 	<li>Are you sure that the database server is running?</li>
 </ul>
 <p>If you're unsure what these terms mean you should probably contact your host. If you still need help you can always visit the <a href='http://wordpress.org/support/'>WordPress Support Forums</a>.</p>
-");
+"/*/WP_I18N_DB_CONN_ERROR*/, $dbhost));
 			return;
 		}
 
@@ -120,14 +366,32 @@ class wpdb {
 		$this->select($dbname, $this->dbh);
 	}
 
+	/**
+	 * PHP5 style destructor and will run when database object is destroyed.
+	 *
+	 * @since 2.0.8
+	 *
+	 * @return bool Always true
+	 */
 	function __destruct() {
 		return true;
 	}
 
+	/**
+	 * Sets the table prefix for the WordPress tables.
+	 *
+	 * Also allows for the CUSTOM_USER_TABLE and CUSTOM_USER_META_TABLE to
+	 * override the WordPress users and usersmeta tables.
+	 *
+	 * @since 2.5.0
+	 *
+	 * @param string $prefix Alphanumeric name for the new prefix.
+	 * @return string Old prefix
+	 */
 	function set_prefix($prefix) {
 
 		if ( preg_match('|[^a-z0-9_]|i', $prefix) )
-			return new WP_Error('invalid_db_prefix', 'Invalid database prefix'); // No gettext here
+			return new WP_Error('invalid_db_prefix', /*WP_I18N_DB_BAD_PREFIX*/'Invalid database prefix'/*/WP_I18N_DB_BAD_PREFIX*/);
 
 		$old_prefix = $this->base_prefix;
 		$this->base_prefix = $prefix;
@@ -168,21 +432,28 @@ class wpdb {
 
 
 	/**
-	 * Selects a database using the current class's $this->dbh
-	 * @param string $db name
+	 * Selects a database using the current database connection.
+	 *
+	 * The database name will be changed based on the current database
+	 * connection. On failure, the execution will bail and display an DB error.
+	 *
+	 * @since 0.71
+	 *
+	 * @param string $db MySQL database name
+	 * @return null Always null.
 	 */
 	function select($db, &$dbh) {
 		if (!@mysql_select_db($db, $dbh)) {
 			$this->ready = false;
-			$this->bail("
+			$this->bail(sprintf(/*WP_I18N_DB_SELECT_DB*/'
 <h1>Can&#8217;t select database</h1>
-<p>We were able to connect to the database server (which means your username and password is okay) but not able to select the <code>$db</code> database.</p>
+<p>We were able to connect to the database server (which means your username and password is okay) but not able to select the <code>%1$s</code> database.</p>
 <ul>
 <li>Are you sure it exists?</li>
-<li>Does the user <code>".DB_USER."</code> have permission to use the <code>$db</code> database?</li>
+<li>Does the user <code>%2$s</code> have permission to use the <code>%1$s</code> database?</li>
 <li>On some systems the name of your database is prefixed with your username, so it would be like username_wordpress. Could that be the problem?</li>
 </ul>
-<p>If you don't know how to setup a database you should <strong>contact your host</strong>. If all else fails you may find help at the <a href='http://wordpress.org/support/'>WordPress Support Forums</a>.</p>");
+<p>If you don\'t know how to setup a database you should <strong>contact your host</strong>. If all else fails you may find help at the <a href="http://wordpress.org/support/">WordPress Support Forums</a>.</p>'/*/WP_I18N_DB_SELECT_DB*/, $db, DB_USER));
 			return;
 		}
 	}
@@ -190,6 +461,8 @@ class wpdb {
 	/**
 	 * Escapes content for insertion into the database, for security
 	 *
+	 * @since 0.71
+	 *
 	 * @param string $string
 	 * @return string query safe string
 	 */
@@ -206,6 +479,9 @@ class wpdb {
 
 	/**
 	 * Escapes content by reference for insertion into the database, for security
+	 *
+	 * @since 2.3.0
+	 *
 	 * @param string $s
 	 */
 	function escape_by_ref(&$s) {
@@ -213,10 +489,17 @@ class wpdb {
 	}
 
 	/**
-	 * Prepares a SQL query for safe use, using sprintf() syntax
+	 * Prepares a SQL query for safe use, using sprintf() syntax.
+	 *
+	 * @link http://php.net/sprintf See for syntax to use for query string.
+	 * @since 2.3.0
+	 *
+	 * @param null|string $args If string, first parameter must be query statement
+	 * @param mixed $args,... If additional parameters, they will be set inserted into the query.
+	 * @return null|string Sanitized query string
 	 */
-	function prepare($args=NULL) {
-		if ( NULL === $args )
+	function prepare($args=null) {
+		if ( is_null( $args ) )
 			return;
 		$args = func_get_args();
 		$query = array_shift($args);
@@ -227,22 +510,28 @@ class wpdb {
 		return @vsprintf($query, $args);
 	}
 
-	// ==================================================================
-	//	Print SQL/DB error.
-
+	/**
+	 * Print SQL/DB error.
+	 *
+	 * @since 0.71
+	 * @global array $EZSQL_ERROR Stores error information of query and error string
+	 *
+	 * @param string $str The error to display
+	 * @return bool False if the showing of errors is disabled.
+	 */
 	function print_error($str = '') {
 		global $EZSQL_ERROR;
 
 		if (!$str) $str = mysql_error($this->dbh);
-		$EZSQL_ERROR[] =
-		array ('query' => $this->last_query, 'error_str' => $str);
+		$EZSQL_ERROR[] = array ('query' => $this->last_query, 'error_str' => $str);
 
 		if ( $this->suppress_errors )
 			return false;
 
-		$error_str = "WordPress database error $str for query $this->last_query";
 		if ( $caller = $this->get_caller() )
-			$error_str .= " made by $caller";
+			$error_str = sprintf(/*WP_I18N_DB_QUERY_ERROR_FULL*/'WordPress database error %1$s for query %2$s made by %3$s'/*/WP_I18N_DB_QUERY_ERROR_FULL*/, $str, $this->last_query, $caller);
+		else
+			$error_str = sprintf(/*WP_I18N_DB_QUERY_ERROR*/'WordPress database error %1$s for query %2$s'/*/WP_I18N_DB_QUERY_ERROR*/, $str, $this->last_query);
 
 		$log_error = true;
 		if ( ! function_exists('error_log') )
@@ -267,30 +556,55 @@ class wpdb {
 			die( $msg );
 	}
 
-	// ==================================================================
-	//	Turn error handling on or off..
-
+	/**
+	 * Enables showing of database errors.
+	 *
+	 * This function should be used only to enable showing of errors.
+	 * wpdb::hide_errors() should be used instead for hiding of errors. However,
+	 * this function can be used to enable and disable showing of database
+	 * errors.
+	 *
+	 * @since 0.71
+	 *
+	 * @param bool $show Whether to show or hide errors
+	 * @return bool Old value for showing errors.
+	 */
 	function show_errors( $show = true ) {
 		$errors = $this->show_errors;
 		$this->show_errors = $show;
 		return $errors;
 	}
 
+	/**
+	 * Disables showing of database errors.
+	 *
+	 * @since 0.71
+	 *
+	 * @return bool Whether showing of errors was active or not
+	 */
 	function hide_errors() {
 		$show = $this->show_errors;
 		$this->show_errors = false;
 		return $show;
 	}
 
+	/**
+	 * Whether to suppress database errors.
+	 *
+	 * @param unknown_type $suppress
+	 * @return unknown
+	 */
 	function suppress_errors( $suppress = true ) {
 		$errors = $this->suppress_errors;
 		$this->suppress_errors = $suppress;
 		return $errors;
 	}
 
-	// ==================================================================
-	//	Kill cached query results
-
+	/**
+	 * Kill cached query results.
+	 *
+	 * @since 0.71
+	 */
 	function flush() {
 		$this->last_result = array();
 		$this->col_info = null;
@@ -333,9 +647,16 @@ class wpdb {
 		$this->select( $details[ 'db_name' ], $this->$dbhname );
 	}
 
-	// ==================================================================
-	//	Basic Query	- see docs for more detail
-
+	/**
+	 * Perform a MySQL database query, using current database connection.
+	 *
+	 * More information can be found on the codex page.
+	 *
+	 * @since 0.71
+	 *
+	 * @param string $query
+	 * @return unknown
+	 */
 	function query($query) {
 		if ( ! $this->ready )
 			return false;
@@ -356,7 +677,7 @@ class wpdb {
 		$this->last_query = $query;
 
 		// Perform the query via std mysql_query function..
-		if (SAVEQUERIES)
+		if ( defined('SAVEQUERIES') && SAVEQUERIES )
 			$this->timer_start();
 		
 		// use $this->dbh for read ops, and $this->dbhwrite for write ops
@@ -387,7 +708,7 @@ class wpdb {
 		$this->result = @mysql_query($query, $dbh);
 		++$this->num_queries;
 
-		if (SAVEQUERIES)
+		if ( defined('SAVEQUERIES') && SAVEQUERIES )
 			$this->queries[] = array( $query, $this->timer_stop(), $this->get_caller() );
 
 		// If there is an error then take note of it..
@@ -431,10 +752,13 @@ class wpdb {
 	}
 
 	/**
-	 * Insert an array of data into a table
+	 * Insert an array of data into a table.
+	 *
+	 * @since 2.5.0
+	 *
 	 * @param string $table WARNING: not sanitized!
-	 * @param array $data should not already be SQL-escaped
-	 * @return mixed results of $this->query()
+	 * @param array $data Should not already be SQL-escaped
+	 * @return mixed Results of $this->query()
 	 */
 	function insert($table, $data) {
 		$data = add_magic_quotes($data);
@@ -443,11 +767,14 @@ class wpdb {
 	}
 
 	/**
-	 * Update a row in the table with an array of data
+	 * Update a row in the table with an array of data.
+	 *
+	 * @since 2.5.0
+	 *
 	 * @param string $table WARNING: not sanitized!
-	 * @param array $data should not already be SQL-escaped
-	 * @param array $where a named array of WHERE column => value relationships.  Multiple member pairs will be joined with ANDs.  WARNING: the column names are not currently sanitized!
-	 * @return mixed results of $this->query()
+	 * @param array $data Should not already be SQL-escaped
+	 * @param array $where A named array of WHERE column => value relationships.  Multiple member pairs will be joined with ANDs.  WARNING: the column names are not currently sanitized!
+	 * @return mixed Results of $this->query()
 	 */
 	function update($table, $data, $where){
 		$data = add_magic_quotes($data);
@@ -464,11 +791,21 @@ class wpdb {
 	}
 
 	/**
-	 * Get one variable from the database
-	 * @param string $query (can be null as well, for caching, see codex)
-	 * @param int $x = 0 row num to return
-	 * @param int $y = 0 col num to return
-	 * @return mixed results
+	 * Retrieve one variable from the database.
+	 *
+	 * This combines the functionality of wpdb::get_row() and wpdb::get_col(),
+	 * so both the column and row can be picked.
+	 *
+	 * It is possible to use this function without executing more queries. If
+	 * you already made a query, you can set the $query to 'null' value and just
+	 * retrieve either the column and row of the last query result.
+	 *
+	 * @since 0.71
+	 *
+	 * @param string $query Can be null as well, for caching
+	 * @param int $x Column num to return
+	 * @param int $y Row num to return
+	 * @return mixed Database query results
 	 */
 	function get_var($query=null, $x = 0, $y = 0) {
 		$this->func_call = "\$db->get_var(\"$query\",$x,$y)";
@@ -485,11 +822,14 @@ class wpdb {
 	}
 
 	/**
-	 * Get one row from the database
-	 * @param string $query
+	 * Retrieve one row from the database.
+	 *
+	 * @since 0.71
+	 *
+	 * @param string $query SQL query
 	 * @param string $output ARRAY_A | ARRAY_N | OBJECT
-	 * @param int $y row num to return
-	 * @return mixed results
+	 * @param int $y Row num to return
+	 * @return mixed Database query results
 	 */
 	function get_row($query = null, $output = OBJECT, $y = 0) {
 		$this->func_call = "\$db->get_row(\"$query\",$output,$y)";
@@ -508,15 +848,18 @@ class wpdb {
 		} elseif ( $output == ARRAY_N ) {
 			return $this->last_result[$y] ? array_values(get_object_vars($this->last_result[$y])) : null;
 		} else {
-			$this->print_error(" \$db->get_row(string query, output type, int offset) -- Output type must be one of: OBJECT, ARRAY_A, ARRAY_N");
+			$this->print_error(/*WP_I18N_DB_GETROW_ERROR*/" \$db->get_row(string query, output type, int offset) -- Output type must be one of: OBJECT, ARRAY_A, ARRAY_N"/*/WP_I18N_DB_GETROW_ERROR*/);
 		}
 	}
 
 	/**
-	 * Gets one column from the database
-	 * @param string $query (can be null as well, for caching, see codex)
-	 * @param int $x col num to return
-	 * @return array results
+	 * Retrieve one column from the database.
+	 *
+	 * @since 0.71
+	 *
+	 * @param string $query Can be null as well, for caching
+	 * @param int $x Col num to return. Starts from 0.
+	 * @return array Column results
 	 */
 	function get_col($query = null , $x = 0) {
 		if ( $query )
@@ -531,10 +874,13 @@ class wpdb {
 	}
 
 	/**
-	 * Return an entire result set from the database
-	 * @param string $query (can also be null to pull from the cache)
+	 * Retrieve an entire result set from the database.
+	 *
+	 * @since 0.71
+	 *
+	 * @param string|null $query Can also be null to pull from the cache
 	 * @param string $output ARRAY_A | ARRAY_N | OBJECT_K | OBJECT
-	 * @return mixed results
+	 * @return mixed Database query results
 	 */
 	function get_results($query = null, $output = OBJECT) {
 		$this->func_call = "\$db->get_results(\"$query\", $output)";
@@ -576,10 +922,13 @@ class wpdb {
 	}
 
 	/**
-	 * Grabs column metadata from the last query
+	 * Retrieve column metadata from the last query.
+	 *
+	 * @since 0.71
+	 *
 	 * @param string $info_type one of name, table, def, max_length, not_null, primary_key, multiple_key, unique_key, numeric, blob, type, unsigned, zerofill
 	 * @param int $col_offset 0: col name. 1: which table the col's in. 2: col's max length. 3: if the col is numeric. 4: col's type
-	 * @return mixed results
+	 * @return mixed Column Results
 	 */
 	function get_col_info($info_type = 'name', $col_offset = -1) {
 		if ( $this->col_info ) {
@@ -597,7 +946,11 @@ class wpdb {
 	}
 
 	/**
-	 * Starts the timer, for debugging purposes
+	 * Starts the timer, for debugging purposes.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @return bool Always returns true
 	 */
 	function timer_start() {
 		$mtime = microtime();
@@ -607,8 +960,11 @@ class wpdb {
 	}
 
 	/**
-	 * Stops the debugging timer
-	 * @return int total time spent on the query, in milliseconds
+	 * Stops the debugging timer.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @return int Total time spent on the query, in milliseconds
 	 */
 	function timer_stop() {
 		$mtime = microtime();
@@ -620,9 +976,13 @@ class wpdb {
 
 	/**
 	 * Wraps fatal errors in a nice header and footer and dies.
+	 *
+	 * @since 1.5.0
+	 *
 	 * @param string $message
+	 * @return unknown
 	 */
-	function bail($message) { // Just wraps errors in a nice header and footer
+	function bail($message) {
 		if ( !$this->show_errors ) {
 			if ( class_exists('WP_Error') )
 				$this->error = new WP_Error('500', $message);
@@ -634,8 +994,12 @@ class wpdb {
 	}
 
 	/**
-	 * Checks wether of not the database version is high enough to support the features WordPress uses
-	 * @global $wp_version
+	 * Whether or not MySQL database is minimal required version.
+	 *
+	 * @since 2.5.0
+	 * @uses $wp_version
+	 *
+	 * @return WP_Error
 	 */
 	function check_database_version()
 	{
@@ -647,8 +1011,13 @@ class wpdb {
 	}
 
 	/**
-	 * This function is called when WordPress is generating the table schema to determine wether or not the current database
-	 * supports or needs the collation statements.
+	 * Whether of not the database version supports collation.
+	 *
+	 * Called when WordPress is generating the table scheme.
+	 *
+	 * @since 2.5.0
+	 *
+	 * @return bool True if collation is supported, false if version does not
 	 */
 	function supports_collation()
 	{
@@ -656,8 +1025,14 @@ class wpdb {
 	}
 
 	/**
-	 * Get the name of the function that called wpdb.
-	 * @return string the name of the calling function
+	 * Retrieve the name of the function that called wpdb.
+	 *
+	 * Requires PHP 4.3 and searches up the list of functions until it reaches
+	 * the one that would most logically had called this method.
+	 *
+	 * @since 2.5.0
+	 *
+	 * @return string The name of the calling function
 	 */
 	function get_caller() {
 		// requires PHP 4.3+
@@ -685,6 +1060,12 @@ class wpdb {
 
 }
 
-if ( ! isset($wpdb) )
+if ( ! isset($wpdb) ) {
+	/**
+	 * WordPress Database Object, if it isn't set already in wp-content/wpdb.php
+	 * @global object $wpdb Creates a new wpdb object based on wp-config.php Constants for the database
+	 * @since 0.71
+	 */
 	$wpdb = new wpdb(DB_USER, DB_PASSWORD, DB_NAME, DB_HOST);
+}
 ?>