wp/wp-admin/install-helper.php
changeset 0 d970ebf37754
child 5 5e2f62d02dcd
equal deleted inserted replaced
-1:000000000000 0:d970ebf37754
       
     1 <?php
       
     2 /**
       
     3  * Plugins may load this file to gain access to special helper functions for
       
     4  * plugin installation. This file is not included by WordPress and it is
       
     5  * recommended, to prevent fatal errors, that this file is included using
       
     6  * require_once().
       
     7  *
       
     8  * These functions are not optimized for speed, but they should only be used
       
     9  * once in a while, so speed shouldn't be a concern. If it is and you are
       
    10  * needing to use these functions a lot, you might experience time outs. If you
       
    11  * do, then it is advised to just write the SQL code yourself.
       
    12  *
       
    13  * <code>
       
    14  * check_column('wp_links', 'link_description', 'mediumtext');
       
    15  * if (check_column($wpdb->comments, 'comment_author', 'tinytext'))
       
    16  *     echo "ok\n";
       
    17  *
       
    18  * $error_count = 0;
       
    19  * $tablename = $wpdb->links;
       
    20  * // check the column
       
    21  * if (!check_column($wpdb->links, 'link_description', 'varchar(255)')) {
       
    22  *     $ddl = "ALTER TABLE $wpdb->links MODIFY COLUMN link_description varchar(255) NOT NULL DEFAULT '' ";
       
    23  *     $q = $wpdb->query($ddl);
       
    24  * }
       
    25  *
       
    26  * if (check_column($wpdb->links, 'link_description', 'varchar(255)')) {
       
    27  *     $res .= $tablename . ' - ok <br />';
       
    28  * } else {
       
    29  *     $res .= 'There was a problem with ' . $tablename . '<br />';
       
    30  *     ++$error_count;
       
    31  * }
       
    32  * </code>
       
    33  *
       
    34  * @package WordPress
       
    35  * @subpackage Plugin
       
    36  */
       
    37 
       
    38 /** Load WordPress Bootstrap */
       
    39 require_once(dirname(dirname(__FILE__)).'/wp-load.php');
       
    40 
       
    41 if ( ! function_exists('maybe_create_table') ) :
       
    42 /**
       
    43  * Create database table, if it doesn't already exist.
       
    44  *
       
    45  * @since 1.0.0
       
    46  * @package WordPress
       
    47  * @subpackage Plugin
       
    48  * @uses $wpdb
       
    49  *
       
    50  * @param string $table_name Database table name.
       
    51  * @param string $create_ddl Create database table SQL.
       
    52  * @return bool False on error, true if already exists or success.
       
    53  */
       
    54 function maybe_create_table($table_name, $create_ddl) {
       
    55 	global $wpdb;
       
    56 	foreach ($wpdb->get_col("SHOW TABLES",0) as $table ) {
       
    57 		if ($table == $table_name) {
       
    58 			return true;
       
    59 		}
       
    60 	}
       
    61 	//didn't find it try to create it.
       
    62 	$wpdb->query($create_ddl);
       
    63 	// we cannot directly tell that whether this succeeded!
       
    64 	foreach ($wpdb->get_col("SHOW TABLES",0) as $table ) {
       
    65 		if ($table == $table_name) {
       
    66 			return true;
       
    67 		}
       
    68 	}
       
    69 	return false;
       
    70 }
       
    71 endif;
       
    72 
       
    73 if ( ! function_exists('maybe_add_column') ) :
       
    74 /**
       
    75  * Add column to database table, if column doesn't already exist in table.
       
    76  *
       
    77  * @since 1.0.0
       
    78  * @package WordPress
       
    79  * @subpackage Plugin
       
    80  * @uses $wpdb
       
    81  *
       
    82  * @param string $table_name Database table name
       
    83  * @param string $column_name Table column name
       
    84  * @param string $create_ddl SQL to add column to table.
       
    85  * @return bool False on failure. True, if already exists or was successful.
       
    86  */
       
    87 function maybe_add_column($table_name, $column_name, $create_ddl) {
       
    88 	global $wpdb;
       
    89 	foreach ($wpdb->get_col("DESC $table_name",0) as $column ) {
       
    90 
       
    91 		if ($column == $column_name) {
       
    92 			return true;
       
    93 		}
       
    94 	}
       
    95 	//didn't find it try to create it.
       
    96 	$wpdb->query($create_ddl);
       
    97 	// we cannot directly tell that whether this succeeded!
       
    98 	foreach ($wpdb->get_col("DESC $table_name",0) as $column ) {
       
    99 		if ($column == $column_name) {
       
   100 			return true;
       
   101 		}
       
   102 	}
       
   103 	return false;
       
   104 }
       
   105 endif;
       
   106 
       
   107 /**
       
   108  * Drop column from database table, if it exists.
       
   109  *
       
   110  * @since 1.0.0
       
   111  * @package WordPress
       
   112  * @subpackage Plugin
       
   113  * @uses $wpdb
       
   114  *
       
   115  * @param string $table_name Table name
       
   116  * @param string $column_name Column name
       
   117  * @param string $drop_ddl SQL statement to drop column.
       
   118  * @return bool False on failure, true on success or doesn't exist.
       
   119  */
       
   120 function maybe_drop_column($table_name, $column_name, $drop_ddl) {
       
   121 	global $wpdb;
       
   122 	foreach ($wpdb->get_col("DESC $table_name",0) as $column ) {
       
   123 		if ($column == $column_name) {
       
   124 			//found it try to drop it.
       
   125 			$wpdb->query($drop_ddl);
       
   126 			// we cannot directly tell that whether this succeeded!
       
   127 			foreach ($wpdb->get_col("DESC $table_name",0) as $column ) {
       
   128 				if ($column == $column_name) {
       
   129 					return false;
       
   130 				}
       
   131 			}
       
   132 		}
       
   133 	}
       
   134 	// else didn't find it
       
   135 	return true;
       
   136 }
       
   137 
       
   138 /**
       
   139  * Check column matches criteria.
       
   140  *
       
   141  * Uses the SQL DESC for retrieving the table info for the column. It will help
       
   142  * understand the parameters, if you do more research on what column information
       
   143  * is returned by the SQL statement. Pass in null to skip checking that
       
   144  * criteria.
       
   145  *
       
   146  * Column names returned from DESC table are case sensitive and are listed:
       
   147  *      Field
       
   148  *      Type
       
   149  *      Null
       
   150  *      Key
       
   151  *      Default
       
   152  *      Extra
       
   153  *
       
   154  * @since 1.0.0
       
   155  * @package WordPress
       
   156  * @subpackage Plugin
       
   157  *
       
   158  * @param string $table_name Table name
       
   159  * @param string $col_name Column name
       
   160  * @param string $col_type Column type
       
   161  * @param bool $is_null Optional. Check is null.
       
   162  * @param mixed $key Optional. Key info.
       
   163  * @param mixed $default Optional. Default value.
       
   164  * @param mixed $extra Optional. Extra value.
       
   165  * @return bool True, if matches. False, if not matching.
       
   166  */
       
   167 function check_column($table_name, $col_name, $col_type, $is_null = null, $key = null, $default = null, $extra = null) {
       
   168 	global $wpdb;
       
   169 	$diffs = 0;
       
   170 	$results = $wpdb->get_results("DESC $table_name");
       
   171 
       
   172 	foreach ($results as $row ) {
       
   173 
       
   174 		if ($row->Field == $col_name) {
       
   175 			// got our column, check the params
       
   176 			if (($col_type != null) && ($row->Type != $col_type)) {
       
   177 				++$diffs;
       
   178 			}
       
   179 			if (($is_null != null) && ($row->Null != $is_null)) {
       
   180 				++$diffs;
       
   181 			}
       
   182 			if (($key != null) && ($row->Key  != $key)) {
       
   183 				++$diffs;
       
   184 			}
       
   185 			if (($default != null) && ($row->Default != $default)) {
       
   186 				++$diffs;
       
   187 			}
       
   188 			if (($extra != null) && ($row->Extra != $extra)) {
       
   189 				++$diffs;
       
   190 			}
       
   191 			if ($diffs > 0) {
       
   192 				return false;
       
   193 			}
       
   194 			return true;
       
   195 		} // end if found our column
       
   196 	}
       
   197 	return false;
       
   198 }