[Summary view] [Print] [Text view]

   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  }