Converting mysql_query to $wpdb->get_results

问题

Afetr updating php on the server i have some problems with mysql_query. There are 2 functions in your code that have been deprecated in the current version of PHP : mysql_fetch_array() mysql_query()

   global $table_prefix, $wpdb;
// caching database query per comment
$ck_cache = array('ck_ips'=>"", 'ck_comment_id'=>0, 'ck_rating_up'=>0, 'ck_rating_down'=>0); 

$table_name = $table_prefix . "comment_rating";
if($wpdb->get_var("SHOW TABLES LIKE '$table_name'") != $table_name)
{
    temckrating_install();
}

function temckrating_install() //Install the needed SQl entries.
{
   global $table_prefix, $wpdb;

   $table_name = $table_prefix . "comment_rating";

   $sql = 'DROP TABLE `' . $table_name . '`';  // drop the existing table
   mysql_query($sql);
   $sql = 'CREATE TABLE `' . $table_name . '` (' //Add table
      . ' `ck_comment_id` BIGINT(20) NOT NULL, '
      . ' `ck_ips` text NOT NULL, '
      . ' `ck_rating_up` INT,'
      . ' `ck_rating_down` INT'
      . ' )'
      . ' ENGINE = myisam;';
   mysql_query($sql);
   $sql = 'ALTER TABLE `' . $table_name . '` ADD INDEX (`ck_comment_id`);';  // add index
   mysql_query($sql);

  // echo "comment_rating tables created";

   $ck_result = mysql_query('SELECT comment_ID FROM ' . $table_prefix . 'comments'); //Put all IDs in our new table
   while($ck_row = mysql_fetch_array($ck_result, MYSQL_ASSOC)) //Wee loop
   {
      mysql_query("INSERT INTO $table_name (ck_comment_id, ck_ips, ck_rating_up, ck_rating_down) VALUES ('" . $ck_row['comment_ID'] . "', '', 0, 0)");
   }
}

function temckrating_comment_posted($ck_comment_id) //When comment posted this executes
{
   global $table_prefix, $wpdb;
   $table_name = $table_prefix . "comment_rating";
   mysql_query("INSERT INTO $table_name (ck_comment_id, ck_ips, ck_rating_up, ck_rating_down) VALUES ('" . $ck_comment_id . "', '" . getenv("REMOTE_ADDR") . "', 0, 0)"); //Adds the new comment ID into our made table, with the users IP
}

// cache DB results to prevent multiple access to DB
function temckrating_get_rating($comment_id)
{
   global $ck_cache, $table_prefix, $wpdb;

   // return it if the value is in the cache
   if ($comment_id == $ck_cache['ck_comment_id']) return;

   $table_name = $table_prefix . "comment_rating";
   $ck_sql = "SELECT ck_ips, ck_rating_up, ck_rating_down FROM `$table_name` WHERE ck_comment_id = $comment_id";
   $ck_result = mysql_query($ck_sql);

   $ck_cache['ck_comment_id'] = $comment_id;
   if(!$ck_result) { 
      $ck_cache['ck_ips'] = '';
      $ck_cache['ck_rating_up'] = 0;
      $ck_cache['ck_rating_down'] = 0;
      mysql_query("INSERT INTO $table_name (ck_comment_id, ck_ips, ck_rating_up, ck_rating_down) VALUES ('" . $comment_id . "', '', 0, 0)");
   }
   else if(!$ck_row = mysql_fetch_array($ck_result, MYSQL_ASSOC)) {
      $ck_cache['ck_ips'] = '';
      $ck_cache['ck_rating_up'] = 0;
      $ck_cache['ck_rating_down'] = 0;
      mysql_query("INSERT INTO $table_name (ck_comment_id, ck_ips, ck_rating_up, ck_rating_down) VALUES ('" . $comment_id . "', '', 0, 0)");
   }
   else {
      $ck_cache['ck_ips'] = $ck_row['ck_ips'];
      $ck_cache['ck_rating_up'] = $ck_row['ck_rating_up'];
      $ck_cache['ck_rating_down'] = $ck_row['ck_rating_down'];
   }
}

I try to replace mysql_query with $wpdb->get_results but still get errors

回答1:

mysql_query return a resource. So you get this error by using $wpdb->get_results.

mysql_query() returns TRUE on success or FALSE on error. The returned result resource should be passed to mysql_fetch_array(), and other functions for dealing with result tables, to access the returned data.

You will replace 2 function mysql_fetch_array() and mysql_query instance of $wpdb->get_results. You will define return type -- ARRAY_A, ARRAY_N , OBJECT ,OBJECT_K

global $wpdb;

$ck_sql = $wpdb->get_results("SELECT ck_ips, ck_rating_up, ck_rating_down FROM `$table_name` WHERE ck_comment_id = $comment_id", ARRAY_A);
foreach($ck_sql as $row) {
    echo $row['ck_ips'] . ' ' . $row['ck_rating_up']. ' ' . $row['ck_rating_down '];
}

来源：https://stackoverflow.com/questions/33937047/converting-mysql-query-to-wpdb-get-results