wpdb::query PHP Method

    public function query($query)
    {
        if (!$this->ready) {
            return false;
        }
        /**
         * Filter the database query.
         *
         * Some queries are made before the plugins have been loaded,
         * and thus cannot be filtered with this method.
         *
         * @since 2.1.0
         *
         * @param string $query Database query.
         */
        $query = apply_filters('query', $query);
        $this->flush();
        // Log how the function was called
        $this->func_call = "\$db->query(\"{$query}\")";
        // Keep track of the last query for debug..
        $this->last_query = $query;
        $this->_do_query($query);
        // MySQL server has gone away, try to reconnect
        $mysql_errno = 0;
        if (!empty($this->dbh)) {
            if ($this->use_mysqli) {
                $mysql_errno = mysqli_errno($this->dbh);
            } else {
                $mysql_errno = mysql_errno($this->dbh);
            }
        }
        if (empty($this->dbh) || 2006 == $mysql_errno) {
            if ($this->check_connection()) {
                $this->_do_query($query);
            } else {
                $this->insert_id = 0;
                return false;
            }
        }
        // If there is an error then take note of it..
        if ($this->use_mysqli) {
            $this->last_error = mysqli_error($this->dbh);
        } else {
            $this->last_error = mysql_error($this->dbh);
        }
        if ($this->last_error) {
            // Clear insert_id on a subsequent failed insert.
            if ($this->insert_id && preg_match('/^\\s*(insert|replace)\\s/i', $query)) {
                $this->insert_id = 0;
            }
            $this->print_error();
            return false;
        }
        if (preg_match('/^\\s*(create|alter|truncate|drop)\\s/i', $query)) {
            $return_val = $this->result;
        } elseif (preg_match('/^\\s*(insert|delete|update|replace)\\s/i', $query)) {
            if ($this->use_mysqli) {
                $this->rows_affected = mysqli_affected_rows($this->dbh);
            } else {
                $this->rows_affected = mysql_affected_rows($this->dbh);
            }
            // Take note of the insert_id
            if (preg_match('/^\\s*(insert|replace)\\s/i', $query)) {
                if ($this->use_mysqli) {
                    $this->insert_id = mysqli_insert_id($this->dbh);
                } else {
                    $this->insert_id = mysql_insert_id($this->dbh);
                }
            }
            // Return number of rows affected
            $return_val = $this->rows_affected;
        } else {
            $num_rows = 0;
            if ($this->use_mysqli) {
                while ($row = @mysqli_fetch_object($this->result)) {
                    $this->last_result[$num_rows] = $row;
                    $num_rows++;
                }
            } else {
                while ($row = @mysql_fetch_object($this->result)) {
                    $this->last_result[$num_rows] = $row;
                    $num_rows++;
                }
            }
            // Log number of rows the query returned
            // and return number of rows selected
            $this->num_rows = $num_rows;
            $return_val = $num_rows;
        }
        return $return_val;
    }

 public function query($query, $parameters = array())
 {
     if (!empty($parameters)) {
         $query = str_replace('?', '%s', $query);
         $query = $this->wpdb->prepare($query, $parameters);
     }
     return $this->wpdb->query($query);
 }