php - codeigniter 2.1 でこの SQL クエリを実行する方法

Question

私は codeigniter 2.1 を使用していますが、このコードを実行する必要がある SQL バージョンに関するエラーが表示されます..しかし、その方法

表示されるエラー:

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'SELECT rt.srt_id, rt.pub_id, d.sd_date, CASE WHEN d.sd_doc != '' THEN d' at line 2

SET @i = 0.0; SELECT rt.srt_id, rt.pub_id, d.sd_date, CASE WHEN d.sd_doc != '' THEN d.sd_doc END sd_doc, rt.total_sales, @i + rt.total_sales AS Cumulative_Total, @i:= CASE WHEN d.sd_doc = '' THEN @i + rt.total_sales ELSE 0 END AS Increment FROM d_statistics_report_temp rt INNER JOIN d_statistics_docs d ON rt.pub_id = d.sd_pub AND rt.sal_must_pay_date = d.sd_date ORDER BY rt.pub_id, d.sd_date;

Filename: C:\xampp\htdocs\ebook\system\database\DB_driver.php

Line Number: 330

SQL クエリは次のとおりです。

 $result = $this->db->query(
            "SET @i = 0.0;
           SELECT   rt.srt_id,
                           rt.pub_id,
                           d.sd_date,
                           CASE WHEN d.sd_doc != '' THEN d.sd_doc END sd_doc,
                           rt.total_sales,
                           @i + rt.total_sales AS Cumulative_Total,
                           @i:= CASE WHEN d.sd_doc = '' THEN @i + rt.total_sales ELSE 0 END AS Increment
           FROM d_statistics_report_temp rt
                           INNER JOIN d_statistics_docs d
                                   ON rt.pub_id = d.sd_pub
                                   AND rt.sal_must_pay_date = d.sd_date
           ORDER BY rt.pub_id, d.sd_date; "
        );