Question

当我尝试在触发器中使用多个分隔的ifs条件来测试字段是否不同于空值时，尝试计算表中的行数时遇到问题。

我试图将if从选择函数中删除，但是它可以工作，但是我无法在所有情况下都这样做，所以不会对其进行优化。

UPDATE max_tare
SET max_row = (
SELECT COUNT(*)
FROM history 
IF(NEW.client != '') THEN
WHERE nom LIKE CONCAT('%', NEW.client, '%') END IF;

IF(NEW.commune != '') THEN
WHERE commune LIKE CONCAT('%', NEW.commune, '%') END IF;

IF(NEW.type != '') THEN
WHERE type LIKE CONCAT('%', NEW.type, '%') END IF;

IF(NEW.matricule != '') THEN
WHERE mat LIKE CONCAT('%', NEW.matricule, '%') END IF;

IF(NEW.tare != '') THEN
WHERE tare LIKE CONCAT('%', NEW.tare, '%') END IF;

WHERE cancled = 0), 
    max_tare =
    (SELECT SUM(tare)
     FROM history
     WHERE cancled = 0) WHERE id = 1;

END

在php查询中，我很容易得到行号，但是当我尝试触发触发器时，出现错误提示：

MySQL回答：＃1064-'IF'（new.client！=''）附近的语法错误其中的名称类似于CONCAT（'％'，NEW.client，'％'）END IF;

我将为在codeigniter框架下使用的php代码提供完美的支持，

$this->db->select("*");

$this->db->from('history');

if ($query[1] != '') {
    $this->db->like('nom', $query[1]);
                }
if ($query[2] != '') {
    $this->db->like('commune', $query[2]);
                }
if ($query[3] != '') {
    $this->db->like('type', $query[3]);
                }
if ($query[4] != '') {
    $this->db->like('mat', $query[4]);
                }
if ($query[10] != '') {
    $this->db->like('rfid', $query[10]);
                }
if ($query[5] != '') {
    $this->db->like('tare', $query[5]);
                }
if ($query[6] != '') {
    $this->db->where('date >', $query[6]);
                }
if ($query[7] != '') {
    $this->db->where('date <', $query[7]);
                }
if ($query[11] != '') {
    $this->db->where('time_plode >', $query[11]);
                }
if ($query[12] != '') {
    $this->db->where('time_plode <', $query[12]);
                }
$this->db->where('cancled', 0);
return $this->db->count_all_results();

此代码将返回行数，在php下工作正常，但我想在触发器而不是php查询中使用它。

希望我更清楚

我会尝试举一个例子：

+----+--------+---------+------+--------------+------+
|                     temp_fetch                     |
+----+--------+---------+------+--------------+------+
| id | client | commune | type | matricule    | tare |
+----+--------+---------+------+--------------+------+
| 1  | EPIC   |         |      |              |      |
+----+--------+---------+------+--------------+------+

这是我触发的表，当我更新它时将激活它，让我们假设它已被更新为这种情况现在，我将尝试过滤我的结果以对其进行计数

+----+-------------+---------+--------+--------------+-------+---------+---------+
|                                      history                                   |
+----+-------------+---------+--------+--------------+-------+---------+---------+
| id | nom         | commune | type   | mat          | tare  | rfid    | cancled |
+----+-------------+---------+--------+--------------+-------+---------+---------+
| 1  | EPIC paris  | france  | white  | 01248-816-16 | 7600  | ABCF44C | 0       |
+----+-------------+---------+--------+--------------+-------+---------+---------+
| 2  | EPIC london | UK      | white  | 06854-315-16 | 5233  | A8CG27C | 1       |
+----+-------------+---------+--------+--------------+-------+---------+---------+
| 3  | NET barça   | ESP     | red    | 03254-615-16 | 8900  | HBC54AC | 1       |
+----+-------------+---------+--------+--------------+-------+---------+---------+
| 4  | NET Dubai   | arab    | blue   | 35251-117-16 | 11200 | HDK7BV5 | 0       |
+----+-------------+---------+--------+--------------+-------+---------+---------+
| 5  | EPIC roma   | ita     | red    | 36524-618-16 | 7300  | NBL53DC | 0       |
+----+-------------+---------+--------+--------------+-------+---------+---------+
| 6  | SNC beta    | alpha   | green  | 69358-117-16 | 5400  | JDLF8ND | 1       |
+----+-------------+---------+--------+--------------+-------+---------+---------+
| 7  | EPIC tokyo  | japan   | yellow | 46258-712-16 | 8700  | K5ND55D | 1       |
+----+-------------+---------+--------+--------------+-------+---------+---------+
| 8  | SARL Fit    | body    | black  | 69531-614-16 | 9600  | AIES5HJ | 0       |
+----+-------------+---------+--------+--------------+-------+---------+---------+

这是我的表，我想计算与数组表（第一个）匹配的行数所以我想要的结果在表max_tare中：

+----------------------------+
|          max_tare          |
+----------------------------+
| id |  max_row   | max_tare |
+----+------------+----------+
| 1  |     2      | 14900    |
+----+------------+----------+

计算了两行分别为nom like epic和where cancled = 0的行希望现在随着我添加简单数据变得清晰

当我尝试Danblack的解决方案时

UPDATE max_tare
SET max_row =
  (SELECT COUNT(*)
   FROM history
   WHERE nom LIKE CONCAT('%', NEW.client, '%')
     AND commune LIKE CONCAT('%', NEW.commune, '%')
     AND TYPE LIKE CONCAT('%', NEW.type, '%')
     AND mat LIKE CONCAT('%', NEW.matricule, '%')
     AND tare LIKE CONCAT('%', NEW.tare, '%')
     AND cancled = 0),
    max_tare =
  (SELECT SUM(tare)
   FROM history
   WHERE cancled = 0)
WHERE id = 1;

我不明白：

+----------------------------+
|          max_tare          |
+----------------------------+
| id |  max_row   | max_tare |
+----+------------+----------+
| 1  |     0      | 14900    |
+----+------------+----------+

这不是我想要的，此解决方案的问题是它在我的表中搜索可以为空的任何数据。

提前感谢您的帮助

Answer 1

首先，有一个IF函数和一个IF语句。它们看起来不同，并且与SQL语法的不同部分相关。

通过不考虑if语句中的空字符串而只使用以下内容，是否可以简化此操作？

UPDATE max_tare
SET max_row =
  (SELECT COUNT(*)
   FROM history
   WHERE nom LIKE CONCAT('%', NEW.client, '%')
     AND commune LIKE CONCAT('%', NEW.commune, '%')
     AND TYPE LIKE CONCAT('%', NEW.type, '%')
     AND mat LIKE CONCAT('%', NEW.matricule, '%')
     AND tare LIKE CONCAT('%', NEW.tare, '%')
     AND cancled = 0),
    max_tare =
  (SELECT SUM(tare)
   FROM history
   WHERE cancled = 0)
WHERE id = 1;

毕竟'%%'作为模式都匹配。

触发器中用于不同条件选择的多个IF

1 个答案: