mysql - 将 "ifs"嵌套在 select-where 中以进行条件动态过滤

Question

最近我创建了一个基于 codeigniter 3-php 和 PHPMyADMIN-mysql 的新网站，我集成的分页比使用 ajax 进行的动态搜索还要多。我的问题是，当我有超过 100 万个 50 万个结果时，查询开始花费大量时间。

对于这个解决方案，我考虑使用触发器。所以我在使用触发器时遇到了一点麻烦，就是当我尝试制作动态过滤器时，我举了一个例子来更好地理解，我想知道存储在另一个动态表中的过滤器对应的行数。

BEGIN
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 

问题是，如果我删除所有 ifs 语句 条件，我的过滤器将无法工作，如果我的过滤器包含空字段，它会将结果破坏为 0，我希望它是否为空字段它不算作过滤的参数。我也尝试过案例陈述，这也没有帮助。

当我运行代码时，我得到的错误是:

MySQL replied: # 1064 - Syntax error near 'IF' (new.client! = '') THEN WHERE name LIKE CONCAT ('%', NEW.client, '%') END IF;

有一个很长的解决方案可以工作，但我不需要，因为我不能将其称为解决方案:
就是把外面的取出来，对得到的每一个case进行select，换句话说:

if (client! = 0 and common == 0 and type == 0 and number == 0 and tare == 0) then
{filter by client only}
otherwise-if (client! = 0 and common! = 0 and type == 0 and number == 0 and tare == 0) then
{filter by client and common only} .... ect

我将尝试举一个例子来使其更清楚:这是我的历史表:

|                                         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       |
+----+-------------+---------+--------+--------------+-------+---------+---------+

我想检索包含 cancled = 0 的行数，并且在其名称中包含 EPIC

所以我的文件管理器数组将是这样的:

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

结果我应该有这样的东西

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

如果它有帮助，我会将我的 php 代码放在那里，该代码可以工作，但加载结果需要太多时间

$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();

Answer 1

您是否正在寻找加入和分组依据？

select f.id,
       count(*) as num_rows,
       sum(tare) as sum_tare
from history h join
     temp_fetch f
     on h.nom like concat('%', f.client, '%') or
        h.commune like concat('%', f.commune, '%')  or 
        h.type like concat('%', f.type, '%') or 
        h.mat like concat('%', f.matricule, '%') or 
        h.tare like concat('%', f.tare, '%')
where f.cancled = 0
group by f.id;