Question

我只是想知道MySQL实际上是如何执行“IN”查询的。

例如，我有一个查询，其中我在IN数组中使用100个参数，如：

SELECT  productName, price  FROM tbl_product WHERE id IN (1,2,3,4,5,6,7,8,9,10,11,......,100) AND status = 'y';

现在，SQL引擎如何执行此查询？

是否会启动任何循环，如

SELECT productName, price FROM tbl_product WHERE id = '1' AND status = 'y';

SELECT productName, price FROM tbl_product WHERE id = '2' AND status = 'y';

SELECT productName, price FROM tbl_product WHERE id = '3' AND status = 'y';

SELECT productName, price FROM tbl_product WHERE id = '4' AND status = 'y';
.........
........
......
SELECT productName, price FROM tbl_product WHERE id = '98' AND status = 'y';

SELECT productName, price FROM tbl_product WHERE id = '99' AND status = 'y';

SELECT productName, price FROM tbl_product WHERE id = '100' AND status = 'y';

OR

只需从

等1个查询中获取

SELECT productName, price FROM tbl_product WHERE (id = '1' OR id = '2' OR id = '3' OR id = '4' OR id = '5' .......... OR id = '99' OR id = '100') AND status = 'y';

MySQL引擎如何执行IN查询？

0 个答案: