COUNT与LIMIT在mysql查询 [英] COUNT with LIMIT in mysql query

问题描述

我需要获取总量的行使用LIMIT与我的查询，以避免两次查询。
是可能吗？

i need to get total amount of rows when using LIMIT with my query to avoid twice querying. is it possible?

推荐答案

使用 FOUND_ROWS（） ：

对于具有LIMIT子句的SELECT，返回的行数没有LIMIT子句

For a SELECT with a LIMIT clause, the number of rows that would be returned were there no LIMIT clause

在SELECT查询之后，需要 CALC_FOUND_ROWS 关键字。示例从手册：

use the statement right after your SELECT query, which needs the CALC_FOUND_ROWS keyword. Example from the manual:

SELECT SQL_CALC_FOUND_ROWS * FROM tbl_name
WHERE id > 100 LIMIT 10;

请注意，这会给数据库带来额外的压力，因为它必须找出完整的结果集每次。只有在需要时才使用 SQL_CALC_FOUND_ROWS 。

Note that this puts additional strain on the database, because it has to find out the size of the full result set every time. Use SQL_CALC_FOUND_ROWS only when you need it.

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