Home Database Mysql Tutorial mysql获取group by的总记录行数另类方法

mysql获取group by的总记录行数另类方法

Jun 07, 2016 pm 04:27 PM
mysql method Obtain Number of lines Record

mysql获取group by内部可以获取到某字段的记录分组统计总数,而无法统计出分组的记录数。 mysql的SQL_CALC_FOUND_ROWS 使用 获取查询的行数 在很多分页的程序中都这样写: 代码如下 SELECT COUNT(*) from `table` WHERE ......; 查出符合条件的记录总数 代码

mysql获取group by内部可以获取到某字段的记录分组统计总数,而无法统计出分组的记录数。

mysql的SQL_CALC_FOUND_ROWS 使用 获取查询的行数 在很多分页的程序中都这样写:

代码如下

SELECT COUNT(*) from `table` WHERE ......;

查出符合条件的记录总数

代码如下

SELECT * FROM `table` WHERE ...... limit M,N;

查询当页要显示的数据 这样的语句可以改成:

代码如下

SELECT SQL_CALC_FOUND_ROWS * FROM `table` WHERE ...... limit M, N;

SELECT FOUND_ROWS();

因此可以配合mysql自带的SQL_CALC_FOUND_ROWS和FOUND_ROWS()函数可以实现。

代码如下

SELECT SQL_CALC_FOUND_ROWS t3.id, a,bunch,of,other,stuff FROM t1, t2, t3 WHERE(associate t1,t2,and t3 with each other) GROUPBY t3.id LIMIT 10,20SELECT FOUND_ROWS() as count;

使用以上两个语句即可完成满足group by的总记录行数。

另附:

group by 的简单使用方法:

代码如下

'SELECT column_id,count(*) as count FROM my_table group by column_id';

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