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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