Question

我想要的是向DB发送请求：

1计算所有行
2返回10行

SELECT count( * ) AS 'total'
FROM stuff
WHERE usr = '65'
LIMIT 10

所以它应该返回10个结果PLUS'total'和所有行的数量。到目前为止，它仅返回计算的行数....

Answer 1

你需要将两个问题分开，然后重新组合它们：

SELECT s.col1, s.col2, s.col3, x.total
FROM `stuff` s
CROSS JOIN 
(
   SELECT count(*) AS total
   FROM `stuff`
   WHERE `usr` = '65'
) x
WHERE s.`usr` = '65'
LIMIT 10;

Fiddle here 像SqlServer和Oracle这样的RDBM允许CTE，它允许你干掉重复的select ... where。 MySql here

中的一些选项

Answer 2

-- count records first
SET @total = (
    SELECT count( * ) AS 'total'
    FROM `stuff`
    WHERE `usr` = '65'
);

-- then, select your ten records and include the total from previous operation
SELECT *, @total
FROM `stuff`
WHERE `usr` = '65'
LIMIT 10

Answer 3

如果您想要计算所有行并将结果限制为10，那么您可以通过以下方式执行此操作

SELECT SQL_CALC_FOUND_ROWS * FROM `stuff` WHERE `usr` = '65' LIMIT 10 
SELECT FOUND_ROWS();

SELECT COUNT所有行并返回10 +和总计数

3 个答案: