SELECT count(w.c1) AS count
, w.c1 AS color
FROM
data w
GROUP BY
w.c1
ORDER BY
w.id DESC
LIMIT
50000;
我想知道,是否有任何类型的 mysql 查询可以按零填充值分组,我将 c1 中的所有值作为 rgb 代码 ' 0002500034
' (r=000/g=250/b=034)
,查询后它显示为000250034->250034
LPAD MySQL 函数呢?LPAD(str, len, padstr)
SELECT count(w.c1) AS count
, LPAD(w.c1, 9, '0') AS color
FROM
data w
GROUP BY
w.c1
ORDER BY
w.id DESC
LIMIT
50000;
您也可以将列类型转换为 CHAR(9)。
SELECT count(w.c1) AS COUNT , 连接 (w.c1) AS 颜色从 数据 W分组依据 w.c1 订购者:W.C1 DESC限制 50000;
刚刚尝试过,它工作正常, 我也会尝试你的版本
编辑:我的查询:
+-----------------+-----------+|Variable_name |价值 |+-----------------+-----------+|Last_query_cost |16.599000 |+-----------------+-----------+
与你的
+-----------------+----------+|Variable_name |价值 |+-----------------+----------+|Last_query_cost |3.599000 |+-----------------+----------+