如何通过zerofill来实现mysql组？

Question

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，有没有什么样的MySQL查询到组由ZEROFILL值，我在C1作为RGB代码“0002500034” (r=000/g=250/b=034)所有值，查询后，表示喜欢关于000250034->250034

Answer 1

什么LPAD MySQL函数？ 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; 

您也可以将您的列类型转换为CHAR（9）。

Answer 2

SELECT count(w.c1) AS count 
    , concat(w.c1) AS color 
FROM 
    data w 
GROUP BY 
    w.c1 
    order by w.c1 desc 
LIMIT 
    50000;

只是尝试，它工作正常， 还我会尝试你的版本

编辑： 我的查询：

 
+-----------------+-----------+ 
| Variable_name | Value  | 
+-----------------+-----------+ 
| Last_query_cost | 16.599000 | 
+-----------------+-----------+ 

VS您的

 
+-----------------+----------+ 
| Variable_name | Value | 
+-----------------+----------+ 
| Last_query_cost | 3.599000 | 
+-----------------+----------+