这个问题在这里已有答案:
对不起,如果这是一个愚蠢的问题。我可以在ORDER BY
函数中命令我的列,我可以使用LIMIT
函数,但它只给我最高值,但我需要每个最高值限制。
所以我的虚拟表在这里:
Col-a col-b
A 1001
B 1000
B 999
C 998
A 997
C 996
A 995
A 994
A 993
A 992
B 991
C 990
我的期望是(LIMIT 3;)
col_a col_b col_a col_b col_c col_d col_e col_f
A 1001 A 1001 B 1000 C 998
B 1000 A 997 B 999 C 996
B 999 A 995 B 991 C 990
C 998 or
A 997
C 996
A 995
B 991
C 990
我使用FIELD()
但不幸的是我无法管理。我们如何订购特定的电话。
ORDER BY函数顺序所有值,但我需要将每个值取一个特定的数字。当我使用LIMIT
函数时只切顶值问题是如何在“1列”中命令每个不同的值
编辑:我试过了
SELECT col_a,col_b FROM my_table
order BY FIELD(col_b, 'A','B','C') limit 100;
可能有一个更有效的方法,但这可能会让你到达你想去的地方:
SELECT group_a.col_a AS col_a
,group_a.col_b AS col_b
,group_b.col_a AS col_c
,group_b.col_b AS col_d
,group_c.col_a AS col_e
,group_c.col_b AS col_f
FROM (SELECT col_a, col_b FROM my_table WHERE col_a = 'A' ORDER BY col_b DESC LIMIT 100) as group_a,
(SELECT col_a, col_b FROM my_table WHERE col_a = 'B' ORDER BY col_b DESC LIMIT 100) as group_b,
(SELECT col_a, col_b FROM my_table WHERE col_a = 'C' ORDER BY col_b DESC LIMIT 100) as group_c
尽管采用了不同的格式,但为您提供所需的内容。请检查并告诉我这是否适合您
选择COL-A,MIN(COL-B),导联(MIN(COL-B),1)(按MIN(COL-B)排序),导联(MIN(COL-B),2)结束(按顺序排列)来自audit.latest_job_instance的MIN(COL-B))其中COL-B不为空GROUP BY COL-A