MySQL?? ?? ??? ?? ??
??? ?? ??? MySQL ???? ??? ??? ?????.
| 公司名稱 | 操作 | 頁數(shù) |
|---|---|---|
| 公司A | 打印 | 3 |
| 公司A | 打印 | 2 |
| 公司A | 打印 | 3 |
| 公司B | 郵件 | NULL |
| 公司B | 打印 | 2 |
| 公司B | 打印 | 2 |
| 公司B | 打印 | 1 |
| 公司A | 打印 | 3 |
?? ??? MySQL ??? ???? ??? ??? ??? ???? ????.
| 公司名稱 | 郵件 | 打印1頁 | 打印2頁 | 打印3頁 |
|---|---|---|---|---|
| 公司A | 0 | 0 | 1 | 3 |
| 公司B | 1 | 1 | 2 | 0 |
????? ? ??? ? ?? ??? ?? ?? ? ??? ? ??? ???? ???? ???? ?? ???? ?????.
???
MySQL?? ?? ??? ??? ????? CASE ?? ???? ? ?? ?? ??? ???? GROUP BY? ???? ?? ???? ???? ??? ? ????.
??? ??? ?? SQL ?? ??? ????.
SELECT P.`company_name`,
COUNT(
CASE
WHEN P.`action`='EMAIL'
THEN 1
ELSE NULL
END
) AS 'EMAIL',
COUNT(
CASE
WHEN P.`action`='PRINT' AND P.`pagecount` = '1'
THEN P.`pagecount`
ELSE NULL
END
) AS 'PRINT 1 pages',
COUNT(
CASE
WHEN P.`action`='PRINT' AND P.`pagecount` = '2'
THEN P.`pagecount`
ELSE NULL
END
) AS 'PRINT 2 pages',
COUNT(
CASE
WHEN P.`action`='PRINT' AND P.`pagecount` = '3'
THEN P.`pagecount`
ELSE NULL
END
) AS 'PRINT 3 pages'
FROM test_pivot P
GROUP BY P.`company_name`;
? ??? ??? ?? ??? ??? ?????.
????
- ? ?? ??/??? ??? ??? ??? ???? ?? SQL ?? ? ?? CASE ??? ?????.
- ?? ??? ???? ?? ??? ??? ??? ??? ? ????.
? ??? MySQL ??? ???? ?? ??? ??? ???? ??? ??????? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!
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Undress AI Tool
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