[英]Retrieving data from two tables at once with one table referencing the other
我有两个表,如下所示:
表格1:
ID Code Detail
1 45 Yes
2 46 No
和表2:
Code Detail1 Detail2
45 No 23
22 Yes 34
是否可以从table 2中全部选择,其中detail = YES并且Table 1包含Code并说Yes ?
即查询结果应为 :
Code Detail Detail
45 No 23
22 Yes 34
谢谢。
SQL小提琴: http ://sqlfiddle.com/#!2 / 6f583 / 9
SELECT
Table2.Code,
Table2.Detail1,
Table2.Detail2
FROM
Table1,
Table2
WHERE
Table1.Detail = "Yes" OR
(Table2.Detail1 = "Yes" AND
Table1.Code = Table2.Code)
尽管以上查询似乎为您提供了示例的正确结果集,但我认为以下查询可以更好地满足您的条件:
SQL小提琴: http ://sqlfiddle.com/#!2/6f583/12
SELECT
Table2.Code,
Table2.Detail1,
Table2.Detail2
FROM
Table1,
Table2
WHERE
(Table1.Code = Table2.Code AND
Table1.Detail = "Yes") OR
Table2.Detail1 = "Yes"
GROUP BY
Table1.ID
我不太清楚您的问题,但这将创建您想要的结果表。
select table2.* from table2 left join table1 on table2.code = table1.code where table2.Detail1 = 'Yes' or table1.Detail = 'Yes'
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.