MySql从多个表中获取数据,结果来自一个select
我有一张这样的桌子“移动”MySql从多个表中获取数据,结果来自一个select,mysql,select,multi-table,Mysql,Select,Multi Table,我有一张这样的桌子“移动” ---------------------------------- | id | ... | ... | tab | idTab | ---------------------------------- | 1 | ... | ... | bike | 14 | | 2 | ... | ... | car | 57 | | 3 | ... | ... | car | 23 | | 4 | ... | ... | bike |
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| id | ... | ... | tab | idTab |
----------------------------------
| 1 | ... | ... | bike | 14 |
| 2 | ... | ... | car | 57 |
| 3 | ... | ... | car | 23 |
| 4 | ... | ... | bike | 43 |
| 5 | ... | ... | boat | 20 |
| .. | ... | ... | ... | .... |
----------------------------------
--------------------------------------------------------------
| id | ... | ... | tab | idTab | code | name | matr | ... |
--------------------------------------------------------------
| 1 | ... | ... | bike | 14 | AAA | MARIO | 111 | ... |
| 2 | ... | ... | car | 57 | 2A2 | FRANK | MSS | ... |
| 3 | ... | ... | car | 23 | 123 | JACK | WER | ... |
| 4 | ... | ... | bike | 43 | A1C | JOHN | EEE | ... |
| 5 | ... | ... | boat | 20 | UJN | PETER | WSX | ... |
| .. | ... | ... | ... | .... | ... | .... | .... | ... |
--------------------------------------------------------------
“自行车”标签
标签“汽车”
标签“船”
我希望在单个查询中包含“move”的所有数据以及“move”中包含的每个表的数据,并使用特定的idTab
结果是这样的
----------------------------------
| id | ... | ... | tab | idTab |
----------------------------------
| 1 | ... | ... | bike | 14 |
| 2 | ... | ... | car | 57 |
| 3 | ... | ... | car | 23 |
| 4 | ... | ... | bike | 43 |
| 5 | ... | ... | boat | 20 |
| .. | ... | ... | ... | .... |
----------------------------------
--------------------------------------------------------------
| id | ... | ... | tab | idTab | code | name | matr | ... |
--------------------------------------------------------------
| 1 | ... | ... | bike | 14 | AAA | MARIO | 111 | ... |
| 2 | ... | ... | car | 57 | 2A2 | FRANK | MSS | ... |
| 3 | ... | ... | car | 23 | 123 | JACK | WER | ... |
| 4 | ... | ... | bike | 43 | A1C | JOHN | EEE | ... |
| 5 | ... | ... | boat | 20 | UJN | PETER | WSX | ... |
| .. | ... | ... | ... | .... | ... | .... | .... | ... |
--------------------------------------------------------------
我不知道实际上我是否有一个移动中的特定表。
我可以这样提问
SELECT * FROM move WHERE id>0
然后是一个有
SELECT * FROM move["tab"] WHERE id=move["idTab"]
但是工作很辛苦,因为桌子移动很长
我试着用这个,但(显然)不起作用
SELECT M.*, T.* FROM move as M, M.tab as T WHERE M.id>0 AND M.idTab=T.id
您的数据库设计并不理想,我认为您不应该为每种类型的车辆设置单独的表。也就是说,如果您使用
联合将三个表合并为一个表,那么单个连接可以产生您想要的结果
SELECT t1.*, t2.*
FROM move t1
INNER JOIN
(
SELECT id, code, name, matr, 'bike' AS tab
FROM bike
UNION ALL
SELECT id, code, name, matr, 'car'
FROM car
SELECT id, code, name, matr, 'boat'
FROM boat
) t2
ON t1.idTab = t2.id AND
t1.tab = t2.tab
我为表的类型添加了一个计算列,假设相同的id
可能出现在多个车辆表中。为什么不将所有公共列存储在一个表中table@Strawberry因为这样用户就不会有任何工作要做了,我们显然不希望这样:-)谢谢。。。我有更多的表格,其中包含更多的车辆信息,还有一个类似于将这些信息与一般信息连接起来的表格。@FrancescoG。。。你的问题是?这只是为了解释,因为我的数据库就是这样设计的。只是想知道,如果(例如)我没有在“移动”一个项目“船”,查询会工作吗?
Select 'bike' vehicle,column1,.... from bike
Union
Select 'boat',column1,... from boat
Union...
SELECT t1.*, t2.*
FROM move t1
INNER JOIN
(
SELECT id, code, name, matr, 'bike' AS tab
FROM bike
UNION ALL
SELECT id, code, name, matr, 'car'
FROM car
SELECT id, code, name, matr, 'boat'
FROM boat
) t2
ON t1.idTab = t2.id AND
t1.tab = t2.tab