Sql 如何使用记录按id匹配的另一个表中的值更新表中的所有记录?
假设我有两张桌子:Sql 如何使用记录按id匹配的另一个表中的值更新表中的所有记录?,sql,oracle,batch-updates,Sql,Oracle,Batch Updates,假设我有两张桌子: USER +------+------+-------------------+ | ID | NAME | CREATED_TIMESTAMP | +------+------+-------------------+ | 1 | N1 | Null | +------+------+-------------------+ | 2 | N2 | Null | <--------- accep
USER
+------+------+-------------------+
| ID | NAME | CREATED_TIMESTAMP |
+------+------+-------------------+
| 1 | N1 | Null |
+------+------+-------------------+
| 2 | N2 | Null | <--------- acceptor of reference-value
+------+------+-------------------+ \
| ... | ... | ... | \
+------+------+-------------------+ \
\
REFERENCE_CREATED_TIMESTAMPS \
+-------------+----+-------------------+ these records match
| TABLE_NAME | ID |CREATED_TIMESTAMP | /
+-------------+----+-------------------+ /
| USER | 1 | 12.03.12 17:20:40 | /
+-------------+----+-------------------+ /
| USER | 2 | 14.03.12 10:12:54 | <--- reference-value
+-------------+----+-------------------+
| FOO_TABLE | 1 | 17.05.12 08:10:01 |
+-------------+----+-------------------+
| ... | ...| ... |
+-------------+----+-------------------+
用户
+------+------+-------------------+
|ID |名称|创建|时间戳|
+------+------+-------------------+
|1 | N1 |空|
+------+------+-------------------+
|2 | N2 | Null |像这样试试
Update UserTable Set CREATED_TIMESTAMP=
(Select Min(CREATED_TIMESTAMP) from REFERENCE_CREATED_TIMESTAMPS where
REFERENCE_CREATED_TIMESTAMPS.Id=UserTable.Id and Table_Name='User')
大概是这样的:
update USER u, REFERENCE_CREATED_TIMESTAMPS r
set u.CREATED_TIMESTAMP = b.CREATED_TIMESTAMP
where u.ID = r.ID AND r.TABLE_NAME = 'USER'
AND u.ID = 2;
在中有很多很好的更新查询示例,但我认为@Amit适合您的具体情况。虽然在MySQL中可以使用,但多表更新不是标准的SQL,我认为在Oracle中不适用。
update "User"
set CREATED_TIMESTAMP =
(
select rct.CREATED_TIMESTAMP
from REFERENCE_CREATED_TIMESTAMPS rct
where rct.ID = "User".ID
and rct.TABLE_NAME = 'USER'
);