|
查看: 1610|回复: 3
|
mysql兩個table,如何select最新ID
[复制链接]
|
|
|
mysql> select * from t1;
+----+------+
| ID | Nm |
| T1 | TTT |
| T2 | TT2 |
+----+------+
mysql> select * from t2;
+----+------+------------+------+
| ID | Nm | Dt | Ei |
| L1 | LL1 | 2008-01-12 | T1 |
| L2 | LL2 | 2008-01-13 | T1 |
| L3 | LL3 | 2008-01-12 | T2 |
| L4 | LL4 | 2008-01-13 | T2 |
+----+------+------------+------+
mysql> select Nm,ID as xx,(select max(Dt) from t2 where Ei=xx) as yy from t1;
+------+----+------------+
| Nm | xx | yy |
| TTT | T1 | 2008-01-13 |
| TT2 | T2 | 2008-01-13 |
+------+----+------------+
如何在以上的table加一個t2.Nm or t2.ID?
| TTT | T1 | 2008-01-13 | LL2 |
| TT2 | T2 | 2008-01-13 | LL4 |
PLS 教教我 THANK YOU |
|
|
|
|
|
|
|
|
|
|

楼主 |
发表于 6-2-2008 09:21 AM
|
显示全部楼层
|
沒人帮帮我................................... |
|
|
|
|
|
|
|
|
|
|
发表于 6-2-2008 04:04 PM
|
显示全部楼层
select tbl.Nm
, tbl.xx
, substring(tbl.yy, 1, locate('*', tbl.yy) - 1) as yy
, substring(tbl.yy, locate('*', tbl.yy) + 1) as t2Nm
from (select Nm
,ID as xx
,(select max(concat(Dt, '*', Nm) from t2 where Ei=xx) as yy
from t1) tbl
| Nm | xx | yy | t2Nm|
| TTT | T1 | 2008-01-13 | LL2 |
| TT2 | T2 | 2008-01-13 | LL4 | |
|
|
|
|
|
|
|
|
|
|
发表于 24-2-2008 11:49 AM
|
显示全部楼层
可以试:
select Nm, ID as xx,
(select max(Dt) from t2 where Ei=xx) as yy,
(select Nm from t2 where Dt=yy limit 1) as t2_Nm,
(select ID from t2 where Dt=yy limit 1) as t2_ID
from t1;
[ 本帖最后由 k-1 于 24-2-2008 11:52 AM 编辑 ] |
|
|
|
|
|
|
|
|
| |
本周最热论坛帖子
|