很多时候都会用到多表查询,更新,删除,替换. MYSQL多表联合更新与SQL2000有所不同: 7 q! o x( J' U; K
select a.studnt_sno,b.sno,c.grade from studnt as a inner join depart as b on a.sno=b.sno left join sc as c on b.cno=c.no8 Z3 F! E8 a5 i3 Z: P- L+ n* }, ]
select col1, col2, col..., a.*, b.*,c.* from tableA a, tableB b,tableC c WHERE a.**_id = b.**_id AND b.**_id = c.**_id and a.**_id=c.**_idupdate tableA,tableB set tableA.colB= tableB.colB where tableA.colA= tableB.colA;
% k2 @: k6 G2 N; C 对应的SQL2000更新语句为: update tableA set tableA.colB=tableB.colB from tableA,tableB where tableA.colA=tableB.colA
3 X3 _/ [3 q$ C5 u* ^# R更多的自己去扩展吧.. |