问题不好描述，不好意思
假如A表如下：
x y z
1 23 43 87
2 45 65 76
3 25 65 87
B表如下：
x k
1 23 [y]/[z]
2 45 [z]
3 25 [y]*[z]
如果要查询k的值，该怎么写T-SQL语句啊，如果记录很多，不可能一个个去算呀！
------解决方案--------------------
- SQL code
declare @A table (id int,x int,y int,z int)insert into @Aselect 1,23,43,87 union allselect 2,45,65,76 union allselect 3,25,65,87declare @B table (id int,x int,k varchar(7))insert into @Bselect 1,23,'[y]/[z]' union allselect 2,45,'[z]' union allselect 3,25,'[y]*[z]'select id,x,k= case when k='[y]/[z]' then (select y*1.00/z from @A where x=a.x) when k='[z]' then (select z from @A where x=a.x) when k='[y]*[z]' then (select y*z from @A where x=a.x) when k='[y]' then (select y from @A where x=a.x) when k='[y]+[z]' then (select y+z from @A where x=a.x) when k='[y]-[z]' then (select y-z from @A where x=a.x) endfrom @B a/*id x k----------- ----------- ---------------------------------------1 23 0.49425287356322 45 76.00000000000003 25 5655.0000000000000*/