表A
1---------BV
2---------cV
3---------rV
4---------qV表B
1---------V
2---------是null,不是字符串"null"
select distinct(a.id),a.value,b.valuefrom 表A a ,表B bwhere instr(a.value,b.value)>0
1---------BV
2---------cV
3---------rV
4---------qV表B
1---------V
2---------是null,不是字符串"null"
select distinct(a.id),a.value,b.valuefrom 表A a ,表B bwhere instr(a.value,b.value)>0
select distinct(a.id),a.value,b.value from 表A a ,表B b where instr(a.value,ifnull(b.value,''))>0