1. 简单一点地写
select * from table1
join table2 on (table1.f3 = table2.f3) and (table1.f4=table2.f4)
where (f1 =a) and (f2 =b)2. select * from table1,table2
where (table1.f3 = table2.f3) and (table1.f4=table2.f4) and (f1 =a) and (f2 =b)
select * from table1
join table2 on (table1.f3 = table2.f3) and (table1.f4=table2.f4)
where (f1 =a) and (f2 =b)2. select * from table1,table2
where (table1.f3 = table2.f3) and (table1.f4=table2.f4) and (f1 =a) and (f2 =b)
解决方案 »
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