select t1.a,t1.b,t1.c,t2.d,t2.e,t3.g from onetable as t1,two table as t2,threetable as t3 where t1.c=t2.f and t3.h=t2.e;使用视图我估计不会提高效率,要提高效率就要考虑如何优化
select t1.a,t1.b,t1.c,t2.d,t2.e,t3.g from onetable as t1,two table as t2,threetable as t3 where t1.c=t2.f and t3.h=t2.e;使用视图我估计不会提高效率,要提高效率就要考虑如何优化
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