表结构
A:
CREATE TABLE A (FATHER_ID INT identity(1,1),KH VARCHAR(50),JJ VARCHAR(50),XJ FLOAT,CPMCH VARCHAR(50),CPBH VARCHAR(50),KHDDH VARCHAR(50))
B:
create table B(father_id int identity(1,1),kh varchar(50),jj varchar(50),htbh varchar(50))
----------------要求:
先SQL:select* from A where kh+jj not in(select kh+jj from B)
执行效率太低!请解答!
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