select * from orders where 1=1 and orderid > 2000
select * from orders where orderid > 2000 and 1=1
在SQLServer分析器中,两条语句的效率一样!
select * from orders where 1=2 or orderid > 2000
select * from orders where orderid > 2000 or 1=2
也是一样
...全文
792打赏收藏
关系SQL查询的效率问题?
select * from orders where 1=1 and orderid > 2000 select * from orders where orderid > 2000 and 1=1 在SQLServer分析器中,两条语句的效率一样! select * from orders where 1=2 or orderid > 2000 select * from orders where orderid > 2000 or 1=2 也是一样