摘要： use master;set nocount on;if DB_ID('Performance') is nullcreate database Performance;gouse Performance;goset nocount on;if OBJECT_ID('dbo.Nums', 'U') is not nulldrop table dbo.nums;create table dbo.nums(n int not null primary key );declare @max as int, @rc as int;set @max = 5 阅读全文