问一个SQL语句的写法,谢谢

Question

CREATE PROCEDURE test(
@FCurPosAreaCode varchar(6),
)
AS
exec('
select * from testable where FCurPosAreaCode like  ''%'+@FCurPosAreaCode+'%''
')go弥足珍贵的1分，给我

Answer 1

CREATE PROCEDURE test(
@FCurPosAreaCode varchar(6)
)
AS
exec('
select * from testable where FCurPosAreaCode like  ''%'+@FCurPosAreaCode+'%''
')go

Answer 2

CREATE PROCEDURE test(
@FCurPosAreaCode varchar(6)
)
AS
select * from testable where FCurPosAreaCode like  '%'+@FCurPosAreaCode+'%'
go

Answer 3

为什么要加exec呀，什么时间要加呀？