为什么这段存储过程中没有CREATE，直接用了ALTER

USE [db_House]

GO

/****** Object:  StoredProcedure [dbo].[proc_employee_insert]    Script Date: 2021/3/31 8:50:19 ******/

SET ANSI_NULLS ON

GO

SET QUOTED_IDENTIFIER ON

GO

ALTER  proc [dbo].[proc_employee_insert]

@employee_ID	varchar	(10)=null,

@employee_name	varchar	(20)=null,

@employee_sex   varchar(10)=null,

@employee_birthday datetime,

@employee_phone varchar(20),

@employee_cardID varchar(20),

@employee_address varchar(50),

@gov_id varchar (16),

@employee_study varchar(16),

@employee_basepay numeric



as 

select @employee_ID=Max(employee_ID) from tb_employee

	if(@employee_ID is null)

		set @employee_ID='emp1001'--作动见编号就知道是什么表

	else

		set @employee_ID='emp'+cast(cast(substring(@employee_ID,4,4) as int)+1 as varchar(20))



	insert into tb_employee values(@employee_ID,@employee_name,@employee_sex, 

					@employee_birthday,@employee_phone,@employee_cardID,

					@employee_address,@gov_id,@employee_study,@employee_basepay)

end