SQL Server 存储过程自定义生成ID号

 IF EXISTS(SELECT TOP 1 * FROM sys.tables WHERE name=N'EmployeeNo_Identity')
     DROP TABLE EmployeeNo_Identity
 GO

 CREATE TABLE EmployeeNo_Identity(
     ID BIGINT NOT NULL IDENTITY(1000000,1) PRIMARY KEY,
     CreateDate DATETIME DEFAULT(GETDATE())
 )

 IF EXISTS(SELECT TOP 1 * FROM SYS.procedures WHERE name=N'proc_Build_Employee_ID')
     DROP PROC proc_Build_Employee_ID
 GO

 CREATE PROC proc_Build_Employee_ID
     @prefix NCHAR(1),
     @result nvarchar(8) OUT
 AS
 BEGIN
     DECLARE @id BIGINT
     INSERT INTO EmployeeNo_Identity(CreateDate) VALUES(GETDATE())
     SELECT @id=MAX(ID) FROM EmployeeNo_Identity NOLOCK
     DELETE EmployeeNo_Identity
     SET @result=CAST( @prefix+CONVERT(NVARCHAR(7),@id) AS NVARCHAR(8))
 END
 GO

 /** 调用 **/
 DECLARE @result NVARCHAR(8)
 EXEC    [dbo].[proc_Build_Employee_ID]
         @prefix = N'E',
         @result=@result OUT
 SELECT    @result