SQL SERVER ->> IDENTITY相關函數

IDENTITY函數 -- 只能用在SELECT INTO語句中，用於在插入數據的時候模擬IDENTITY屬性的作用生成自增長值。

SELECT IDENTITY(int, 1,1) AS ID_Num  
INTO NewTable  
FROM OldTable;  

 

IDENT_INCR 函數 -- 返回表的自動增長值，比如我們希望每次增長1，那這個函數就會返回1.

USE AdventureWorks2012;  
GO  
SELECT TABLE_SCHEMA, TABLE_NAME,   
   IDENT_INCR(TABLE_SCHEMA + '.' + TABLE_NAME) AS IDENT_INCR  
FROM INFORMATION_SCHEMA.TABLES  
WHERE IDENT_INCR(TABLE_SCHEMA + '.' + TABLE_NAME) IS NOT NULL;  

 

IDENT_SEED 函數 -- 自動增長列的初始種子值

USE AdventureWorks2012;  
GO  
SELECT TABLE_SCHEMA, TABLE_NAME,   
   IDENT_SEED(TABLE_SCHEMA + '.' + TABLE_NAME) AS IDENT_SEED  
FROM INFORMATION_SCHEMA.TABLES  
WHERE IDENT_SEED(TABLE_SCHEMA + '.' + TABLE_NAME) IS NOT NULL;  
GO  

 

IDENT_CURRENT -- 表的IDENTITY列的當前自動增長值

USE AdventureWorks2012;  
GO  
SELECT TABLE_SCHEMA, TABLE_NAME,   
   IDENT_CURRENT (TABLE_SCHEMA + '.' + TABLE_NAME) AS IDENT_SEED  
FROM INFORMATION_SCHEMA.TABLES  
WHERE IDENT_CURRENT (TABLE_SCHEMA + '.' + TABLE_NAME) IS NOT NULL;  
GO  

 

 

SCOPE_IDENTITY() -- 當前模塊內（存儲過程）生成的最大自動增長值

 

@@IDENTITY -- 當前會話內生成的最大自動增長值