CREATE PROC p_ToIDENTITY
@TableName sysname, --要處理的表名
@FieldName sysname, --要轉換的列名,必須是整型數據字段
@increment int=1    --標識值的增量
AS
IF ISNULL(OBJECTPROPERTY(OBJECT_ID(@TableName),N'IsUserTable'),0)=0
BEGIN
	RAISERROR('"%s" 必須是當前數據庫中已經存在的用戶表',12,16,@TableName)
	RETURN
END

--標識列轉換處理檢查
DECLARE @s1 nvarchar(1000),@s2 nvarchar(4000),@bkTableName sysname
SELECT @s2='',@bkTableName=CAST(NEWID() as char(36)),
	@s1=CASE
		WHEN c.status=0x80 
		THEN N'表"%s"中已經有標識列'+QUOTENAME(c.name,N'"')
			+N',列"%s"不能再被轉換成標識列'
		WHEN t.name LIKE '%int' 
		THEN N','+QUOTENAME(c.name)
			+N'=IDENTITY('+QUOTENAME(t.name)
			+N',1,'+CAST(@increment as varchar)+N')'
		WHEN c.scale=0 AND t.name IN(N'decimal',N'numeric') 
		THEN N','+QUOTENAME(c.name)
			+N'=IDENTITY('+QUOTENAME(t.name)
			+N'('+CAST(c.prec as varchar)+N')'
			+N',1,'+CAST(@increment as varchar)+N')'
		ELSE N'表"%s"中的列"%s"定義"'+QUOTENAME(t.name)
			+CASE WHEN c.scale>0 
				THEN N'('+CAST(c.prec as varchar)
					+N','+CAST(c.scale as varchar)+N')'
				ELSE N'' END
			+N'無效，不能轉換為標識列'
		END
FROM sysobjects o,syscolumns c,systypes t
WHERE o.name=@TableName
	AND o.id=c.id
	AND c.xusertype=t.xusertype
	AND(c.name=@FieldName OR c.status=0x80)
IF @@ROWCOUNT=0
BEGIN
	RAISERROR(N'表 "%s" 中無列 "%s"',12,16,@TableName,@FieldName)
	RETURN
END
IF LEFT(@s1,1)<>','
BEGIN
	RAISERROR(@s1,12,16,@TableName,@FieldName)
	RETURN
END

--生成要處理的列
SELECT @s2=@s2+N','+QUOTENAME(c.name)
FROM sysobjects o,syscolumns c
WHERE o.name=@TableName
	AND o.id=c.id
ORDER BY c.colid
SELECT @s1=REPLACE(@s2+N',',N','+QUOTENAME(@FieldName)+N',',@s1+N','),
	@s1=SUBSTRING(@s1,2,LEN(@s1)-2),
	@s2=STUFF(@s2,1,1,N'')

--修改原表名
EXEC sp_rename @TableName,@bkTableName

--轉換為標識列處理
SELECT @TableName=QUOTENAME(@TableName),
	@bkTableName=QUOTENAME(@bkTableName)
EXEC('
SELECT '+@s1+' INTO '+@TableName+N' 
FROM '+@bkTableName+' WHERE 1=0
SET IDENTITY_INSERT '+@TableName+N' ON
INSERT '+@TableName+N'('+@s2+N')
SELECT '+@s2+N' FROM '+@bkTableName+N'
SET IDENTITY_INSERT '+@TableName+N' OFF
DROP TABLE '+@bkTableName)