SQL 现有列的增量值

Question

我在 sql 服务器中有一个具有以下结构的 table，我想创建一个更新存储过程来设置 seq_num 列的值。

fname	lname	orderid	seq_num
Torrey	Venard	246	376987
Gabey	Tate	247	376988
Germaine	Ferminger	248	376989
Nikita	Sharplin	249	376990
Boyd	Rannigan	250	376991
Claretta	Paoli	251	376992
Barn	Kulver	252	376993
Torrey	Venard	253	376994
Gabey	Tate	254	NULL
Germaine	Ferminger	255	NULL
Nikita	Sharplin	256	NULL
Boyd	Rannigan	257	NULL

总行数约为 20k。理想情况下，我们应该将此列作为自动增量，但我们正在寻找的是用下一个数字填充 NULL，如下所示：

fname	lname	orderid	seq_num
Torrey	Venard	246	376987
Gabey	Tate	247	376988
Germaine	Ferminger	248	376989
Nikita	Sharplin	249	376990
Boyd	Rannigan	250	376991
Claretta	Paoli	251	376992
Barn	Kulver	252	376993
Torrey	Venard	253	376994
Gabey	Tate	254	376995
Germaine	Ferminger	255	376996
Nikita	Sharplin	256	376997
Boyd	Rannigan	257	376998

任何想法建议将不胜感激！

Answer 1

我认为 seq_num 列是整数。所以你可以尝试使用 cursor 如下：

DECLARE @Orderid int 

DECLARE Seq_CURSOR CURSOR FOR 

    Select  Orderid from table1 Where seq_num IS NULL  Order by Orderid

    OPEN Seq_CURSOR
    BEGIN TRY
    FETCH NEXT FROM Seq_CURSOR  INTO @Orderid  

    
    WHILE @@FETCH_STATUS = 0 
        BEGIN
            BEGIN TRAN   
            
           Update table1 set seq_num = (Select Max(seq_num)+1 from table1 )  Where orderId = @Orderid

            FETCH NEXT FROM Seq_CURSOR  INTO @Orderid  
            
            SET CURSOR_CLOSE_ON_COMMIT OFF;
            COMMIT TRAN;
                      
        END
        DEALLOCATE Seq_CURSOR;   
    END TRY 

    BEGIN CATCH 
    PRINT ERROR_MESSAGE()
        ROLLBACK
    END CATCH
CLOSE Seq_CURSOR
DEALLOCATE Seq_CURSOR

SQL 现有列的增量值

SQL Incremental Value for Existing Column

sql

sql-server

stored-procedures