SQL 7.9 游标,row_number() ,update的另一种写法

row_number() over(order by id)      

--------------------------------------------------------------------------  

 

if object_id('[test]') is not null drop table [test]
go
create table [test] (id varchar(4))
insert into [test]
select '0001' union all
select '0001' union all
select '0001' union all
select '0001' union all
select '0001'

DECLARE @I INT
SELECT @I=MIN(ID)-1 FROM test
UPDATE test SET @I=@I+1,id=RIGHT('0000'+LTRIM(@I),4)
SELECT * FROM TEST

 

 

--------------------------------------------------------------------------

DECLARE @I INT 
SELECT @I=MIN(ID) FROM test 
UPDATE test SET id='800-'+RIGHT('0000'+LTRIM(@I-1),4),@I=@I+1
————————————————————————————————

IF OBJECT_ID('test') IS NOT NULL  DROP TABLE test
GO
CREATE TABLE test
(
    id
int
)
GO
INSERT test
SELECT 1 union all
SELECT 1 union all
SELECT 1 union all
SELECT 1 union all
SELECT 1
--查询

declare @i int
set @i=1
declare cur cursor for select id  from test
open cur
fetch cur
while @@fetch_status=0
begin
   
update test set id=@i where current of cur
   
set @i=@i+1
   
fetch cur
end
close cur
deallocate cur

select * from test

这句SQL语句的意思是将一个变量@row_number的值加1,并将其命名为orderNum。在这个语句中,@row_number是一个变量,通过赋值操作符":="来给它赋值。在这个例子中,@row_number的初始值是1,每次执行这个语句,它的值都会自增1。然后,通过AS子句,将其命名为orderNum。这样,每次执行这个语句,都会生成一个新的序号,并以orderNum的形式返回。这个序号通常用于给查询结果排序或标记行。<span class="em">1</span><span class="em">2</span><span class="em">3</span> #### 引用[.reference_title] - *1* [SQL Server Update字段值为ROW_NUMBER()](https://blog.csdn.net/tiemufeng1122/article/details/51202611)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v93^chatsearchT3_2"}}] [.reference_item style="max-width: 33.333333333333336%"] - *2* [sql 游标、存储过程](https://download.csdn.net/download/longchanghua_enshi/7102383)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v93^chatsearchT3_2"}}] [.reference_item style="max-width: 33.333333333333336%"] - *3* [Sql 四大排名函数(ROW_NUMBER、RANK、DENSE_RANK、NTILE)简介](https://blog.csdn.net/qq_27997957/article/details/82532957)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v93^chatsearchT3_2"}}] [.reference_item style="max-width: 33.333333333333336%"] [ .reference_list ]
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