使用while循环获取下一条记录

Question

我不允许使用游标或临时表。我只能使用while循环。

表1 - 只读表（不可编辑）

id name 

M01 Raja 
M02 Ravi 
M03 Vijay 
M04 suresh 

查询

Declare @TotRecord int, @CurrRecord Int, @id varchar(10) 

Select @TotRec = COUNT(*) from Table1 
Set @CurrRec = 1 
WHILE (@CurrRec <=@TotRec) 
BEGIN 

--*Here i want to get the id from table, 
--next time i need to get second id. 
--next time i need to get third id. 
--.... 

--1st time i can get the top 1 id by using this below query 
Select top 1 @id = id from table 
--Next time i want to get second id.* 


SET @CurrRec = @CurrRec + 1 
END 

Answer 1

Select id,name,row_number() over (order by id) 'Row' into #temp 
from table 

Select @id = id from #temp where row = @current 

使用临时表来获取下一个ID

Answer 2

使用

SELECT TOP 1 * FROM table WHERE id > @iterator ORDER BY id ASC 

模式

在一个循环

Answer 3

如果ID是序列号（M01，M02，M03，...），那么您可以在使用下列与while循环

SELECT TOP 1 @id = id FROM table WHERE CAST(REPLACE(id,'M','') AS INT) = @CurrRecord 

完整的查询

DECLARE @TotRecord INT, @CurrRecord INT, @id VARCHAR(10) 

SELECT @TotRecord = COUNT(*) FROM Table1 
SET @CurrRecord = 1 
WHILE @CurrRecord <= @TotRecord 
BEGIN 
    -- Get ID 
    SELECT TOP 1 @id = id FROM Table1 WHERE CAST(REPLACE(id,'M','') AS INT) = @CurrRecord 

    -- Do something 

    SET @CurrRecord = @CurrRecord + 1 
END 

Answer 4

您可以使用光标一对一地获取您的查询记录。

例如：

Declare @Col1 INT, 
     @Col2 INT, 
     ... 


DECLARE X CURSOR FOR 
SELECT Col1, col2 , ... 
FROM YourTableName 


OPEN X 
FETCH NEXT FROM X INTO @Col1, @Col2, ... 
WHILE @@FETCH_STATUS=0 BEGIN 
    --your code to do with columns data of your record 
    FETCH NEXT FROM X INTO @Col1, @Col2, ... 
END 
CLOSE X 
DEALLOCATE X 

您还可以使用其中对于你的想法：

DECLARE @Id INT, 
     @OldId INT, 
     @Col1 INT, 
     @Col2 INT 
     ... 

WHILE 1=1 BEGIN 

    SET @OldId = @Id 
    SET @Id = NULL 

    SELECT TOP 1 @Id = Id, 
       @Col1 = Column1, 
       @Col2 = Column2 
    FROM YourTable 
    WHERE (@OldId IS NULL OR Id > @OldId) ORDER BY Id 

    IF @Id IS NULL BREAK 

    -- your Code Here 
END 

Answer 5

DECLARE @TotRecord INT; 
DECLARE @CurrRecord INT; 
DECLARE @id VARCHAR(10); 

SELECT @TotRecord = COUNT(*) from Table1; 
SELECT @CurrRecord = 1; 
SELECT TOP 1 @id = id FROM Table1 ORDER BY id; 
WHILE (@CurrRecord <= @TotRecord) 
BEGIN 
    --Do something... 
    --Get the next id 
    SELECT TOP 1 @id = id FROM Table1 WHERE id > @id ORDER BY id; 
    SELECT @CurrRecord = @CurrRecord + 1; 
END; 

但要注意的是，如果该ID是在表1的独特，这只会工作。

Answer 6

Declare @TotRecord int, @CurrRecord Int, @id varchar(10) 

    Select @TotRec = COUNT(*) from Table1 
    Set @CurrRec = 1 
    WHILE (@CurrRec <=@TotRec) 
    BEGIN 

    select LAST(id) from (SELECT TOP @CurrRec id 
    FROM Table1); 

    //Here you will get the last record, i havent tried this, but iam sure about the logic , hope this one helps 

    SET @CurrRec = @CurrRec + 1 
    END