在你的版本中，下面这行是错误的:

WHILE (@i <= (SELECT MAX(idx) FROM @Practitioner))

(没有@)

也许可以改变您的命名约定，使表更加不同。

假设列practictionerid是唯一的，那么您可以使用下面的循环

DECLARE @PractitionerId int = 0
WHILE(1 = 1)
BEGIN
  SELECT @PractitionerId = MIN(PractitionerId)
  FROM dbo.Practitioner WHERE PractitionerId > @PractitionerId
  IF @PractitionerId IS NULL BREAK
  SELECT @PractitionerId
END

我想说，除了列idx在你选择的表中不存在之外，一切都可能正常。也许你想从@从业者中选择:

WHILE (@i <= (SELECT MAX(idx) FROM @Practitioner))

因为在上面的代码中是这样定义的:

DECLARE @Practitioner TABLE (
    idx smallint Primary Key IDENTITY(1,1)
    , PractitionerId int
)

您的select count和select max应该来自您的表变量，而不是实际的表

DECLARE @i int
DECLARE @PractitionerId int
DECLARE @numrows int
DECLARE @Practitioner TABLE (
    idx smallint Primary Key IDENTITY(1,1)
    , PractitionerId int
)

INSERT @Practitioner
SELECT distinct PractitionerId FROM Practitioner

SET @i = 1
SET @numrows = (SELECT COUNT(*) FROM @Practitioner)
IF @numrows > 0
    WHILE (@i <= (SELECT MAX(idx) FROM @Practitioner))
    BEGIN

        SET @PractitionerId = (SELECT PractitionerId FROM @Practitioner WHERE idx = @i)

        --Do something with Id here
        PRINT @PractitionerId

        SET @i = @i + 1
    END

在你的版本中，下面这行是错误的:

WHILE (@i <= (SELECT MAX(idx) FROM @Practitioner))

(没有@)

也许可以改变您的命名约定，使表更加不同。

这通常(几乎总是)比游标执行得更好，而且更简单:

DECLARE @PractitionerList TABLE(PracticionerID INT)
DECLARE @PracticionerID INT
    
INSERT @PractitionerList(PracticionerID)
SELECT PracticionerID
FROM Practitioner
    
WHILE(1 = 1)
BEGIN
            
    SET @PracticionerID = NULL
    SELECT TOP(1) @PracticionerID = PracticionerID
    FROM @PractitionerList
    
    IF @PracticionerID IS NULL
        BREAK
            
    PRINT 'DO STUFF'
    
    DELETE TOP(1) FROM @PractitionerList
    
END