T-SQL存储过程：获取父级类别图片

如果当前类别无图片，则获取父级图片，直到找到图片

CREATE   PROCEDURE  w_Category_GetImg
@PCID   int
AS
DECLARE
     @Cache_PCID   int ,
     @ImgCount   int
BEGIN
     SET   @Cache_PCID = @PCID ;
     SET   @ImgCount = ( SELECT   COUNT ( * )  FROM  w_CategoryPhotos  WHERE  PCID = @Cache_PCID )
     IF ( @ImgCount > 0 )
     BEGIN
         SELECT   *   FROM  w_CategoryPhotos  WHERE  PCID = @Cache_PCID
     END
     ELSE
     BEGIN
     WHILE   @ImgCount = 0
         BEGIN
             SET   @Cache_PCID = ( SELECT  ParentID  FROM  w_ProductCategorys  WHERE  PCID = @Cache_PCID );
             SET   @ImgCount = ( SELECT   COUNT ( * )  FROM  w_CategoryPhotos  WHERE  PCID = @Cache_PCID );
             IF ( @ImgCount = 1 )
             BEGIN
                 SELECT   *   FROM  w_CategoryPhotos  WHERE  PCID = @Cache_PCID
                 BREAK ;
             END
         END
     END
END