Question

DECLARE @CityId AS VARCHAR(20) = NULL
DECLARE @CityList AS VARCHAR(20) = '1, 2, 3, 4, 5';

IF (@CityId IS NULL)
    SET @CityId = @CityList;

SELECT *
FROM City
WHERE CityID IN (@CityId)

我有一个列出所有城市的存储过程。但是如果设置了参数，那么它应该只显示有关该城市的特定信息。 City Table中的CityID是bigint。如果CityId保留为null，则会显示错误消息“ 将数据类型varchar转换为bigint时出错。 '

注意：如果我构造以下查询，一切似乎都没问题。

SELECT * FROM City WHERE CityID IN (1, 2, 3, 4, 5)

但如果我继续使用以下查询，则会出错。

SELECT * FROM City WHERE CityID IN ('1, 2, 3, 4, 5')

我想我应该在这种情况下构建int数组，但我不知道该怎么做。有什么建议吗？

Answer 1

您可以使用动态SQL

exec('SELECT * FROM City WHERE CityID IN (' + @CityId + ')')

Answer 2

试试这个：

IF (@CityId IS NULL)
    SET @CityId = ',' + REPLACE(@CityList, ' ', '') + ','; 
ELSE
    SET @CityId = ',' + @CityId + ',';

SELECT * 
FROM City 
WHERE charindex(',' + CAST(CityID as nvarchar(20)) + ',', @CityId) > 0

Answer 3

DECLARE @CityId AS VARCHAR(20) = NULL
DECLARE @CityList AS VARCHAR(20) = '1, 2, 3, 4, 5';

IF (@CityId IS NULL)
    SET @CityId = @CityList;

DECLARE @SQL NVARCHAR(MAX);        

 SET @SQL = N'        
 SELECT *
FROM City
 where  
  1 = 1  
  AND Cityid in ('+@CityId+')    
  ';        


 SELECT @SQL = @SQL + N' ';        


 EXEC Sp_executeSQL         
   @SQL

Answer 4

存储过程

DELIMITER $$
DROP PROCEDURE IF EXISTS `mystoredprocedure`$$
CREATE PROCEDURE `mystoredprocedure`(IN city_id AS VARCHAR(20))
BEGIN
SET @CityId = city_id; 
SET @where_condition = "";
IF (@CityId IS NULL)  THEN 
SET @where_condition  = CONCAT(@where_condition,"1, 2, 3, 4, 5"); 
ELSE
SET @where_condition  = @CityId;
END IF;
SET @query = CONCAT("SELECT * FROM City WHERE CityID IN (",@where_condition,")");
PREPARE stmt FROM @query;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
END$$
DELIMITER ;

致电声明

CALL `mystoredprocedure`(NULL);

OR

CALL `mystoredprocedure`('1,2,3');

SELECT存储过程中的城市

4 个答案: