尝试在 SQL WHERE IN 语句中使用变量

Question

我正在尝试使用 @List Table 来提供 Where IN 语句。我一直收到错误消息“必须声明标量变量“@List”。

我知道我可以简单地在 WHERE IN 部分使用 select 语句，但我需要从概念上找出这是否可能用于更大的 SQL 语句，我可以'不分享全部。

DECLARE @EarliestDate date Set @EarliestDate = '2020-01-01'

DECLARE @LatestDate date Set @LatestDate = '2020-01-05'

DECLARE @List TABLE(DATAPOINT varchar(20))   


INSERT INTO @List SELECT number1  + CONVERT(varchar(5),number2)  
                                                         
FROM 
                                                         tbl1 
                                                         
INNER JOIN msts tb2 on tbl1.j = tbl2.j and tbl1.s = tbl2.s
                                                        
 INNER JOIN tbl3  on tbl3.r = tbl1.j and tbl3.re = tbl1.s                                                    
                                            
 AND tbl2.date > @EarliestDate
                                                        
 AND tbl2.date < @LatestDate
                                                        

SELECT number3
, number4


FROM table1 ci


WHERE 1=1
AND ci.number1 + CONVERT(varchar(5),ci.number2) IN (**@List**)

Answer 1

要正确使用 in()，您必须指定一个查询，而不仅仅是将您声明并插入数据的 table 变量放入。

示例：

DECLARE @EarliestDate date Set @EarliestDate = '2020-01-01'

DECLARE @LatestDate date Set @LatestDate = '2020-01-05'

DECLARE @List TABLE(DATAPOINT varchar(20))   


INSERT INTO @List SELECT number1  + CONVERT(varchar(5),number2)  
                                                         
FROM 
                                                         tbl1 
                                                         
INNER JOIN msts tb2 on tbl1.j = tbl2.j and tbl1.s = tbl2.s
                                                        
 INNER JOIN tbl3  on tbl3.r = tbl1.j and tbl3.re = tbl1.s                                                    
                                            
 AND tbl2.date > @EarliestDate
                                                        
 AND tbl2.date < @LatestDate
                                                        

SELECT number3
, number4


FROM table1 ci


WHERE 1=1
AND ci.number1 + CONVERT(varchar(5),ci.number2) IN (select DATAPOINT from @List)

Answer 2

为了完整起见，您还可以使用 CTE 解决此问题——有时速度更快。我在这里也使用了连接，因为有时也可以让编译器优化。

DECLARE @EarliestDate date Set @EarliestDate = '2020-01-01';

DECLARE @LatestDate date Set @LatestDate = '2020-01-05';

WITH list AS 
(
  SELECT number1  + CONVERT(varchar(5),number2) as DATAPOINT
  FROM tbl1 
  JOIN msts tb2 on tbl1.j = tbl2.j and tbl1.s = tbl2.s
  JOIN tbl3  on tbl3.r = tbl1.j and tbl3.re = tbl1.s                                                    
        AND tbl2.date > @EarliestDate
        AND tbl2.date < @LatestDate
)                  
SELECT number3, number4
FROM table1 ci
JOIN list on ci.number1 + CONVERT(varchar(5),ci.number2) = DATAPOINT ;

尝试在 SQL WHERE IN 语句中使用变量

Trying to use a variable in a SQL WHERE IN statement

sql-server

tsql

table-variable