Question

我正在尝试在sql语句中连接字符串。我正在使用sql server，这就是它的外观；
declare @SchoolID INT ,@Transaction nVarChar(35) ,@Reporting nVarChar(35) ,@SchoolOf nVarChar(35) ,@SchoolYear INT ,@Charter Varchar(25) ,@Value varchar(max)



SET @SchoolID   = 105           -- HS - 65, MS - 66, ES - 67
SET @TransactionTypeCode = ''   -- '', 'D', 'R'
SET @ReportingLEA = '1'
SET @SchoolOfAttendance = '1' -- HS - 1930056, MS - 6061238, ES - 6010862
SET @SchoolYear =295
SET @Charter = 'ALL'
SET @Value = 
            CASE @Charter
                WHEN 'Los Angeles'
                    THEN 'Los Angeles'
                WHEN'San Diego'
                    THEN 'San Diego'
                WHEN 'Fresno'
                    THEN 'Fresno'                           
                WHEN 'ALL'
                    THEN 'Los Angeles' + ',' +'San Diego'+ ','+'Fresno' --trying to concatenate data to show in the clause IN like charter IN ('Los Angeles','San Diego','Fresno')
            END

 print @Value

SET @SchoolID = 105 -- HS - 65, MS - 66, ES - 67 SET @TransactionTypeCode = '' -- '', 'D', 'R' SET @ReportingLEA = '1' SET @SchoolOfAttendance = '1' -- HS - 1930056, MS - 6061238, ES - 6010862 SET @SchoolYear =295 SET @Charter = 'ALL' SET @Value = CASE @Charter WHEN 'Los Angeles' THEN 'Los Angeles' WHEN'San Diego' THEN 'San Diego' WHEN 'Fresno' THEN 'Fresno' WHEN 'ALL' THEN 'Los Angeles' + ',' +'San Diego'+ ','+'Fresno' --trying to concatenate data to show in the clause IN like charter IN ('Los Angeles','San Diego','Fresno') END print @Value

我想要的是，如果用户选择“全部” 然后的价值但是没有用。我相信in子句不支持这种连接如果运行此查询并将变量设置为“ ALL”，那么我将在打印结果中得到此信息： @Value would be: 'Los Angeles' + ',' +'San Diego'+ ','+'Fresno' inside the in clause: AND gsrf.Charter in (@Value) 但是，如果我运行带有此结果的整个脚本（不进行IN分隔），则不会获得任何数据。有什么建议吗？

Answer 1

我不知道您在使用变量做什么，但是我认为您想要的逻辑更像是：

where (Charter = @Charter or @Charter = 'All')

Answer 2

如果不执行动态语句，则不能在SQL的IN选择器中使用逗号分隔的字符串变量。

话虽如此，您可以通过将@Value类型更改为XML，然后查询XML来代替逗号分隔的字符串来实现目标。

因此，例如：

SET @Value = CASE @Charter
    WHEN 'Los Angeles'
        THEN '<cities><city>Los Angeles</city></cities>'
    WHEN'San Diego'
        THEN '<cities><city>San Diego</city></cities>'
    WHEN 'Fresno'
        THEN '<cities><city>Fresno</city></cities>'                           
    WHEN 'ALL'
        THEN '<cities><city>Los Angeles</city><city>San Diego</city><city>Fresno</city></cities>'
END

然后将@Value与IN选择器一起使用：

...AND gsrf.Charter IN (

    SELECT x.f.value( '.', 'VARCHAR(35)' ) AS City FROM @Value.nodes( '//cities/city' ) x( f )

 );

使用“ ALL”标志将从@Value返回以下内容：

+-------------+
|    City     |
+-------------+
| Los Angeles |
| San Diego   |
| Fresno      |
+-------------+

在in子句sql server中连接字符串

2 个答案: