在sql server中映射动态列名

DECLARE @step VARCHAR(25) = '15';
DECLARE @COL VARCHAR(50) = step_col_@step;
UPDATE table_tblName SET @COL=<some value> WHERE <condition>

I have the above query where @COL is supposed to be dynamic i.e. step_col_1,step_col_2,step_col_3......step_col_18. How can I achieve this without If-else condition in sql server?

我有上面的查询，其中@COL应该是动态的，即step_col_1，step_col_2，step_col_3 ...... step_col_18。如果没有SQL Server中的If-else条件，我该如何实现呢？

4 个解决方案

#1

Try the below query,

尝试以下查询，

DECLARE @COL VARCHAR(50) = 'step_col_'+@step

#2

Pass the variables like this to form a dynamic sql query

传递这样的变量以形成动态sql查询

DECLARE @step VARCHAR(25) = '15';
DECLARE @COL VARCHAR(50) = 'step_col_'+@step
exec ('UPDATE table_tblName SET '+@COL+'=<some value> WHERE <condition>')

#3

 DECLARE @step VARCHAR(25) = '15';
 DECLARE @COL VARCHAR(50) = 'step_col_'+@step;
 DECLARE @String VARCHAR(500) = ''
 SET @String = 'UPDATE table_tblName SET '''+@COL+''' = <some value> WHERE  
 <condition>' 
 EXEC (@String)

#4

DECLARE @step VARCHAR(25) = '15';
DECLARE @COL VARCHAR(50) 
SET @COL = 'step_col'+@step;

UPDATE table_tblName SET @COL=<some value> WHERE <condition>

#1