如何创建 SQL 过程以从动态表中选择动态列

Question

I need to create procedure to select dynamic column from dynamic data where dynamic value

Craete procedure SelectColumn
@tableName NVARCHAR(MAX),
@id int,
@ColumnName NVARCHAR(MAX)

as
begin
DECLARE @SQLString1 NVARCHAR(MAX)
SET @SQLString1= 'Select '+ @ColumnName + ' From ' + @TableName +' where id= '+@id
    print @SQLString1
    EXEC (@SQLString1)
end

When execute show this error

Conversion failed when converting the nvarchar value 'Select Email From Member where id= ' to data type int.

when delete where id= '+@id and set 'where id=1' the procedure success, but I need use where id=@id .

Answer 1

试试这个CAST(@id AS VARCHAR)

SET @SQLString1= 'Select '+ @ColumnName + ' From ' + @TableName +' where id= '+CAST(@id AS VARCHAR)