将行值显示为要在网格视图中显示的列[重复]

Question

我有一个 Mysql 数据库，其中一个表有两列 Department 和交易：

Department | deals 
HR         | A1  
Sales      | A2 
Revenue    | A1 
HR         | A3  

我想将asp.net gridview中的数据显示为：

         A1| A2 | A3 
HR       1    0    1
Sales    0    1    0
Revenue  1    0    0

如果交易下的值未知或不固定，我该如何做同样的事情。 我在下面使用，但它没有显示所需的输出

SELECT GROUP_CONCAT(CONVERT(deals,char(10)))
FROM Table1
group by Department

Answer 1

试试这个：

SELECT Department, 
       SUM(deals='A1') AS A1, 
       SUM(deals='A2') AS A2, 
       SUM(deals='A3') AS A3
FROM Table1
GROUP BY Department

对于Dynamic Deals：

SELECT GROUP_CONCAT(DISTINCT CONCAT("SUM(deals='", deals, "') AS '", deals, "'")) INTO @temp
FROM Table1;

SET @sql = CONCAT('SELECT Department, ', @temp, 'FROM Table1 GROUP BY Department');
PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

或

SELECT Department, 
       SUM(IF(deals='A1', 1, 0)) AS A1, 
       SUM(IF(deals='A2', 1, 0)) AS A2, 
       SUM(IF(deals='A3', 1, 0)) AS A3
FROM Table1
GROUP BY Department;

对于Dynamic Deals：

SELECT GROUP_CONCAT(DISTINCT CONCAT("SUM(IF(deals='", deals, "', 1, 0)) AS '", deals, "'")) INTO @temp
FROM Table1;

SET @sql = CONCAT('SELECT Department, ', @temp, 'FROM Table1 GROUP BY Department');
PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;