使用交叉连接删除包含 null 的行

Question

我有我的代码：

SELECT Y.shipdate[Sent date], 
Rate_ = 'price' + Z.Which, 
Bill_ = 'bill' + Z.Which,
               Rate = CASE Z.Which
                    WHEN '1' THEN price1
                    WHEN '2' THEN price2 
                    WHEN '3' THEN price3
                    WHEN '4' THEN price4
                    WHEN '5' THEN price5
                    WHEN '6' THEN price6 END,
                Bill = CASE Z.Which 
                    WHEN '1' THEN bill1
                    WHEN '2' THEN bill2
                    WHEN '3' THEN bill3
                    WHEN '4' THEN bill4
                    WHEN '5' THEN bill5
                    WHEN '6' THEN billr6 END,        
   Y.duedate[Due Date], Y.recvdate[Received] 
   FROM tra Y
   CROSS JOIN (SELECT '1'  union ALL SELECT '2' UNION ALL  SELECT '3' UNION ALL  SELECT '4' UNION ALL  SELECT '5' UNION  ALL SELECT '6') Z (Which)  
   WHERE name = 'test'

输出：

Sent Date                   Rate_   Bill_   Rate    Bill    Due Date                  Received
2015-12-22 00:00:00.000     price1  bill1   0.55    300.00  2015-12-16 00:00:00.000   2015-12-01 00:00:00.000
2015-12-22 00:00:00.000     price2  bill2   0.04    2.00    2015-12-16 00:00:00.000   2015-12-01 00:00:00.000
2015-12-22 00:00:00.000     price3  bill3   0.07    43.00   2015-12-16 00:00:00.000   2015-12-01 00:00:00.000
2015-12-22 00:00:00.000     price4  bill4   0.00    0.00    2015-12-16 00:00:00.000   2015-12-01 00:00:00.000
2015-12-22 00:00:00.000     price5  bill5   0.00    0.00    2015-12-16 00:00:00.000   2015-12-01 00:00:00.000
2015-12-22 00:00:00.000     price6  bill6   0.00    0.00    2015-12-16 00:00:00.000   2015-12-01 00:00:00.000

我想要一个只显示价格和账单价值行的输出。根据我的示例，输出中应该只有 3 行。谢谢。

Answer 1

试试这个

where name = 'test'
and CASE Z.Which
         WHEN '1' THEN price1
         WHEN '2' THEN price2 
         WHEN '3' THEN price3
         WHEN '4' THEN price4
         WHEN '5' THEN price5
         WHEN '6' THEN price6 
    END <> 0.00

交叉连接产生两个表的笛卡尔积。与其他 JOIN 运算符不同，它不允许您指定连接子句。但在你的情况下，你正在使用过滤器来消除行。在这种情况下，最好使用 Natural Join

Answer 2

也可以通过其他方式实现，但这是最通用的方式，适用于大多数 RDBMS 系统。使用您的主查询作为子查询并给出 where 条件

SELECT * FROM (
SELECT Y.shipdate[Sent date], 
Rate_ = 'price' + Z.Which, 
Bill_ = 'bill' + Z.Which,
               Rate = CASE Z.Which
                    WHEN '1' THEN price1
                    WHEN '2' THEN price2 
                    WHEN '3' THEN price3
                    WHEN '4' THEN price4
                    WHEN '5' THEN price5
                    WHEN '6' THEN price6 END,
                Bill = CASE Z.Which 
                    WHEN '1' THEN bill1
                    WHEN '2' THEN bill2
                    WHEN '3' THEN bill3
                    WHEN '4' THEN bill4
                    WHEN '5' THEN bill5
                    WHEN '6' THEN bill6 END,        
   Y.duedate[Due Date], Y.recvdate[Received] 
   FROM tra Y
   CROSS JOIN (SELECT '1'  union ALL SELECT '2' UNION ALL  SELECT '3' UNION ALL  SELECT '4' UNION ALL  SELECT '5' UNION  ALL SELECT '6') Z (Which)  
   WHERE name = 'test' ) TMP_TAB
WHERE RATE <> 0 AND BILL <> 0

使用交叉连接删除包含 null 的行

remove rows that contains null using cross join

sql

cross-join