计算不同列中相同值的数量

如何解决计算不同列中相同值的数量

我有一个表，我想在其中计算不同列中相同值的数量。但是我还不知道如何实现它。请告诉我。

+---------+---------+---------+---------+---------+
| Field1  | Field_A | Field_B | Field_C | Field_D |
+---------+---------+---------+---------+---------+
| Value_A |    0    | 0       | 0       | 0       |
+---------+---------+---------+---------+---------+
| Value_A |    0    | 14      | 0       | 14      |
+---------+---------+---------+---------+---------+
| Value_A |    12   | 0       | 12      | 0       |
+---------+---------+---------+---------+---------+
| Value_A |    0    | 12      | 0       | 0       |
+---------+---------+---------+---------+---------+
| Value_A |    0    | 0       | 0       | 0       |
+---------+---------+---------+---------+---------+
| Value_A |    1    | 12      | 0       | 1       |
+---------+---------+---------+---------+---------+
| Value_A |    0    | 0       | 14      | 0       |
+---------+---------+---------+---------+---------+

最后我想得到以下结果

+---------+-------+-------+
| Field_A | Value | Count |
+---------+-------+-------+
| Value_A | 12    | 4     |
+---------+-------+-------+
| Value_A | 14    | 3     |
+---------+-------+-------+
| Value_A | 1     | 2     |
+---------+-------+-------+

解决方法

您可以在此处使用联合方法：

SELECT Field1,Field AS Value,COUNT(*) AS Count
FROM
(
    SELECT Field1,Field_A AS Field WHERE Field_A <> 0 FROM yourTable UNION ALL
    SELECT Field1,Field_B FROM yourTable WHERE Field_B <> 0 UNION ALL
    SELECT Field1,Field_C FROM yourTable WHERE Field_C <> 0 UNION ALL
    SELECT Field1,Field_D FROM yourTable WHERE Field_D <> 0
) t
GROUP BY Field1,Field;

请注意，由于您有此要求，这可能意味着原始表中的四个字段列实际上属于一个列，也许还有另一个新列可以说明该列数据的类型。

,

您可以使用CROSS APPLY来实现

@client.event
async def on_message(message):
    if message.content.startswith('!flip '):
        keyword = message.content.split('!flip ')[1]
        await start(keyword,message.channel)

使用UNPIVOT的另一种方法

DECLARE @table table (Field1 VARCHAR(10),Field_A int,Field_B int,Field_C int,Field_D int)

INSERT INTO @table 
values
('Value_A',0      ),('Value_A',14,14     ),12,1,1      ),0     );

SELECT Field1,t.Field,count(*) as countOfFields  FROM @table
cross apply
(
VALUES (Field_A),(Field_B),(Field_C),(Field_D)
) as t(Field)
GROUP BY Field1,t.Field

SELECT Field1,val,COUNT(*) FROM @table
unpivot (val for Field in ([Field_A],[Field_B],[Field_C],[Field_D])) AS U
GROUP BY Field1,VAL