Question

我想知道如何从sql查询的输出中删除重复值。

这是sql查询：

$query = "SELECT useraccount.Username, tariff.Name as tariffs, 
energyconsumption.ElecEnergy, useraccount.Username as User
    FROM useraccount
    INNER JOIN tariff 
ON useraccount.tariffs = tariff.id
INNER JOIN energyconsumption
ON energyconsumption.User = useraccount.id
WHERE Date = CURRENT_DATE";

这是该查询的输出：

{"results":[{"Username":"absc868","TariffName":"s1","ElecConsump":"2000"},  
{"Username":"absc868","TariffName":"s1","ElecConsump":"1900"}]}

如您所见，查询过滤掉数据与当前日期匹配的数据。我们为同一个用户提供了2个输出。关税名称和用户名的价值是相同的，但能耗值是不同的，这很好。

我想实现以下输出：

= {"results":[{"Username":"absc868","TariffName":"s1","ElecConsump":"2000 +1900"}


= {"results":[{"Username":"absc868","TariffName":"s1","ElecConsump":"3900"}

有人能指出我如何实现这个目标吗？

提前感谢那些阅读帖子并做出贡献的人！

Answer 1

您可以使用group_concat功能：

$query = "SELECT useraccount.Username, tariff.Name as tariffs, 
GROUP_CONCAT(energyconsumption.ElecEnergy SEPARATOR ' +')
    FROM useraccount
    INNER JOIN tariff 
ON useraccount.tariffs = tariff.id
INNER JOIN energyconsumption
ON energyconsumption.User = useraccount.id
WHERE Date = CURRENT_DATE
GROUP BY useraccount.Username, tariff.Name";

Answer 2

你应该使用一个总和和一个小组

@EnableAutoConfiguration

（表列名别名和对象属性名称之间有一些区别）

如何从sql查询中删除重复值

2 个答案: