Php 将多个mysql查询组合成一个结果

我正在使用php从mysql表中获取结果。我想运行多个条件语句以返回唯一结果的列表。假设我在街上有一张关于房子的桌子，我的桌子是这样的：

House Number | Attribute | Value
-------------------------------
23           | Colour    | White
23           | Stories   | 2
24           | Stories   | 1
25           | Colour    | Blue

SELECT DISTINCT (`House_Number`) AS  `House_Number` 
FROM  `table` 
WHERE  `House_Number` 
IN (
    SELECT DISTINCT (`House_Number`) AS  `House_Number` 
    FROM  `table` 
    WHERE  `Attribute` =  'Colour'
    AND  `Value` =  'White'
)
AND  `Attribute` =  'Stories'
AND  `Value` =  '2';

SELECT DISTINCT(A.`House_Number`) AS  `House_Number`
FROM `table` AS A
INNER JOIN `table` AS B ON A.`House_Number` = B.`House_Number` 
WHERE A.Attribute =  'Colour'
AND A.Value =  'White'
AND B.Attribute =  'Stories'
AND B.Value =  '2'

House Number | Attribute | Value
-------------------------------
23           | Colour    | White
23           | Colour    | White
23           | Stories   | 2
24           | Stories   | 1
25           | Colour    | Blue 

请注意，房屋编号23出现了两次，我如何使用mysql查询返回所有白色且有两层楼的房屋？在这种情况下，它将只返回一个结果-23

我听到你在说什么了——为什么我不把“颜色”和“故事”列为列名呢。原因是，在我的例子中，房子可以有两种不同的颜色：同一属性名有两个不同的值。房子可以有两排，一排属性是颜色，价值是白色，另一排属性也是颜色，价值是紫色。只要房子有一行颜色为白色，一行故事为2，它就会在查询中返回正数并包含在结果中

现在，一个解决方案是运行两个不同的查询：一个查询匹配white House并返回一个数组，另一个查询匹配House with two stories并返回一个数组，然后我可以使用php比较这两个数组，查看两个数组中出现的条目，将它们取出并放入最终的数组中。但这涉及调用两个mysql查询。有没有办法在mysql端组合查询？

您想要一个自连接：

SELECT
  A.`House Number` AS House
FROM
  Houses AS A
  INNER JOIN Houses AS B ON A.`House Number`=B.`House Number`
WHERE
  A.Attribute='Colour' AND A.Value='White'
  AND B.Attribute='Stories' AND B.Value='2'

试试这个

  select id from table 
    where Attribute='Colour' and Value='White' 
    and id in (select id from table where Attribute='Stories' and Value='2')

---

您可以嵌套

选择
语句，如下所示：

House Number | Attribute | Value
-------------------------------
23           | Colour    | White
23           | Stories   | 2
24           | Stories   | 1
25           | Colour    | Blue

SELECT DISTINCT (`House_Number`) AS  `House_Number` 
FROM  `table` 
WHERE  `House_Number` 
IN (
    SELECT DISTINCT (`House_Number`) AS  `House_Number` 
    FROM  `table` 
    WHERE  `Attribute` =  'Colour'
    AND  `Value` =  'White'
)
AND  `Attribute` =  'Stories'
AND  `Value` =  '2';

SELECT DISTINCT(A.`House_Number`) AS  `House_Number`
FROM `table` AS A
INNER JOIN `table` AS B ON A.`House_Number` = B.`House_Number` 
WHERE A.Attribute =  'Colour'
AND A.Value =  'White'
AND B.Attribute =  'Stories'
AND B.Value =  '2'

House Number | Attribute | Value
-------------------------------
23           | Colour    | White
23           | Colour    | White
23           | Stories   | 2
24           | Stories   | 1
25           | Colour    | Blue 

编辑：
不像使用
内部联接那样漂亮，但仍然有效

< >在我输入我的原始响应的时候，在<代码>内部连接< /代码>方法欧根发布时，您可以考虑包括<代码>不同的< /代码>，像这样：

House Number | Attribute | Value
-------------------------------
23           | Colour    | White
23           | Stories   | 2
24           | Stories   | 1
25           | Colour    | Blue

SELECT DISTINCT (`House_Number`) AS  `House_Number` 
FROM  `table` 
WHERE  `House_Number` 
IN (
    SELECT DISTINCT (`House_Number`) AS  `House_Number` 
    FROM  `table` 
    WHERE  `Attribute` =  'Colour'
    AND  `Value` =  'White'
)
AND  `Attribute` =  'Stories'
AND  `Value` =  '2';

SELECT DISTINCT(A.`House_Number`) AS  `House_Number`
FROM `table` AS A
INNER JOIN `table` AS B ON A.`House_Number` = B.`House_Number` 
WHERE A.Attribute =  'Colour'
AND A.Value =  'White'
AND B.Attribute =  'Stories'
AND B.Value =  '2'

House Number | Attribute | Value
-------------------------------
23           | Colour    | White
23           | Colour    | White
23           | Stories   | 2
24           | Stories   | 1
25           | Colour    | Blue 

原因是，如果同一属性要记录两次，可以这样说：

House Number | Attribute | Value
-------------------------------
23           | Colour    | White
23           | Stories   | 2
24           | Stories   | 1
25           | Colour    | Blue

SELECT DISTINCT (`House_Number`) AS  `House_Number` 
FROM  `table` 
WHERE  `House_Number` 
IN (
    SELECT DISTINCT (`House_Number`) AS  `House_Number` 
    FROM  `table` 
    WHERE  `Attribute` =  'Colour'
    AND  `Value` =  'White'
)
AND  `Attribute` =  'Stories'
AND  `Value` =  '2';

SELECT DISTINCT(A.`House_Number`) AS  `House_Number`
FROM `table` AS A
INNER JOIN `table` AS B ON A.`House_Number` = B.`House_Number` 
WHERE A.Attribute =  'Colour'
AND A.Value =  'White'
AND B.Attribute =  'Stories'
AND B.Value =  '2'

House Number | Attribute | Value
-------------------------------
23           | Colour    | White
23           | Colour    | White
23           | Stories   | 2
24           | Stories   | 1
25           | Colour    | Blue 

…然后您将返回两次“23”，除非您使用了
DISTINCT
。虽然此查询确实有效，但请理解，在MySQL中的大表上使用子查询仍然会导致巨大的性能损失。这不是用户的错，而是MySQL中当前子查询实现中的一个怪癖，这一点很好。虽然此查询确实有效，但请理解，在MySQL中的大表上使用子查询仍然会导致巨大的性能损失。这不是用户的错，而是MySQL中当前子查询实现中的一个怪癖，这一点很好，OQ中没有给出，但我假设有两个完全相同的行，例如（23，颜色，白色）不符合应用程序的最佳利益-应使用唯一密钥或至少由应用程序拒绝。双方同意。保留子查询版本，以防它帮助那些还不熟悉连接的人，他们也更可能使用较小的表。此外，虽然确保数据表中没有重复记录是非常理想的，但会发生编码错误，并且会导入坏数据，因此我相信可以添加一些类似的调整，以防止潜在的下游问题。您关于重复行的输入非常有用+1-我本以为这是不可能的，但事实肯定不是这样！