选择mysql上的查询，根据条件从单个表中选择值

我有一个结构化的sql表

CREATE TABLE IF NOT EXISTS `engine4_user_fields_values` (
  `item_id` int(11) unsigned NOT NULL,
  `field_id` int(11) unsigned NOT NULL,
  `value` text COLLATE utf8_unicode_ci NOT NULL,
  PRIMARY KEY (`item_id`,`field_id`,`index`)
)

我想选择（5,8,7）中带有字段\u id='17'和值的行+字段\u id='20'和（73,76）中的值的行

我不能像下面给出的那样选择它，因为如果field_id是17，它就不会是20

SELECT * FROM `engine4_user_fields_values` WHERE (field_id ='17' AND value IN(5,8,7)) AND (field_id ='20' AND value IN(73,76))

如果我们使用OR，那么它将选择满足任何条件的值

我们可以用join吗？我不确定代码！

---

任何人请帮助我从您的描述中获取此

的select查询，听起来您应该更改中间和to或。您希望返回与第一个条件或第二个条件匹配的所有行。字段ID不能为17和20

SELECT * FROM `engine4_user_fields_values` WHERE (field_id ='17' AND value IN(5,8,7)) OR (field_id ='20' AND value IN(73,76))

SELECT * FROM `engine4_user_fields_values` WHERE (field_id ='17' AND value IN(5,8,7)) OR (field_id ='20' AND value IN(73,76))

---

您应该使用OR，但在两个子条件之间：

SELECT * 
FROM `engine4_user_fields_values` 
WHERE (field_id ='17' AND value IN(5,8,7))
OR (field_id ='20' AND value IN(73,76))

select  item_id
from    engine4_user_fields_values
group by
        item_id
having  max(case when field_id ='17' and value in (5,8,7) then 1 end) = 1
        and max(case when field_id ='20' and value in (73,76) then 1 end) = 1

---

您可以

按

项分组，并使用

having

子句要求该项具有与两个条件匹配的行：

SELECT * 
FROM `engine4_user_fields_values` 
WHERE (field_id ='17' AND value IN(5,8,7))
OR (field_id ='20' AND value IN(73,76))

select  item_id
from    engine4_user_fields_values
group by
        item_id
having  max(case when field_id ='17' and value in (5,8,7) then 1 end) = 1
        and max(case when field_id ='20' and value in (73,76) then 1 end) = 1

---

您正在使用+表示（5,8,7）中的字段\u id='17'和值）+字段\u id='20'和（73,76）中的值
因此，从技术上讲，不可能同时具有字段“id='17'和字段“id='20'”
您需要使用或代替和，如下所示