SQL/HQL 查询：查找具有匹配某些参数的对象列表的对象

Question

我有这些实体：

假设我收到这个 map<String,String>:

"gender": "male"

"age": "30"

我需要从地图中找到具有包含所有这些key/values 的TargetGroup 的活动。示例：

Map<String,String> keyValueParameters = new HashMap<String,String>(); keyValueParameters.put("gender","male"); keyValueParameters.put("age","30"); List<Campaign> campaignsResult = getCampaigns(keyValueParameters); Campaign aCampaign = campaignsResult.get(someIndex); TargetGroup aTargetGroup = aCampaign.getTargetGroup(); List<TargetValue> targetValues = aTargetGroup.getTargetValues(); targetValues.get(x).getKey() //"gender" targetValues.get(x).getValue() //"male" targetValues.get(y).getKey() //"age" targetValues.get(y).getValue() //"30" targetValues.get(z).getKey() //some other key

Answer 1

查询 returns 目标组列表，同时具有 key/value 对。（条件 count

的 HAVING 部分中的 2

SELECT targetGroupID
FROM TargetGroup tg
     INNER JOIN TargetValue tv ON tg.targetGourpId=tv.targetGourpId
WHERE (tv.key='gender' and tv.value='male')
   OR (tv.key='age' and tv.value='30')
GROUP BY targetGroupID
HAVING COUNT(targetGroupID)>=2

然后我们可以使用上面的查询来获得合适的活动

SELECT * 
FROM Campaign c
     INNER JOIN (the select above) as sub ON c.targetGroupID=sub.targetGroupID

我几乎不可能使用纯休眠。 HAVING 可能是个问题。你可以尝试为此编写自己的hql。

SQL/HQL 查询：查找具有匹配某些参数的对象列表的对象

SQL/HQL Query: find object that has a list of objects that matchs some parameters

java

sql

postgresql

hibernate

hql