Hibernate 限制/标准初学者问题

发布于 2024-10-01 13:26:53 字数 1060 浏览 0 评论 0原文

嗨，我今天一直在尝试找出最好的方法，但没有成功。

理想情况下，我想做的是创建一个通过下面的 SQL 公式计算的别名距离（尽管我对计算距离的其他方法持开放态度，但这似乎是最简单的方法）

一旦我有了该别名，我希望能够以限制方式使用它来查找特定距离内的所有内容。

我还希望能够通过距离进行排序。

这是建立的更大搜索标准的一部分，因此我理想地希望继续使用 Criteria。（我已经限制了 Lat 和 Long 值的范围，以便在更少的字段上进行距离计算。

Criteria criteria = session.createCriteria(Activity.class)
       .createAlias("activityLocations", "actloc")
       .createAlias("actloc.location", "location")
       .createAlias("location.address", "addr");
       criteria.add((Restrictions.and(Restrictions.between("addr.latitude", latmin,     
       latmax),Restrictions.between("addr.longitude", truelongmin, truelongmax))));


       String sql =  "SQRT( POW( 69.1 * ( addr3_.latitude - " + point[1]     
       +" ) , 2 ) + POW( 69.1 * ( "+point[0] +" - addr3_.longitude ) * COS( addr3_.latitude /"
       +" 57.3 ) , 2 ) )  < "+distance;    
       criteria.add(Restrictions.sqlRestriction(sql));

目前我在 sql 查询中有 addr3_ ，因为我正在查看详细输出，这就是 Hibernate 生成查询的方式（这hack 在我正在查看的一个实例中起作用，但我害怕考虑长期影响，所以不希望它留在那里！！）

原文

Hi I have been trying to work out the best way to do this today to no avail.

What I would ideally like to do is to create an alias distance calculated by the SQL formula below (although I am open to other ways of calculating the distance, this was just the way that seemed it should be easiest)

Once I have that alias I want to be able to use it in a Restrictions fashion to find all that are within a certain distance.

I would also like to be able to sort via distance.

This is part of a bigger search criteria that is built up so I would ideally like to keep using Criteria. ( I already limit the range of Lat and Long values to make the distance calculation required on less fields.

Criteria criteria = session.createCriteria(Activity.class)
       .createAlias("activityLocations", "actloc")
       .createAlias("actloc.location", "location")
       .createAlias("location.address", "addr");
       criteria.add((Restrictions.and(Restrictions.between("addr.latitude", latmin,     
       latmax),Restrictions.between("addr.longitude", truelongmin, truelongmax))));


       String sql =  "SQRT( POW( 69.1 * ( addr3_.latitude - " + point[1]     
       +" ) , 2 ) + POW( 69.1 * ( "+point[0] +" - addr3_.longitude ) * COS( addr3_.latitude /"
       +" 57.3 ) , 2 ) )  < "+distance;    
       criteria.add(Restrictions.sqlRestriction(sql));

Currently I have addr3_ in the sql query because I was looking at the verbose output and that is the way that Hibernate has generated the query (this hack worked in the one instance i was looking at but I dread to think about the longer term implications so would not want it to stay there!!)

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风铃鹿 2024-10-08 13:26:54

在 SQL 限制中，您可以将条件根的别名引用为 {alias}。要在这种情况下使用它，您需要一个以 location.address 为根的“子条件”：

Criteria criteria = session.createCriteria(Activity.class) 
       .createAlias("activityLocations", "actloc") 
       .createAlias("actloc.location", "location");

Criteria addr = criteria.createCriteria("location.address"); 
addr.add((Restrictions.and(Restrictions.between("latitude", latmin,      
       latmax), Restrictions.between("longitude", truelongmin, truelongmax)))); 

String sql =  "SQRT( POW( 69.1 * ( {alias}.latitude - " + point[1]      
       +" ) , 2 ) + POW( 69.1 * ( "+point[0] +" - {alias}.longitude ) * COS( {alias}.latitude /" 
       +" 57.3 ) , 2 ) )  < "+distance;     
addr.add(Restrictions.sqlRestriction(sql));

In SQL restrictions you can refer to the alias of the criteria root as {alias}. To use it in this case, you need a "sub criteria" rooted at location.address:

Criteria criteria = session.createCriteria(Activity.class) 
       .createAlias("activityLocations", "actloc") 
       .createAlias("actloc.location", "location");

Criteria addr = criteria.createCriteria("location.address"); 
addr.add((Restrictions.and(Restrictions.between("latitude", latmin,      
       latmax), Restrictions.between("longitude", truelongmin, truelongmax)))); 

String sql =  "SQRT( POW( 69.1 * ( {alias}.latitude - " + point[1]      
       +" ) , 2 ) + POW( 69.1 * ( "+point[0] +" - {alias}.longitude ) * COS( {alias}.latitude /" 
       +" 57.3 ) , 2 ) )  < "+distance;     
addr.add(Restrictions.sqlRestriction(sql));

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