OrientDB 使用子查询的结果来搜索索引 [英] OrientDB use result of subquery to search index

问题描述

我使用 OrientDb 2.1-rc4 作为文档数据库.我有一个 MyClass 类，它经常被多线程应用程序更新.为了提高性能，我删除了从 State 类到 MyClass 的链接，并添加了从 MyClass 到 State 的链接和索引. 为了获得 MyClass 的所有实例，我需要获得一个 State 列表，然后查询索引.这个查询让我的州摆脱了.

I am using OrientDb 2.1-rc4 as a document database. I have a MyClass class that gets updated very frequently by a multithreded application. To improve performance I removed the link from the State class to MyClass, and added a link and index from MyClass to State. In order to get all instances of MyClass I need to get a list of State rids and then query the index. This query gets my State rids.

SELECT DISTINCT(roles.views.states.@rid) 
FROM #12:1

返回

[["#14:0","#14:1"]]

此查询在索引中找到正确的rids.

This query finds the correct rids in the index.

SELECT FROM index:MyClass.state 
where key in [#14:0,#14:1] 

当我将两个查询放在一起时.

When I put the two queries together.

SELECT FROM index:MWorkUnit.state 
where key in (SELECT DISTINCT(roles.views.states.@rid) FROM #12:1) 

我收到以下错误.

java.lang.ClassCastException: com.orientechnologies.orient.core.sql.query.OSQLSynchQuery 不能转换为 java.util.List

java.lang.ClassCastException: com.orientechnologies.orient.core.sql.query.OSQLSynchQuery cannot be cast to java.util.List

如何让 OrientDB 将我的子查询视为删除列表?

How do I get OrientDB to treat my subquery as an rid list?

此查询在不使用索引时有效.

This query works when not using the index.

SELECT FROM MWorkUnit 
where state IN (SELECT expand(roles.views.states).@rid FROM #12:1)

推荐答案

这似乎是针对索引的查询的错误:子查询未正确评估.请问你能开一个新问题吗?

This seems a bug on query against indexes: sub queries are not correctly evaluated. Please could you open a new issue or that?

此解决方法应该有效:

SELECT FROM index:MWorkUnit.state 
LET $list = (SELECT DISTINCT(roles.views.states.@rid) FROM #12:1) 
where key in $list

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