Nikita Timofeev created CAY-2468:
------------------------------------
Summary: Support subqueries in Expression API
Key: CAY-2468
URL: https://issues.apache.org/jira/browse/CAY-2468
Project: Cayenne
Issue Type: Task
Components: Core Library, Database integration
Reporter: Nikita Timofeev
Assignee: Nikita Timofeev
Fix For: 4.2.M1
Currently there is no way to use subqueries in {{SelectQuery}} or
{{ObjectSelect}}.
So we need a way to do so, natural way of doing so is to support it in
{{Expression}} API.
Simple version can be implemented like this: {code}
ObjectSelect<Painting> subquery = ObjectSelect.query(...);
long count = ObjectSelect.query(Artist.class)
.where(ExpressionFactory.exists(subquery))
.selectCount(context);
{code}
Also we need a way to use expressions from top level query in a subquery. Maybe
it can be new expression (like {{Artist.ARTIST_NAME.enclosing()}})
In a first iteration this should support {{EXISTS}} and {{IN}} subqueries.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
