openjpa-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Pinaki Poddar (Created) (JIRA)" <j...@apache.org>
Subject [jira] [Created] (OPENJPA-2099) Reuse relationship selection
Date Fri, 23 Dec 2011 18:50:31 GMT
Reuse relationship selection 
-----------------------------

                 Key: OPENJPA-2099
                 URL: https://issues.apache.org/jira/browse/OPENJPA-2099
             Project: OpenJPA
          Issue Type: Improvement
            Reporter: Pinaki Poddar
            Assignee: Pinaki Poddar


Related entities are often loaded via a separate select operation when an unloaded field is
accessed. The select operation for a relationship field structurally (i.e. which tables it
joins to or what columns it selects) is invariant at instance level. Only thing that changes
across entity instances is the foreign/primary key identifier values used in joining. The
major computation cost is paid to analyze to build the select structure by analyzing the mapping
metadata of class/field involved. As noted, this computation is invariant for each instance
access except the primary/foreign key values involved. 
However, the core infrastructure for this frequent operation (because it is carried out whenever
a relationship field is loaded for every instance) is not designed for reuse. The select gets
constructed every time, the class/field mapping metadata gets analyzed every time, before
the select is executed on the database. 
What is required to avoid this repeated and unnecessary cost is to reuse a select instance
computed for every relationship field only once but binding different parameters on every
execution.      
The task is non-trivial because of the select abstraction (a highly complex and critical data
structure) is not designed with such parameter rebinding in mind. 
This issue attempts to remedy that limitation. 

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira

        

Mime
View raw message