You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@openjpa.apache.org by "Vermeulen (JIRA)" <ji...@apache.org> on 2012/11/21 14:03:58 UTC
[jira] [Updated] (OPENJPA-2299) N+1 select when eager fetching two
collection fields of the same entity type
[ https://issues.apache.org/jira/browse/OPENJPA-2299?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Vermeulen updated OPENJPA-2299:
-------------------------------
Attachment: OPENJPA-2299-tests.zip
Added an OpenJPA test case which shows the problem.
> N+1 select when eager fetching two collection fields of the same entity type
> ----------------------------------------------------------------------------
>
> Key: OPENJPA-2299
> URL: https://issues.apache.org/jira/browse/OPENJPA-2299
> Project: OpenJPA
> Issue Type: Bug
> Components: jdbc, jpa, performance
> Affects Versions: 2.3.0, 2.2.1
> Reporter: Vermeulen
> Attachments: OPENJPA-2299-tests.zip
>
>
> I have a ProductOrder entity that has two @OneToMany lists of ProductOrderLines. When selecting from ProductOrder, eager fetching does not seem to recurse into the second list so that each field of each ProductOrderLine in the second list is fetched using a separate "load field" operation.
> The problem does not occur when there is only one List.
> @Entity
> public class ProductOrder {
> @JoinColumn(name = "PLANNED_ORDER_ID")
> @OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
> private List<ProductOrderLine> plannedOrderLines = new ArrayList<ProductOrderLine>();
> @JoinColumn(name = "ACTUAL_ORDER_ID")
> @OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
> private List<ProductOrderLine> actualOrderLines = new ArrayList<ProductOrderLine>();
> Expected nr of queries: 1 (for Order) + 1 (for Order.plannedOrderLines) + 1 (for Order.actualOrderLines).
> Actual nr of queries: same as expected + 1 query for each field of each ProductOrderLine in Order.actualOrderLines.
> Same problem exists when using @JoinTable instead of @JoinColumn (JPA 2.0 only).
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira