[jira] [Commented] (CONNECTORS-284) HSQLDB load test runs out of memory and has lots of very slow queries

["Karl Wright (Commented) (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CONNECTORS-284?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13142390#comment-13142390 ] 

Karl Wright commented on CONNECTORS-284:
----------------------------------------

Everything looks good for HSQLDB except for two things:

(1) The stuffer query does not read preferentially out of the order-by index, and there seems to be no good way to do that with HSQLDB.  Rule is that you must mention the order-by constraint in the WHERE clause for this to happen.  This means that you have to say something like "docpriority > 0".  The recommendation is thus to use a nested query (SELECT * from jobqueue where docpriority > 0 AND EXISTS(...) ORDER BY docpriority ASC) to force the read from the ordering index.  But since the state of document is not taken into account at this level it is possible that a lot of work would need to be done in pathological cases, unless I could guarantee that a doc priority only appeared at all if the document was in the right state.  I also don't want to break Postgresql, which I believe is capable of working with indexes of the form (ordering clauses, where clauses).

(2) The rules as far as the index matching are concerned in HSQLDB give precedence to non-parenthesized expressions over parenthesized ones, eg. (A or B or C) AND E will use an index on E preferentially.  I have to find a way to prevent this from messing up some of our queries.

                
> HSQLDB load test runs out of memory and has lots of very slow queries
> ---------------------------------------------------------------------
>
>                 Key: CONNECTORS-284
>                 URL: https://issues.apache.org/jira/browse/CONNECTORS-284
>             Project: ManifoldCF
>          Issue Type: Bug
>          Components: Framework core
>    Affects Versions: ManifoldCF 0.4
>            Reporter: Karl Wright
>            Assignee: Karl Wright
>             Fix For: ManifoldCF 0.4
>
>
> Some of the long-running queries are as follows:
> - document stuffer query
> - locating carrydown information

--
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