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From John English ...@brighton.ac.uk>
Subject java.lang.OutOfMemoryError
Date Wed, 13 Feb 2008 22:48:13 GMT
I have a table containing about 22000 records defined as follows:

CREATE TABLE system_log (
   id          INTEGER       GENERATED ALWAYS AS IDENTITY,
   time        TIMESTAMP     DEFAULT NULL,
   username    VARCHAR(15),
   facility    VARCHAR(15)   NOT NULL,
   event       VARCHAR(31)   NOT NULL,
   module      VARCHAR(15),
   test        VARCHAR(255),
   details     VARCHAR(32000),
   CONSTRAINT systemlog_pk   PRIMARY KEY (id)
);

I format this for display using a view defined like this:

CREATE VIEW system_log_view AS
     SELECT  TimeFormat(time) AS x_time,
             facility,
             event,
             details,
             NameFormat(surname,initials) AS name,
             system_log.username AS username,
             module,
             test,
             time,
             id
     FROM    system_log LEFT JOIN users
     ON      system_log.username=users.username

I then display the log using "SELECT * FROM system_log_view", which takes
about a minute to execute. (Taking out the join on the users table and just
displaying usernames rather than surnames and initials takes a few seconds
off, but not much.)

When I try to display it sorted into descending order of time (SELECT * FROM
system_log_view ORDER BY time DESC) I often (but not always) get a 
java.lang.OutOfMemoryError. The "not always" is presumably down to overall
system loading, but it's running on a reasonably powerful machine (a 64 bit
Linux system with about 4G of memory and loads of disk space).

Can anyone suggest what I can do to prevent this, or at least to narrow down
the reasons for the error? My last-ditch "catch Throwable" handler doesn't
give me a stack frame dump so it's hard to tell what's really going on.

TIA,

----------------------------------------------------------------------
  John English              | mailto:je@brighton.ac.uk
  Senior Lecturer           | http://www.it.bton.ac.uk/staff/je
  School of Computing & MIS | "Those who don't know their history
  University of Brighton    |  are condemned to relive it" (Santayana)
----------------------------------------------------------------------

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