Re: deleting large objects from jdbc

heatherm@famoice.com wrote:
> Shouldn't the JDBC driver fix up things like that though?

This is how LargeObjects are designed to work in PostgreSQL.  Many
people consider this a good feature and depend on this functionality.
Unfortunately it works in a way that is different from other RDBMS, and
therefore people often don't realize the differences.  The documentation
certainly needs to be improved in this area.

thanks,
--Barry


>
> I've just changed my delete code, which was quite straight forward. My
> update code was more interesting. If the blob was updated then the
> lob_oid in my_table was changed and the new data put in the
> pg_largeobject table, but the old blob data was left there, orphaned.
> It's lucky I found out about this now and the beginning of development.
>
> Thanks
> Heather.
>
> -----Original Message-----
> From: barry [mailto:barry@xythos.com]
> Sent: Thursday, 9 August 2001 13:10
> To: Heather Murray
> Cc: barry; pgsql-jdbc
> Subject: Re: deleting large objects from jdbc
>
>
> Heather,
>
> Your understanding is correct.  You need to delete the large object
> when
> you no longer reference it in any other rows.  The SQL statements below
> should work for that purpose.
>
> thanks,
> --Barry
>
> heatherm@famoice.com wrote:
>
>>Hi,
>>
>>I've been browsing the newsgroup archives and came across the
>>
> following:
>
>>
>>>>>>>Can you see a scenario where a programmer would forget to
>>>>>>>
>>>>>>>
>>delete the
>>
>>
>>>>>>>data from pg_largeobject and the database becoming very large
>>>>>>>
>>>>>>>
>>filled
>>
>>
>>>>>>>with orphaned large objects?
>>>>>>>
>>>>>>>
>>Does this mean that to delete my large object I need to delete the
>>
> row
>
>>in my table, and also the row or rows in pg_largeobject. Currently I
>>
> am
>
>>only deleting the row in my table. I have just been looking at the
>>pg_largeobject table, it seems to have more rows than I would expect
>>
> in
>
>>it. Is the solution to pass these two commands to jdbc?
>>delete from my_table where lob_oid = 1234
>>delete from pg_largeobject where loid = 1234
>>
>>Thanks in advance
>>Heather.
>>
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