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From "Dag H. Wanvik" <dag.wan...@oracle.com>
Subject Re: Implicit commit and end of SYSCS_UTIL.SYSCS_IMPORT_TABLE?
Date Mon, 04 Nov 2013 21:19:09 GMT
Thanks, Mike. Answers inlined.

On 04. nov. 2013 19:54, mike matrigali wrote:
> I think you must be right, and likely we should document it.
>
> For performance during import with replace the system does not
> log each insert, instead it "knows" that it can abort by just
> putting an empty table.  If you don't commit after this then
> I think you start getting a mix of log records in the abort
> stream.

Yes, that makes sense.

> At least in 10.7 doc we note that derby does this commit, but the
> section seems to have disappeared in later releases:
> http://db.apache.org/derby/docs/10.7/tools/ctoolsimport27052.html

It has moved to the admin guide:

http://db.apache.org/derby/docs/10.10/adminguide/cadminimport27052.html

In addition this this material, the individual import/export procedures 
in the reference manual should carry this important information, I think.

Dag



>
> it says:
> Database transactions
>     You should issue either a COMMIT or ROLLBACK statement to complete 
> all transactions and release all table-level locks before you invoke 
> an import or export procedure. Derby issues a COMMIT or a ROLLBACK 
> statement after each import and export procedure is run.
>     Note: Imports are transactional. If an error occurs during bulk 
> import, all changes are rolled back.
>
> On 11/4/2013 8:37 AM, Dag H. Wanvik wrote:
>> Hi,
>>
>> I read our reference manual for import table, but it doesn't mention
>> this. Can anyone explain why we
>> do an implicit commit? I thought the import statement was transactional;
>> I can imagine
>> it's because with replace option we truncate the old table would roll
>> back not via the log but by undoing the creation of a replacement
>> conglomerate.
>>
>> In any case, the reference manual should mention this prominently, I 
>> think.
>>
>> Code reference: line 1580
>> http://svn.apache.org/viewvc/db/derby/code/branches/10.10/java/engine/org/apache/derby/catalog/SystemProcedures.java?view=markup

>>
>>
>>
>> I'll file a doc issue if this is as it should be.
>>
>> Thanks,
>> Dag
>>
>


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