Re: bzr commit into mysql-5.1-bugteam branch (davi:2741) Bug#37016

[Davi Arnaut]

On 1/8/09 7:20 PM, Guilhem Bichot wrote:
> Hello,
>
> Davi Arnaut a écrit, Le 12/13/2008 11:58 AM:
>> # At a local mysql-5.1-bugteam repository of davi
>>
>> 2741 Davi Arnaut 2008-12-13
>> Bug#37016: TRUNCATE TABLE removes some rows but not all

[..]

>> + ha_autocommit_or_rollback(thd, 0);
>> + end_active_trans(thd);
>> +
>> DBUG_RETURN(error);
>> }
>
> The last 3 added lines above, are for a situation which is not
> row-by-row deletion, so what is the reason they are added (how do they
> relate to the bug report)?
> I believe you describe this change with "If the truncation is emulated
> by a table recreation, always issue a implicit commit", but, was there a
> problem at all when using table recreation? Why was the addition needed?
>

Table recreation can't be rolled back as some others DDL, so it's usual 
to issue a implicit commit before and after the statement is executed so 
that the TRUNCATE TABLE transaction is properly finished even in the 
recreation case.

This hasn't much impact on 5.1, but its important for the future as this 
will guarantee that metadata locks are released. On 6.0, almost all 
DDL's are automtically committed at the end. So, this is more of a 
cleanup for now. Any objections?

Regards,

-- Davi Arnaut