Hi,
Would it be possible to create an index as follows:
create index idx_TableA_k1_k2 on TableA(k1, k2)
and then delete 1000 rows at a time, until no more rows are found, using:
delete from TableA where K1='2012-01-01' and K2='ABC' limit 1000;
delete from TableA where K1='2012-01-01' and K2='ABC' limit 1000;
delete from TableA where K1='2012-01-01' and K2='ABC' limit 1000;
...
(until the updateCount is 0).
Regards,
Thomas
On Fri, Mar 30, 2012 at 5:25 PM, Hom L <[email protected]> wrote:
>
> The table created has two date fields , 11 varchar(255) and 9 double fields.
> The index contains the date field K1 and one varchar field K2.
>
> the index is like (K1,K2)
>
> the delete statement is like : delete from TableA where K1='2012-01-01' and
> K2='ABC'
>
> The only jdbc parameter used is LOCK_SCHEMA=0.
>
> now that I think about it. it might be that each line of table might contain
> too much space( those varchar(255) + doubles). I wonder if any other
> parameters that can help for such case.
>
>
>
> On Friday, March 30, 2012 10:33:55 PM UTC+8, Noel Grandin wrote:
>>
>> are you using an index?
>>
>> and what does the create table and delete statement look like?
>>
>> On 2012-03-30 15:12, Hom L wrote:
>> > Hi,
>> >
>> > I have created a H2 table with an index of several fields and loaded 2
>> > million records (the data file grows to 600 MB). When I tried to
>> > delete those data with the key, it takes about 5 minutes to do so.
>> >
>> > I have already set the LOCK MODE as 0. Is there any way to improve the
>> > performance.
>> >
>> > Regards,
>> > --
>
> --
> You received this message because you are subscribed to the Google Groups
> "H2 Database" group.
> To view this discussion on the web visit
> https://groups.google.com/d/msg/h2-database/-/e0ZR351D3_oJ.
>
> To post to this group, send email to [email protected].
> To unsubscribe from this group, send email to
> [email protected].
> For more options, visit this group at
> http://groups.google.com/group/h2-database?hl=en.
--
You received this message because you are subscribed to the Google Groups "H2
Database" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/h2-database?hl=en.
