On 29/11/2010 16:56, Zhipan Wang wrote:
Since in-place seems not possible, I am trying to use arrays to store
different ranges of that column, and it's fast to fetch a big array,
so I believe an array is stored continuously on disk.
I can convert an array to a column easily by unnest() function,
ction that converts a column to an array. Is there a efficient
method to do that?
Thanks
- Original Message -
From: "Guillaume Lelarge"
To: "Zhipan Wang"
Cc: pgsql-general@postgresql.org
Sent: Sunday, November 28, 2010 12:59:46 AM GMT -08:00 US/Canada Pacific
Subject
> So the in-place update is a vital part of the program, because a range of
values
> of column col should be stored together on the disk. Is there any way to
do such
> a in-place update without generating much extra overhead?
>
Although in-place update is not possible, can he not use partitioning
Please send your answer (also) to the list.
Le 28/11/2010 10:23, zhipan Wang a écrit :
> [...]
> Thanks a lot for your detailed reply. I am trying to implement the idea
> proposed
> in the paper Database Cracking. The basic idea is like this:
>
> When a query with a range predicate like "a col
Le 27/11/2010 09:52, Zhipan Wang a écrit :
> Hi,
>
> I want to access part of a table on the disk sequentially, i,e., when I get
> to a tuple in the table, I need to read several pages of data in the table
> starting from this tuple.
You shouldn't rely on the order on disk. It will change as so
Hey Zhipan,
2010/11/27 Zhipan Wang
> Hi,
>
> I want to access part of a table on the disk sequentially, i,e., when I get
> to a tuple in the table, I need to read several pages of data in the table
> starting from this tuple. I guess CTID could be translated to physical
> address on the disk to
Hi,
I want to access part of a table on the disk sequentially, i,e., when I get to
a tuple in the table, I need to read several pages of data in the table
starting from this tuple. I guess CTID could be translated to physical address
on the disk to retrieve this tuple, right? If so, how do I us
