Обсуждение: Online DW
Hi
Is there any feature in PostgreSQL where online DW (Dataware housing) is possible ?
am looking for scenario like
1. Production DB will have CURRENT + LAST 7 DAYS data only
2. Archive/DW DB will have CURRENT + COMPLETE HISTORY
expecting something like streaming, but not ETL
Thanks
Sridhar
On 10 June 2016 at 16:11, Sridhar N Bamandlapally <sridhar.bn1@gmail.com> wrote:
HiIs there any feature in PostgreSQL where online DW (Dataware housing) is possible ?am looking for scenario like1. Production DB will have CURRENT + LAST 7 DAYS data only2. Archive/DW DB will have CURRENT + COMPLETE HISTORYexpecting something like streaming, but not ETL
There's nothing built-in, but that's exactly the sort of thing pglogical is intended for. You can also build something along those lines with Londiste fairly easily.
Hopefully this is the sort of thing we can move toward with built-in logical replication in coming releases.
One thing looks possible ( feature not available), just an idea
example/syntax:
BEGIN NOARCHIVE;
--- transaction-1
--- transaction-2
.
.
--- transaction-N
END;
This/These will be performed in Production to clean-up archive which will not be sync with Archive/DW DB only
one heads-up is Archive/DW DB may need to build WITHOUT CONSTRAINTS
May need to introduce ARCHIVE system/tag in pg_hba.conf
Thanks
Sridhar
OpenText
On Fri, Jun 10, 2016 at 2:22 PM, Craig Ringer <craig@2ndquadrant.com> wrote:
On 10 June 2016 at 16:11, Sridhar N Bamandlapally <sridhar.bn1@gmail.com> wrote:HiIs there any feature in PostgreSQL where online DW (Dataware housing) is possible ?am looking for scenario like1. Production DB will have CURRENT + LAST 7 DAYS data only2. Archive/DW DB will have CURRENT + COMPLETE HISTORYexpecting something like streaming, but not ETLThere's nothing built-in, but that's exactly the sort of thing pglogical is intended for. You can also build something along those lines with Londiste fairly easily.Hopefully this is the sort of thing we can move toward with built-in logical replication in coming releases.--
HiIs there any feature in PostgreSQL where online DW (Dataware housing) is possible ?am looking for scenario like1. Production DB will have CURRENT + LAST 7 DAYS data only2. Archive/DW DB will have CURRENT + COMPLETE HISTORYexpecting something like streaming, but not ETL
The entire DB couldn't operate this way since not every record has a concept of time and if you use any kind of physical time you are going to have issues as well.
First impression is you want to horizontally partition your "time-impacted" tables so that each partition contains only data having the same ISO Week number in the same ISO Year.
Remove older tables from the inheritance and stick them on a separate tablespace and/or stream them to another database.
As has been mentioned there are various tools out there today that can likely be used to fulfill whatever fundamental need you have. "Not ETL" is not a need though, its at best a "nice-to-have" unless you are willing to forgo any solution to your larger problem just because the implementation is not optimal.
Unless you define your true goals and constraints its going to be hard to make recommendations.
David J.
Ok, let me put this way,
I need every transaction coming from application sync with both production and archive db,
but the transactions I do to clean old data(before 7 days) on production db in daily maintenance window should not sync with archive db,
Archive db need read-only, used for maintaining integrity with other business applications
Issue here is,
1. etl is scheduler, cannot run on every transaction, even if it does, its expensive
2. Materialize view(refresh on commit) or slony, will also sync clean-up transactions
3. Replication is not archive, definitely not option
I say, every online archive db is use case for this.
Thanks
Sridhar
Opentext
On 10 Jun 2016 22:36, "David G. Johnston" <david.g.johnston@gmail.com> wrote:
HiIs there any feature in PostgreSQL where online DW (Dataware housing) is possible ?am looking for scenario like1. Production DB will have CURRENT + LAST 7 DAYS data only2. Archive/DW DB will have CURRENT + COMPLETE HISTORYexpecting something like streaming, but not ETLThe entire DB couldn't operate this way since not every record has a concept of time and if you use any kind of physical time you are going to have issues as well.First impression is you want to horizontally partition your "time-impacted" tables so that each partition contains only data having the same ISO Week number in the same ISO Year.Remove older tables from the inheritance and stick them on a separate tablespace and/or stream them to another database.As has been mentioned there are various tools out there today that can likely be used to fulfill whatever fundamental need you have. "Not ETL" is not a need though, its at best a "nice-to-have" unless you are willing to forgo any solution to your larger problem just because the implementation is not optimal.Unless you define your true goals and constraints its going to be hard to make recommendations.David J.
On 11 June 2016 at 12:29, Sridhar N Bamandlapally <sridhar.bn1@gmail.com> wrote:
I need every transaction coming from application sync with both production and archive db,
but the transactions I do to clean old data(before 7 days) on production db in daily maintenance window should not sync with archive db,
Archive db need read-only, used for maintaining integrity with other business applications
In a separate mail to -general I've asked Sridhar to keep this discussion to -general, not -hackers, from now on.