Thread: This whole MySQL versus PGSQL thing
OK, so I thought I'd do some more checking. MySQL is known for just swallowing what you give it and going on without raising an exception. numeric is also one of them SQL script in postgresql: create table testa (i1 numeric (4,2), i2 numeric(4,2)); insert into testa values (100.23,99.34); ERROR: overflow on numeric ABS(value) >= 10^2 for field with precision 4 scale 2 in mysql: create table testa (i1 numeric (4,2), i2 numeric(4,2)); insert into testa values (100.23,99.34); Query OK, 1 row affected (0.00 sec) insert into testa values (10000.23,99.34); Query OK, 1 row affected (0.00 sec) insert into testa values (100000.23,99.34); Query OK, 1 row affected (0.00 sec) select * from testa; +--------+-------+ | i1 | i2 | +--------+-------+ | 100.23 | 99.34 | | 999.99 | 99.34 | | 999.99 | 99.34 | | 999.99 | 99.34 | +--------+-------+ 4 rows in set (0.00 sec) Hope you weren't basing any accounting systems on this database. :-)
Hi there: I am just wondering how to remove the files of the database I just drop. I found there are whole bunch folders and files with number as the name. Once I drop the database, how do I know which files I should delete manually? Will the database engine delete that for me? Thanks!
"Terence Chang" <TChang@nqueue.com> writes:
> I am just wondering how to remove the files of the database I just drop. I
> found there are whole bunch folders and files with number as the name. Once
> I drop the database, how do I know which files I should delete manually?
Simple: none.
regards, tom lane
Great! That is easier than Oracle! Now! I have no excuse not to use PostgreSQL. :-) I got one more question! Is there a way that I can shut down only one database for "Cold Backup" while other database are running like Oracle does? Thanks!
Terence Chang wrote: > I got one more question! Is there a way that I can shut down only one > database for "Cold Backup" while other database are running like Oracle > does? No, but then again, there is no need. pg_dump will give you a consistent snapshot of the database as it was when you started the command. It is essentially a "cold" backup that is taken while hot! Joe
On Wed, 16 Jul 2003, Terence Chang wrote: > Great! That is easier than Oracle! Now! I have no excuse not to use > PostgreSQL. :-) > > I got one more question! Is there a way that I can shut down only one > database for "Cold Backup" while other database are running like Oracle > does? There's really no need to shut down and do a cold backup. pg_backup backs up databases hot as if they were cold (i.e. it uses a snapshot system). So, if you connect and start pg_dump, and 20 users initiate transactions after that, you see none of those later transactions or any part of them in your backup.
IC.. However, my application is critical. So is it possible to backup those 20 user's transactions from log? Oracle and MS SQL can recover to the failure point. Does PostgreSQL support that also? I mean recover from a transaction log and where is the transaction log? Thanks! ----- Original Message ----- From: "scott.marlowe" <scott.marlowe@ihs.com> To: "Terence Chang" <TChang@nqueue.com> Cc: <pgsql-general@postgresql.org> Sent: Thursday, July 17, 2003 7:35 AM Subject: Re: [GENERAL] Where is the physical files of database that I just > On Wed, 16 Jul 2003, Terence Chang wrote: > > > Great! That is easier than Oracle! Now! I have no excuse not to use > > PostgreSQL. :-) > > > > I got one more question! Is there a way that I can shut down only one > > database for "Cold Backup" while other database are running like Oracle > > does? > > There's really no need to shut down and do a cold backup. pg_backup backs > up databases hot as if they were cold (i.e. it uses a snapshot system). > So, if you connect and start pg_dump, and 20 users initiate transactions > after that, you see none of those later transactions or any part of them > in your backup. > > > ---------------------------(end of broadcast)--------------------------- > TIP 7: don't forget to increase your free space map settings
"Terence Chang" <TChang@nqueue.com> writes: > IC.. However, my application is critical. So is it possible to backup those > 20 user's transactions from log? Oracle and MS SQL can recover to the > failure point. Does PostgreSQL support that also? I mean recover from a > transaction log and where is the transaction log? Not yet. A lot of people have asked for that. The feature is being actively worked on but will not be in the upcoming 7.4 release. There's a good chance it will be in 7.5 (or whatever the release after that is called). -Doug