Many comments (related to "Are we losing momentum?")
Hello all
In earlier threads on the Hackers mailing list there were discussions of a few things that I would like to comment on. Sorry in advance for the length of this post.
First, PostgreSQL needs 2PC AND eager replication AND lazy replication all at the same time. Of those however, I think Postgres would get the most bang for the buck by supporting 2PC and eager (postgres-r) asap. Add lazy replication when you can later. (Besides 2PC, and postgres-r seem to be closer to completion and integration with the main postgres development tree)
Also, 2PC and eager replication should work together simultaneously. Why?....
I may want performance and reliability provided by eager replication, but I also need to update the database and perform some operations on a pair of queues as a single transaction. In order for this to be possible we need both replication and 2PC, and they have to work together! In this situation 2PC and replication have to be developed with knowledge of each other. Lazy replication could be added to this situation later without to much effect.
Another thing I noted is that people are asking for 2PC with the JDBC driver. Obviously that can only happen when the database supports the feature. However, from what I last saw on the JDBC list archives it doesn't appear as if the JDBC driver developers know you guys are changing the FE/BE protocol and may soon be adding 2PC. I think the JDBC developers should be made aware of this asap... If all of a sudden the JDBC driver doesn't work with the newest version of Postgres there is going to be some upset people! You should also ask the JDBC driver developers to take part in the discussions of the new FE/BE protocol (if they aren't already). 2PC / XA resources in the JDBC driver will provide a very large boon to Postgres in the Java / J2EE arena.
Second, PostgreSQL needs to run as a production grade system on Windows if you want to increase "mind share". Why?....
Postgres is great, and free ($) but if you can only run a "production" system on UN*X there is a cost as far as a windows developer is concerned. That cost is the time and effort required to learn some flavor of UN*X in order to deploy the database. That is a very significant investment in time ($) to learn and money ($) for books. (Yes you can learn everything you need online for free, but who is going to do that... People buy books.)
When you get a production quality Postgres on Windows you will be immediately increasing the potential user base for Postgres and that will have a very large effect on the "mind share" postgres has. I would bet one of the reasons MySQL is so popular is because a Windows developer can just install a binary and use it on their systems.
Also a very important point everyone seemed to miss in regards to MySQL is that you CAN use it in a "commercial" environment as long as you are not distributing your product. I.E. if you create an app only to be used by your company internally, then the company doesn't need to buy a MySQL license. Also, if the company downloads some open source software, and downloads MySQL, and deploys them both for internal use it is not required to purchase a license for MySQL.
Why do I KNOW all this? Because I am a Windows user / Java developer, who has been spending a lot of time ($) and money on books ($) to learn Linux (Because it is awesome!)... I also spent a lot of time going over MySQL, Postgres, Firebird, SAPDB and even the old Sybase version that was released for Linux. Ive also worked (at work) with Oracle, DB2, MS-SQL.
Postgres should not and is not competing with MySQL, and that should not be your focus. Postgres is competing with Oracle, MS-SQL, DB2, Sybase, Firebird, etc. Why?...
For a few reasons:
1) Some MySQL users have a near religious affiliation with MySQL. You will never convert these people. Don't even try.
2) Some MySQL users are Windows users who would use any open source database they can, as long as they can run it on Windows in a "production" setting. For these users Postgres is not an option for the moment. When Postgres Win32 is available (and production grade) I think many of these users will begin investigating it. Until recently the only option for an open source DB on Windows was MySQL. (Now you have Firebird, SAPDB, and probably others). So yes in some aspect you are competing with MySQL here... But why compete, just make the best product you can and let the user decide which one they want to use.
3) Some MySQL users only need what MySQL provides. There is no incentive for these users to switch; the system they know does what they need.
Don't try to compete with MySQL it's a waste of time.
DO compete with Oracle, etc..
1) Postgres is a contender in many significant areas to the commercial DB's. When postgres has replication and 2PC this will definitely increase the threat that Postgres is to the commercial DB market.
2) Users who need triggers, stored procedures, etc. cannot consider MySQL.. it doesn't support those features (at the moment). They can look at Postgres, SAPDB, Firebird, and the commercial DB's. To compete Postgres has to be better than these other options.
What makes Postgres the better solution in this arena?
a) price - although remember the related costs I mentioned above. Also firebird and SAPDB are free and run on Windows, so they may have a "lower price" for Windows developers for the moment. Postgres Win32 will help us in this area.
b) reliability - no, all the DB's are fairly reliable. (lets not waste time discussing this one ok folks)
c) XA resources in Java, 2PC.. No, we don't have it yet.. We need it. I think the firebird JDBC driver has this already. This sounds like its coming in 7.4.
d) Replication - no, we don't have it yet.. We need it. Sounds like master slave is coming in 7.4. We need to get multi-master soon. You can already do multi-master replication in MySQL. (Yes we all know that what they have for replication is not as robust, especially if you use it in multi-master (circular replication a->b->c->a) but at least they have something. Lets not waste our time discussing what they have.. Lets instead spend that time building an even better solution for Postgres.)
e) cross-db queries - no, we don't have it yet.. We need it. (extend postgres views capability, dblink and use 2pc? See earlier post).
f) stored procedures that return result sets (tuples). Postgres finally got that in 7.3.
g) insert your needed feature here
If Postgres had 2pc, and Replication that would definitely move it closer to killing the commercial db's. 2pc is a building block to getting cross-db queries (across servers).
So, from the above RIGHT NOW Postgres is NOT a better solution than the commercial DBs except in the area of price And that is true only for people already familiar with UN*X. Dont get me wrong here folks I love Postgres.. Its just time for us to take a step back and look at the facts, and the facts are Postgres needs even more to be truly competitive where it should be competing. (Not competing with MySQL.) I think many of the features Postgres needs to be a better competitor are coming in the 7.4 release.
Other things that can / need to be done to increase Postgres mind share.
a) Embrace the Java community. The Java community has very good and close ties to the open source community. This is obvious because of the numerous open source projects in and for java. Jakarta.apache.org and all the frameworks on it like log4j, Struts, etc. Free open source J2EE app servers like Jboss, Jonas, etc.. However, the JDBC driver for Postgres is HARD TO FIND! Its hard to find because someone new to postgres cant find anything about it on the Postgresql.org home page. There is no link to it, and no mention of it. Granted the JDBC driver can be found by searching google, and by looking in the interfaces folder of the download. But a new Java visitor may not search google, and probably wont bother to download Postgres if they dont think it supports JDBC. Also, Postgres supports many different languages for use in functions and stored procedures, but it doesnt support Java. Many commercial DBs do. Maybe Postgres should consider adding support for Java in this area? (I dont think this is overly important, its just something else that could be done.)
b) The Postgres group has done a lot to improve the homepage of Postgresql.org. But when you click on most links it takes you to another site with a completely different look and feel. The side effect of this is that the Postgres project looks as if it is un-organized. Even more needs to be done in this area. The postgres site should be more cohesive with a single look and feel for as much of the site and its links as possible. Look at apache.org. They have MANY projects going on, but have a singular (or at least very similar) look and feel across most of their projects. You want a real shocker Visit the gborg homepage (click the gborg link on the bottom left corner of the postgres site). Then read the news on the right side of the gborg homepage. See that url for http://www.greatbridge.org/ in the GreatBridge.Org Version 2.0.0 Release story from way back in 2001! Go ahead, visit that URL. Whats the first thing you see on that page? Purchase IBM DB2 At IBM.com. Come on! Not even a mention of Postgres, and this is right on the gborg homepage! The firebird, sapdb and mysql sites are killing postgres here. The postgres homepage and related links is the first thing someone new to postgres sees! There shouldnt be news on any of the main pages from back in 2001. It looks like nothing is going on with Postgres. There has got to be more recent news that can be put up. Also, going back to the Java thing, the link for PostgreSQL JDBC 2.0 API compliance on the JDBC homepage goes to a dead link and has been that way for weeks. What does this tell a new person looking to use Postgres from Java?
I could keep going here, but this message is long enough already
Basically my points are:
1) Postgres IS GREAT, but for the moment the real competition (Commercial DBs) are providing more features. We need to catch up in some areas, and provide things they cant in others (easy / free / safe / multi-master eager replication)
2) We shouldnt be competing with MySQL.
3) Postgres may be great, but the perception given by collection of sites for postgres is that the project is un-organized. All the other open source DBs have a better look / feel / organization in this area.
Later
Rob
-----Original Message-----
From: Rob Butler [mailto:robert.butler5@verizon.net]
Sent: 16 April 2003 16:33
To: pgsql-hackers@postgresql.org
Subject: [HACKERS] Many comments (related to "Are we losing
momentum?")You
want a real shocker... Visit the gborg homepage (click the
gborg link on the bottom left corner of the postgres site).
Then read the news on the right side of the gborg homepage.
See that url for http://www.greatbridge.org/ in the
GreatBridge.Org Version 2.0.0 Release story from way back in
2001! Go ahead, visit that URL. What's the first thing you
see on that page? "Purchase IBM DB2 At IBM.com". Come on!
Not even a mention of Postgres, and this is right on the
gborg homepage!
We don't own that site, and we never did. We did manage to inherit the
projects database through it's key programmer and his goodwill.
The firebird, sapdb and mysql sites are
killing postgres here. The postgres homepage and related
links is the first thing someone new to postgres sees! There
shouldn't be news on any of the main pages from back in 2001.
There isn't. The oldest news is from January 2003.
Wrt your comments on the style of some of the pages linked off the main
site (the archives spring to mind), if there are any volunteers to help
fix that, please raise your hands because my time is limited and I could
do with some committed help on that sort of thing.
Regards, Dave.
Import Notes
Resolved by subject fallback
On Wed, 2003-04-16 at 11:51, Dave Page wrote:
-----Original Message-----
From: Rob Butler [mailto:robert.butler5@verizon.net]
Sent: 16 April 2003 16:33
To: pgsql-hackers@postgresql.org
Subject: [HACKERS] Many comments (related to "Are we losing
momentum?")You
want a real shocker... Visit the gborg homepage (click the
gborg link on the bottom left corner of the postgres site).
Then read the news on the right side of the gborg homepage.
See that url for http://www.greatbridge.org/ in the
GreatBridge.Org Version 2.0.0 Release story from way back in
2001! Go ahead, visit that URL. What's the first thing you
see on that page? "Purchase IBM DB2 At IBM.com". Come on!
Not even a mention of Postgres, and this is right on the
gborg homepage!We don't own that site, and we never did. We did manage to inherit the
projects database through it's key programmer and his goodwill.
Oddly I don't see the link he's referring to, but I've always thought it
unfortunate that the postgresql community didn't hold onto those domain
names. I was just speaking with a tech writer last night who mentioned
how the company that was initially behind postgresql went kaput ("I
think it was called great river or something?") Took me a minute to set
him straight on that.
Anyways, I've offered to look into setting up gforge services in the
past as it's a mature project with a good development community and the
founder (Tim Perdue) has always been friendly with the PostgreSQL
community. Course I don't see this as an immediate need, but long term I
think it would be a good idea.
The firebird, sapdb and mysql sites are
killing postgres here. The postgres homepage and related
links is the first thing someone new to postgres sees! There
shouldn't be news on any of the main pages from back in 2001.There isn't. The oldest news is from January 2003.
Wrt your comments on the style of some of the pages linked off the main
site (the archives spring to mind), if there are any volunteers to help
fix that, please raise your hands because my time is limited and I could
do with some committed help on that sort of thing.
I'm in the process of adding the newsletters to the main page (expect
questions your way later today ;-) but once I am done with that
"cohesiveness" will definitely be on my radar screen.
Robert Treat
Oddly I don't see the link he's referring to, but I've always thought it
unfortunate that the postgresql community didn't hold onto those domain
names.
Hmm, very odd. I just went out to: http://gborg.postgresql.org/project/gborg/projdisplay.php today by following the link from the postgres homepage. On the right side the oldest news story is all the way back to 2000.
Copied the last news stories on the page to show it's really there. Perhaps it
could be the proxy server I'm behind? The newest story is "Additional Project
Configuration Options Available".
ryan : 03/22/2001
GreatBridge.Org Version 2.0.0 Release
The latest version of GreatBridge.Org's GBSite, version 2.0.0, has been released and http://www.greatbridge.org/ is now running the new version. Version 2.0.0 is just the latest enhancements for GreatBridge.org and includes many changes based on user feedback, as well as extra functionality we know everyone will like.
Current users of our site will notice the enhanced bug and task tools,
including advanced searches, search memory for last search and default search.
Tools for admins and users of the site to receive bug/task change notifications
have also been added. In addition, we have also added the ability for admins to
have news and bugs sent to their mailing lists when items are added or
modified. New functional areas include project-specific FAQ pages and Feature
Request tools.
We encourage and hope our users and fellow developers will take advantage of
all of these new features. We encourage your feedback and suggestions to help
GreatBridge.Org to be the best open source development tool on the internet.
(full story...)
ryan : 02/23/2001
GBorg GBSite version 1.1.1 (Happy New Year)
Just in time for the New Year Great Bridge has released the latest version of
our GBorg GBSite application. We added several small additions including, but
not limited to:
Additional Bug/Task selection "Not Closed"
Errata page and manager
Show Bug counts on Project Home page
Show Bug Comment counts on Bug List page
Show counts of projects in Project Categories
fixed several minor bugs
(full story...)
ryan : 12/28/2000
GBorg GBSite Version 1.1.0 Released
The new version of the site is now up and running and available for download.
One of the best new features is the ability to add comments to bugs. Check it
out as I will be filling comments in on some of the more recent bugs so you can
see what we are doing with the problems you have found!
(full story...)
ryan : 12/11/2000
GreatBridge.org Preps For Ver 1.1
The GBORG project team is currently working on delivering version 1.1 by
December 8. This version will feature a few new areas. These include:
Errata Manager
FTP Upload Access
Bug Enhancements
Online Mailing List Response
Code Snippets
To learn more about these features, visit the GBORG project and check the task
list.
Thanks to everyone for their support. If you have any ideas or suggestions for
further improvement, drop us a line.
(full story...)
Import Notes
Resolved by subject fallback
Robert Treat <xzilla@users.sourceforge.net> writes:
Oddly I don't see the link he's referring to, but I've always thought it
unfortunate that the postgresql community didn't hold onto those domain
names.
We were not offered the chance; Landmark wanted to hold onto the Great
Bridge trademark, apparently. We did come away with the postgres.com,
postgres.org, and postgresql.com domains, which GB had managed to wrestle
away from some korean domain squatter.
The fact that some of those aren't currently resolving nicely (eg,
www.postgres.org gets you a Horde login page) is our own darn fault.
As Dave Page was mentioning, some additional hands in the webpage
maintenance effort would be great.
regards, tom lane
Rob Butler <robert.butler5@verizon.net> writes:
Hmm, very odd. I just went out to: http://gborg.postgresql.org/project/gborg/projdisplay.php today by following the link from the postgres homepage. On the right side the oldest news story is all the way back to 2000.
It looks like the links embedded in those news stories still point at
www.greatbridge.org, which domain apparently has lapsed and been
snatched up by a Hong Kong domain squatter :-(.
I dunno whether it's still appropriate to keep three-year-old news on
the project page, but if it is, updating the links to point at
gborg.postgresql.org would be good ...
regards, tom lane
On Wed, 2003-04-16 at 13:29, Tom Lane wrote:
Robert Treat <xzilla@users.sourceforge.net> writes:
Oddly I don't see the link he's referring to, but I've always thought it
unfortunate that the postgresql community didn't hold onto those domain
names.We were not offered the chance; Landmark wanted to hold onto the Great
Bridge trademark, apparently. We did come away with the postgres.com,
postgres.org, and postgresql.com domains, which GB had managed to wrestle
away from some korean domain squatter.
Sorry. I knew that but I guess my statement implied different.
The fact that some of those aren't currently resolving nicely (eg,
www.postgres.org gets you a Horde login page) is our own darn fault.
As Dave Page was mentioning, some additional hands in the webpage
maintenance effort would be great.
Well, that's more of a DNS issue than a webpage, and afaik Marc is the
only one who can make that change. If he's willing to change it now by
all means let's do so. If he's too busy but willing to give someone else
access to do it I'm sure we can dig someone up (like me)
Robert Treat
Glad to see all the comments about the web page stuff, and see that people
recognize the need for a cohesive look and feel for Postgres.org. Do people
have any comments about the rest of the stuff in my post?
Like, are the JDBC developers aware that you will be changing the FE/BE
protocol? Do they know you will (possibly) be adding 2PC?
Any communication going on between core and postgres-r developers to make
sure that replication and 2PC will work together simultaneously as I
described in my earlier e-mail?
Any comments about the section on competition? Do people agree / disagree
that postgres should not be competing with MySQL (because it's no real
competition) or does everyone think MySQL is a real threat? Do people agree
/ disagree that the real competition is commercial DB's and Firebird / SAP
db?
Later
Rob
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Any comments about the section on competition? Do people agree / disagree
that postgres should not be competing with MySQL (because it's no real
competition) or does everyone think MySQL is a real threat? Do people
agree / disagree that the real competition is commercial DB's and Firebird
/ SAP db?
There has been plenty of discussion on the advocacy list about this: it is
a much better place for this sort of talk than hackers anyway.
- --
Greg Sabino Mullane greg@turnstep.com
PGP Key: 0x14964AC8 200304161743
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"Rob Butler" <robert.butler5@verizon.net> writes:
Like, are the JDBC developers aware that you will be changing the FE/BE
protocol?
The ones who have been participating in the discussion are ;-)
Do they know you will (possibly) be adding 2PC?
The odds of that appearing in 7.4 are nil, IMHO.
regards, tom lane
-----Original Message-----
From: Rob Butler [mailto:robert.butler5@verizon.net]
Sent: 16 April 2003 17:48
To: pgsql-hackers@postgresql.org
Subject: Re: [HACKERS] Many comments (related to "Are we
losing momentum?")Oddly I don't see the link he's referring to, but I've
always thought
it unfortunate that the postgresql community didn't hold onto those
domain names.Hmm, very odd. I just went out to:
http://gborg.postgresql.org/project/gborg/projdisplay.php
today by following the link from the postgres homepage. On
the right side the oldest news story is all the way back to 2000.
That news is relevant to the Gborg project itself - i.e. the codebase
that drives gborg.postgresql.org. Each project on Gborg can maintain
it's own news, and it's down to the project members to do so, not us.
Regards, Dave.
Import Notes
Resolved by subject fallback
I am not a hacker of PgSQL, and new to Databases. I was using MySQL
under .NET, but was annoyed by their agressive licence agreements and
immaturity. (Their sales personel are also very rude. One girl once
told me that if I didn't like their licence terms I should just use
flat-files instead.) One of the .NET developers for MySQL advised me to
look at PostgreSQL, and I have never looked back.
This was not the fist time I looked at PostgreSQL, I initially looked at
30+ Databases, but rejected PostgreSQL off hand. There was no Windows
version.
Speaking stricktly as an ameture, I would like to make a few comments I
could not see mensioned in this thread. This is not a dig, more a wish
list!
Because: With the expanding industry and popularity of IT as part of
unrelated collage courses (Engineering, Accountancy etc), there are lots
of ametures and newbe's. We will never be first class hackers, we will
probably never get to the end of the manuals or understand what P2C /
FE/BE is or where it's used. But we are the silent magority. (I am
personally extreamly dyslexic. I learn from example, talking and brief
painful trips into the documentation archives.)
Therefore we learn as much as we need to know. In time I am sure we all
want to be guru's in everything. I have lots of ameture friends at this
level, running ISP's, producing commercial applications, in unrelated
research, needing office systems... All needing a DB. Most using
MS-SQL or MySQL.
To draw on a popular examples, MySQL helps the ameture: (I'm putting my
foot in it that some of this probably exists. I just haven't found it yet.)
- A true Windows version which people can learn their craft on.
- Tools which look like Access, to do row level data editing with no SQL.
- Easy to use and remember command extensions, like 'CREATE IF NOT
EXISTS', 'DROP IF EXISTS' which are universal.
- Centrally located complete documentation in many consistent easy to
read formats, of the system and *ALL* API's, including in-line tutorials
and examples.
- Data types like 'ENUM' which appeal to ametures.
- There are no administrative mandatorys. Eg, VACUUM. (A stand-alone
commercial app, like an Email client, will be contrainted by having to
be an app and a DBA in one.)
- The tables (not innodb) are in different files of the same name.
Allowing the OS adminitrator great ability. EG, putting tables on
separate partitions and therefore greatly speeding performance.
- They have extensive backup support. Including now, concurrent backup
without user interuption or risk of inconsistency.
Now I have begun to climb the ladder a bit, I know this it of little
importance compared to working referential constraints, triggers,
procedures and transactions... You also have the excelent mailing list
'novice', with excelent support for Ametures, with the most friendly
welcome note: 'No problem too minor'! Thanks to you all for providing
the system I am now beginning to enjoy using.
PS: I like the '\dt'. Especially the way it can be used half way
through a true statement, inspired bit of genious there.
Ben
Hi Ben
-----Original Message-----
From: Ben Clewett [mailto:B.Clewett@roadrunner.uk.com]
Sent: 17 April 2003 10:45
Cc: pgsql-hackers@postgresql.org
Subject: [HACKERS] For the ametures. (related to "Are we
losing momentum?")I am not a hacker of PgSQL, and new to Databases. I was using MySQL
under .NET, but was annoyed by their agressive licence agreements and
immaturity. (Their sales personel are also very rude. One girl once
told me that if I didn't like their licence terms I should just use
flat-files instead.)
Probably more powerful ;-)
- A true Windows version which people can learn their craft on.
Coming with 7.4...
- Tools which look like Access, to do row level data
editing with no SQL.
It looks more like SQL Server's Enterprise Manager but does most if not
all of what I expect you need.
- Centrally located complete documentation in many
consistent easy to
read formats, of the system and *ALL* API's, including
in-line tutorials
and examples.
The tarball includes the complete documentation in HTML format, and in
pgAdmin there's a searchable copy in the main chm help file.
- Data types like 'ENUM' which appeal to ametures.
Isn't that just syntactic sugar for a column with a check for specific
values on it?
- There are no administrative mandatorys. Eg, VACUUM.
(A stand-alone
commercial app, like an Email client, will be contrainted by
having to
be an app and a DBA in one.)
PostgreSQL is by no means alone in this requirement. SQL Server for
example has 'optimizations' that are performed usually as part of a
scheduled maintenance plan and are analagous to vacuum in some ways.
- The tables (not innodb) are in different files of the
same name.
Allowing the OS adminitrator great ability. EG, putting tables on
separate partitions and therefore greatly speeding performance.
One reason for not doing this is that a table in PostgreSQL might span
mutiple files if it exceeds a couple of gigs in size.
- They have extensive backup support. Including now,
concurrent backup
without user interuption or risk of inconsistency.
So does PostgreSQL (pg_dump/pg_dumpall).
Regards, Dave
PS, it's nice you decided not to go to the Dark Side :-)
Import Notes
Resolved by subject fallback
Hi Dave,
A brief defence of my posting. After which I'll retire to my side of
the fence :)
- A true Windows version which people can learn their craft on.
Coming with 7.4...
I look forward to this greatly. Maybe here I'll have the chance to fix
some problems for the greater community.
- Tools which look like Access, to do row level data
editing with no SQL.It looks more like SQL Server's Enterprise Manager but does most if not
all of what I expect you need.
Sorry, my fault, an excellent program.
The tarball includes the complete documentation in HTML format, and in
pgAdmin there's a searchable copy in the main chm help file.
But not the API's. Not in one central location. Some of it, the stuff
I use, is on GBorg, and in inconsistent format. I have personally found
some documentation very fragmented. So a subtle point about an ability
is lost as I have assumed all comments to be in a few pages, and missed
something vital or relevent in another sourse. Eg, see my comment at
the end. But it's better than msdn :)
- Data types like 'ENUM' which appeal to ametures.
Isn't that just syntactic sugar for a column with a check for specific
values on it?
Yes :) By point is not that PostgreSQL is lacking, only that the
ameture finds others more friendly and inviting.
Although this may be a point which is irrelevent?
My personal 'gripe' was when reading through the postings, some people
considered people who have not the time, patience or ability, to learn
PostgreSQL completelly, somehow not worthy.
I wanted to support us dumb users! :)
- There are no administrative mandatorys. Eg, VACUUM.
(A stand-alone
commercial app, like an Email client, will be contrainted by
having to
be an app and a DBA in one.)PostgreSQL is by no means alone in this requirement. SQL Server for
example has 'optimizations' that are performed usually as part of a
scheduled maintenance plan and are analagous to vacuum in some ways.
Is this a weekness in DBMS's that don't require this? (MySQL, Liant
etc.) Is there a way of building a guarbage collector into the system?
My Windows PC has no 'cron'.
- The tables (not innodb) are in different files of the
same name.
Allowing the OS adminitrator great ability. EG, putting tables on
separate partitions and therefore greatly speeding performance.One reason for not doing this is that a table in PostgreSQL might span
mutiple files if it exceeds a couple of gigs in size.
They used multile files for tables, with a common pefix of the table
name. But they have dropped this them selves now.
I miss the way with MySQL I could delete a table, or move it, or back it
up, manually using 'rm', 'mv' or 'cp'.
Working with IDE drives on PC's, you can double the performace of a DB
just by putting half the tables on a disk on another IDE chain. Adding
a DB using 'tar' is very a powerful ability.
But hay, if I missed it that much, I would not have moved! :)
- They have extensive backup support. Including now,
concurrent backup
without user interuption or risk of inconsistency.So does PostgreSQL (pg_dump/pg_dumpall).
I have used this, and it's a great command.
I could not work out from the documentation whether it takes a snapshot
at the start time, or archives data at the time it find's it. The
documentation (app-pg-dump.html). As the documentation does not clarify
this very important point, I desided it's not safe to use when the
system is in use.
Can this command can be used, with users in the system making heavy
changes, and when takes many hours to complete, does produce a valid and
consistent backup?
If so, you have all MySQL has here and in a more useful format.
PS, it's nice you decided not to go to the Dark Side :-)
Thanks, Ben
On Thursday 17 April 2003 13:44, Ben Clewett wrote:
Hi Dave,
A brief defence of my posting. After which I'll retire to my side of
the fence :)
(snip)
- Data types like 'ENUM' which appeal to ametures.
Isn't that just syntactic sugar for a column with a check for specific
values on it?Yes :) By point is not that PostgreSQL is lacking, only that the
ameture finds others more friendly and inviting.Although this may be a point which is irrelevent?
Probably ;-) because MySQL too lacks a few "user friendly" features
(like boolean datatypes).
Ian Barwick
barwick@gmx.net
(please note that the word is "amateur" - it comes from French/Latin,
meaning people who do things for the love of it).
There are lots of cron clones for Windows - try a Google search.
Also, there is a native Windows port of Pg 7.2.1 available - we have been
using it for a couple of months now on a small project without a single
hitch. Search this mailing list for details.
Like you, we eagerly await the official Windows port in 7.4. (then we'll
have shema, for example).
Part of the problem that amateurs often face in dealing with things like a
DBMS is that their lack of formal training leads them to expect things to
work in some intuitive fashion, and they don't (for very good technical
reasons). As someone who in a past life had to teach relational theory and
practice, I can tell you that just getting across the idea of a Cartesian
product can be quite hard. And as a former DBA I can tell you that even
seasoned professional developers often don't/can't take the trouble to
analyse what their queries are doing and why they demand so much in
resources. Running a DBMS (*any* DBMS) which has significant requirements is
unfortunately something that requires both understanding and experience. It
never "just works".
Finally, one of the important things for my particular situation, is that Pg
comes with a BSDish license, which means we have no issues with bundling it.
AFAIK it's pretty much alone in that.
andrew
----- Original Message -----
From: "Ben Clewett" <B.Clewett@roadrunner.uk.com>
To: "Dave Page" <dpage@vale-housing.co.uk>; <pgsql-hackers@postgresql.org>
Sent: Thursday, April 17, 2003 7:44 AM
Subject: Re: [HACKERS] For the ametures. (related to "Are we losing
momentum?")
Show quoted text
Hi Dave,
A brief defence of my posting. After which I'll retire to my side of
the fence :)- A true Windows version which people can learn their craft on.
Coming with 7.4...
I look forward to this greatly. Maybe here I'll have the chance to fix
some problems for the greater community.- Tools which look like Access, to do row level data
editing with no SQL.It looks more like SQL Server's Enterprise Manager but does most if not
all of what I expect you need.Sorry, my fault, an excellent program.
The tarball includes the complete documentation in HTML format, and in
pgAdmin there's a searchable copy in the main chm help file.But not the API's. Not in one central location. Some of it, the stuff
I use, is on GBorg, and in inconsistent format. I have personally found
some documentation very fragmented. So a subtle point about an ability
is lost as I have assumed all comments to be in a few pages, and missed
something vital or relevent in another sourse. Eg, see my comment at
the end. But it's better than msdn :)- Data types like 'ENUM' which appeal to ametures.
Isn't that just syntactic sugar for a column with a check for specific
values on it?Yes :) By point is not that PostgreSQL is lacking, only that the
ameture finds others more friendly and inviting.Although this may be a point which is irrelevent?
My personal 'gripe' was when reading through the postings, some people
considered people who have not the time, patience or ability, to learn
PostgreSQL completelly, somehow not worthy.I wanted to support us dumb users! :)
- There are no administrative mandatorys. Eg, VACUUM.
(A stand-alone
commercial app, like an Email client, will be contrainted by
having to
be an app and a DBA in one.)PostgreSQL is by no means alone in this requirement. SQL Server for
example has 'optimizations' that are performed usually as part of a
scheduled maintenance plan and are analagous to vacuum in some ways.Is this a weekness in DBMS's that don't require this? (MySQL, Liant
etc.) Is there a way of building a guarbage collector into the system?
My Windows PC has no 'cron'.- The tables (not innodb) are in different files of the
same name.
Allowing the OS adminitrator great ability. EG, putting tables on
separate partitions and therefore greatly speeding performance.One reason for not doing this is that a table in PostgreSQL might span
mutiple files if it exceeds a couple of gigs in size.They used multile files for tables, with a common pefix of the table
name. But they have dropped this them selves now.I miss the way with MySQL I could delete a table, or move it, or back it
up, manually using 'rm', 'mv' or 'cp'.Working with IDE drives on PC's, you can double the performace of a DB
just by putting half the tables on a disk on another IDE chain. Adding
a DB using 'tar' is very a powerful ability.But hay, if I missed it that much, I would not have moved! :)
- They have extensive backup support. Including now,
concurrent backup
without user interuption or risk of inconsistency.So does PostgreSQL (pg_dump/pg_dumpall).
I have used this, and it's a great command.
I could not work out from the documentation whether it takes a snapshot
at the start time, or archives data at the time it find's it. The
documentation (app-pg-dump.html). As the documentation does not clarify
this very important point, I desided it's not safe to use when the
system is in use.Can this command can be used, with users in the system making heavy
changes, and when takes many hours to complete, does produce a valid and
consistent backup?If so, you have all MySQL has here and in a more useful format.
PS, it's nice you decided not to go to the Dark Side :-)
Thanks, Ben
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-----Original Message-----
From: Ben Clewett [mailto:B.Clewett@roadrunner.uk.com]
Sent: 17 April 2003 12:44
To: Dave Page; pgsql-hackers@postgresql.org
Subject: Re: [HACKERS] For the ametures. (related to "Are we
losing momentum?")But not the API's. Not in one central location. Some of it,
the stuff
I use, is on GBorg,
The API's that ship with the source (libpq et al.) are all documented in
the HTML docs that ship with the code as far as I'm aware.
I suspect what you look at on Gborg will be one or more of psqlODBC,
Npgsql or libpqxx? These are seperate projects, and hence have their own
documentation. I don't know about libpqxx, but the psqlODBC docs are
very old I admit. If anyone cares to work on them, please let me know.
The Npgsql stuff is all very new and very alpha and I guess of all the
Npgsql hackers, I'm probably the only one who hangs around here - that's
how seperate the project is from PostgreSQL itself.
What we could probably use is a page on the main website highlighting
all the programming interfaces - similar to
http://www.postgresql.org/users-lounge/interfaces.html but a bit more
prominent and focused. I'll put my third hat on now and repeat - if
anyone cares to work on this, please let me know :-)
My personal 'gripe' was when reading through the postings,
some people
considered people who have not the time, patience or ability,
to learn
PostgreSQL completelly, somehow not worthy.I wanted to support us dumb users! :)
That's certainly not the case for many of the people here, though you
must remember, the vast majority of us work voluntarily and prefer to
help users who have made an effort to help themselves first rather than
those who expect us to do everything for them for free. Thankfully those
people are few and far between, but they do crop up from time to time.
PostgreSQL is by no means alone in this requirement. SQL Server for
example has 'optimizations' that are performed usually as part of a
scheduled maintenance plan and are analagous to vacuum in some ways.Is this a weekness in DBMS's that don't require this? (MySQL, Liant
etc.) Is there a way of building a guarbage collector into
the system?
Potentially I guess, if they are cleaning up and trying to reuse space
on the fly then they could suffer a performance hit.
My Windows PC has no 'cron'.
No, but it probably has a Scheduled Tasks folder unless it's a really
old version.
Can this command can be used, with users in the system making heavy
changes, and when takes many hours to complete, does produce
a valid and
consistent backup?
Yes, pg_dump will give you a consistent backup - this is from section
9.1 of the Administrators Guide in the Backup and Restore section:
Dumps created by pg_dump are internally consistent, that is, updates to
the database while pg_dump is running will not be in the dump. pg_dump
does not block other operations on the database while it is working.
(Exceptions are those operations that need to operate with an exclusive
lock, such as VACUUM FULL.)
Regards, Dave.
Import Notes
Resolved by subject fallback
On Thu, Apr 17, 2003 at 11:44:07AM +0000, Ben Clewett wrote:
I miss the way with MySQL I could delete a table, or move it, or back it
up, manually using 'rm', 'mv' or 'cp'.
Under most circumstances, you can't do that _anyway_, because doing
so will break stuff unless the postmaster is stopped. I agree that
bing able to put tables and files on their own platters would be a
Good Thing, but in order to make it really safe, it needs to be
managed by the postmaster. Making this difficult is sort of a
defence mechanism, therefore: if you make it too easy, people will be
shooting themselves in the foot all the time.
A
--
----
Andrew Sullivan 204-4141 Yonge Street
Liberty RMS Toronto, Ontario Canada
<andrew@libertyrms.info> M2P 2A8
+1 416 646 3304 x110Ben Clewett <B.Clewett@roadrunner.uk.com> writes:
- The tables (not innodb) are in different files of the same name.
Allowing the OS adminitrator great ability. EG, putting tables on
separate partitions and therefore greatly speeding performance.
FWIW, we used to do it that way too, many releases ago. We gave it up
because it was impossible to support rollback of table deletion/rename
with that storage rule underneath. Consider
BEGIN;
DROP TABLE a;
CREATE TABLE a (with-some-other-schema);
-- oops, think better of it
ROLLBACK;
With table files named after the table, we could not support the above,
because we'd need two "a"'s in existence at the same time. Postgres'
catalog mechanisms can handle rollback of the catalog changes, but the
Unix filesystem never heard of rollback :-(
There are other reasons, which some folks have pointed out elsewhere in
this thread, but that was the killer one.
I notice that MySQL seems to be migrating in this direction as well...
regards, tom lane
Dave Page wrote:
- They have extensive backup support. Including now,
concurrent backup
without user interuption or risk of inconsistency.So does PostgreSQL (pg_dump/pg_dumpall).
I have applied the following doc patch to the pg_dump documentation to
more clearly state that it can do consistent backups during concurrent
access --- too many people weren't seeing that capability.
--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073
