473,889 Members | 1,391 Online
Bytes | Software Development & Data Engineering Community
+ Post

Home Posts Topics Members FAQ

Is my MySQL Gaining ?

Dear all,

Their was a huge rore about MySQL recently for something in java functions
now theirs one more

http://www.mysql.com/doc/en/News-5.0.x.html

Does this concern anyone.

What I think is PostgreSQL would have less USP's (Uniqe Selling Points
though we dont sell) now.

What do you think yes we PostgreSQL users need some introspection.

Regards,
Vishal Kashyap.

---------------------------(end of broadcast)---------------------------
TIP 5: Have you checked our extensive FAQ?

http://www.postgresql.org/docs/faqs/FAQ.html

Nov 12 '05
175 11562
El Mar 30 Dic 2003 04:07, B. van Ouwerkerk escribió:
Does it say that there is a limit? Yes surely there is one, which most
likely will depends on the Processor and OS you are running (64 bit or 32
bit), but anyway, such log varchars wouldn't be that recommended, and
maybe the TEXT data type would be more suitable.


If you are used to MySQL you're used to a maximum limit because of MySQL
will set a limit.
This kind of information is interesting if you're trying to understand
PostgreSQL.


Well, maybe it's because I read some mails from Tom Lane discussing how
optimal varchar(300000) would be. :-)

--
09:25:01 up 34 days, 15:41, 2 users, load average: 0.05, 0.30, 0.38
-----------------------------------------------------------------
Martín Marqués | select 'mmarques' || '@' || 'unl.edu.ar'
Centro de Telematica | DBA, Programador, Administrador
Universidad Nacional
del Litoral
-----------------------------------------------------------------
---------------------------(end of broadcast)---------------------------
TIP 1: subscribe and unsubscribe commands go to ma*******@postg resql.org

Nov 12 '05 #131

If you have no control over the running postmasters, then where the
files are stored gives you no advantage at all either
for backup or security. Backing up physical files while the postmaster
running is asking for it; this is explained every three days
or so on the lists. (that should be part of some consent form for using
PG...'I acknowledge that copying physical files while
the postmaster is running is ineffective, will get me in trouble, and
promote both moral degradation and tooth decay. Please don't ask.').

As for security...the data cluster is created with 700 permissions,
owned by the postgres super-user, and the postmaster will not
even start up if the directory permissions are set otherwise.

Personally, I wouldn't trust a sysad/dba at an ISP who gave me
sufficient rights to create, say, Oracle tablespaces willy-nilly. That
would fit your
example of lazy and lax administration. (Apologies for using the 'O'
word...)

We're back into the mindset of an RDBMS being thought of as some sort
of FoxPro-on-steroids thing. That is not what Postgres, Oracle,
Sybase, etc. are.

On Dec 30, 2003, at 5:40 AM, Bret Busby wrote:
On Tue, 30 Dec 2003, Tom Lane wrote:
Date: Tue, 30 Dec 2003 02:07:23 -0500
From: Tom Lane <tg*@sss.pgh.pa .us>
To: Bret Busby <br**@busby.net >
Cc: pg***********@p ostgresql.org, pg***********@p ostgresql.org
Subject: Re: [GENERAL] Is my MySQL Gaining ?

Bret Busby <br**@busby.net > writes:
Does PostgreSQL yet allow the user or programmer, to determine where
the
database will be stored?


You speak as though you think that would be a good idea.

In my mind, "where the database is stored" is not a matter for users,
nor for programmers, but for DBAs --- that is, the grunts who have to
worry about backup policies and suchlike. This is not an issue that
should be exposed at the SQL-command level, and therefore it does not
concern either users or database programmers.

That's not to say that we don't have work to do here. There's
considerable interest in developing "tablespace " features to help the
DBA manage his problems. But I absolutely will not buy into any
suggestion that user foo's tables must be stored in user foo's home
directory (even if I thought that Postgres user foo must correspond
to a local Unix user foo ... which I don't ...)

regards, tom lane


This is where terminology becomes amusing.

I meant the OS user, not the DBMS user, and I am not suggesting that
DBMS users should be able to set where their tables are stored.

All kinds of scenarios can arise; where the DBA and the developer are
the same person, or, employed in the same department of the same
company; where the DBA is employed by the company, and the developer is
a contractor, or an employee of a contractor, and, as I previosuly
mentioned, the scenario where an ISP, by hosting a web site with a
database backend, has a database in the same holding area as is held
all
the databases of all of the ISP's clients who similarly have web sites
with database backends.

I would feel more confident about having a personal database "on the
Internet"; a backend to my web site, if I knew that the database wasn't
thrown into the same storage area as everyone of the ISP's other
account
holders, who also have the same DBMS database backends to their web
sites. You never know what else is sharing the same storage area, or
how
safe your database is in there. It is a bit like having a cat; I would
rather that the cat is with me, and that I know where it is, and what
is
happening with the cat, than having the cat locked away in a common
room
for all cats. Also, using that analogy, if I decide to move away with
my
cat, if it is with me, it is much simpler, and, cleaner, for me to
simply pick up the cat and take it with me, than to try to find all of
its bits, in a common room full of other cats. If I have a database
system hosted by an ISP, and I try to move it to another ISP, surely,
it
would be simpler and cleaner, if I know that the database is stored in
or under my home directory with the ISP, than having the database
stored
in a central repository with all of the other accounts holders'
databases.

There is also the issue of security, in the same context; I would feel
much more secure, with a database hosted by an ISP, if I could control
the privileges on the database directory, rather than allowing the ISP
the control. Having been a user on various UNIX systems, I have seen
some pretty lax security by systems administrators, and other users,
and
I am reminded of a senior university computing lecturer, who had the
exam for an advanced computing unit, with such lax security that some
students wandering through the system, found the exam, and, when they
sat the exam, were surprisingly well prepared (no, I was not one of the
students), resulting in all the students in the unit, having to re-sit
the exam, and, other effects. A DBA should be able to control where a
database is stored, and the level of security applicable to where the
database is stored (privileges applicable to the directory, etc), and,
as I have previously mentioned, it can occur that the DBA and the
developer/programmer, are the same person.

As an example, on a personal basis, if I ever get the number of names
in
my genealogy system, up to around 10,000, I would really want, if using
a database backend (which would, I believe, be required), to have
control over where the data is stored, so that I can easily and
reliably
back it up, as such data can be unreplaceable, and can take decades to
accumulate.

Similarly, for commercial databases, now that DVD's are writable,
backing up a largish database, using OS backing up, would be much
better, and moreso, witth the data for a database, stored where it is
wanted.

I am not sure whether it can all be done with symbolic links, to place
PostgreSQL databases where a (OS, not DBMS) user or developer or DBA
wants them to be stored, but I suggest that provision should exist for
a
person to determine where the person's (as owner of the database)
database file(s) exist, for security, backing up, etc.

--
Bret Busby
Armadale
West Australia
..............

"So once you do know what the question actually is,
you'll know what the answer means."
- Deep Thought,
Chapter 28 of
"The Hitchhiker's Guide to the Galaxy:
A Trilogy In Four Parts",
written by Douglas Adams,
published by Pan Books, 1992
............... ............... ............... .......
---------------------------(end of
broadcast)---------------------------
TIP 1: subscribe and unsubscribe commands go to
ma*******@postg resql.org

--------------------

Andrew Rawnsley
President
The Ravensfield Digital Resource Group, Ltd.
(740) 587-0114
www.ravensfield.com
---------------------------(end of broadcast)---------------------------
TIP 8: explain analyze is your friend

Nov 12 '05 #132
Personally I think that the docs are great (especially so with 7.4). Of
course they are aimed at experienced admins, so it is easier to find things
if you have a basic understanding of the RDBMS to start with. Of course
things can always be improved, but I am opposed to adding cruft to the core
documentation. Let's keep these things friendly towards experienced users
so that we can WORK efficiently.

However, Ericson does have a point, that the docs are NOT adequate if you
are new to PostgreSQL and have only used MySQL or MS Access. There have
been many ideas on how to resolve this issue, but I say that it should be
resolved outside the core docs. The example of Python has been used, with
an in-depth tutorial separate from the main docs. That way, an experienced
user can discard the tutorial.

I have argued elsewhere that a separate curriculum should be maintained, but
I also understand that that will not happen overnight. My suggestion at the
moment is to break the tutorial off so that it is not part of the main docs
(I am not satisfied that it is large enough to really fill its purpose) and
maintain it separately. I would then look at how to improve the tutorial.

Hint out there to Ericson and others. The Reference Manual section of SQL
commands is the part of the manual I use most. Procedural language sections
also are used much around here :-)

Best Wishes,
Chris Travers
---------------------------(end of broadcast)---------------------------
TIP 2: you can get off all lists at once with the unregister command
(send "unregister YourEmailAddres sHere" to ma*******@postg resql.org)

Nov 12 '05 #133
From: "B. van Ouwerkerk" <bv*@atz.nl>:
I still don't find it. I know you can do a varchar(255) but what is the
maximum PG will allow? Is there a maximum?
In short, how much can I put into the field before it breaks.
It is not in the manual because in this case it probably doesn't matter.
Check the FAQ. I believe that the maximum in a field in around 1GB. More
text than I have to store ;-) This is more of a backend-related issue, and
perhaps the limits could be handled in the introduction of the datatypes
section.
I know a fair bit of SQL, just wanne know more about PG. Next year I will
start shopping at the nearest bookstore to see what they have on PG..
Hopefully there is a book that compares to the book MySQL but then for

PG..

Look for Bruce's book.

Best Wishes,
Chris Travers
---------------------------(end of broadcast)---------------------------
TIP 1: subscribe and unsubscribe commands go to ma*******@postg resql.org

Nov 12 '05 #134
At 20:00 30-12-2003 +0700, Chris Travers wrote:
Personally I think that the docs are great (especially so with 7.4). Of
course they are aimed at experienced admins, so it is easier to find things
if you have a basic understanding of the RDBMS to start with. Of course
things can always be improved, but I am opposed to adding cruft to the core
documentatio n. Let's keep these things friendly towards experienced users
so that we can WORK efficiently.


IMO you can have both. How much would it hurt if there was a bit more
information? Or a link to a related topic (as someone else suggested before).

If I think about using a certain PHP function I might want to double check
on the exact syntax or to look at the minimum version required. So I go to
the PHP.net website and quickly look at it.. but a newcomer might spend
quite some time on the same page..
The same could become true for the PostgreSQL docs I gues. Meaning I will
read a bit longer on the same page then you. But only until I have
assimilated the information..

All I would ask is a bit more information in the docs then found at
present, add information where it currently stops without talking to much :-)

I'm quite sure there are enough knowledgeable persons around to fill in the
gaps found at present. But perhaps the interactive version of the docs
might serve a great perpose here.
B.
---------------------------(end of broadcast)---------------------------
TIP 2: you can get off all lists at once with the unregister command
(send "unregister YourEmailAddres sHere" to ma*******@postg resql.org)

Nov 12 '05 #135
"Bret Busby" <br**@busby.net > Wrote:
On Sat, 27 Dec 2003, Chris Travers wrote:
In short, I do not see MySQL as any sort of threat to PostgreSQL, near or long-term. PostgreSQL will continue when MySQL no longer exists. Firebird is a more serious competitor long-term, though I found it to be hard to
learn when compared to PostgreSQL. It has a long way to go before being as easy to use as PostgreSQL.
I suggest that it is a bit premature, to suggest that MySQL will
disappear, and that PostgreSQL will still exist.

Ok, fair enough, and since it is GPL'd when it is no longer maintained, it
will still exist ;-). One of the things that makes MySQL different than,
say, Nautilus is the fact that you have client libs licensed under the GPL.
Unless MySQL AB decides to change this, we will have a strong advantage, and
I don't see this changing anytime soon.

But I still think that MySQL is more likely to become non-viable than
PostgreSQL... MySQL is not helping their case much (now that PHP will not
enable MySQL by default anymore due to licensing issues).
Each does have its advantages, and, people develop things in parallel in
the two different systems.
I have developed systems that support both. I understand what you mean.

For example, on the perl-gedcom list, people have developed, in
parallel, genealogy database systems that they use, some using MySQL,
some using PostgreSQL. People have their preferences, as some still use
(or require to be used) MS Access, or Foxpro, or SQL-Server, or
Informix, etc.

Does PostgreSQL yet allow the user or programmer, to determine where the
database will be stored?


I think you mean DBA rather than user or programmer. Tablespaces are in the
works and will allow finer tuning of database storage.

Best Wishes,
Chris Travers
---------------------------(end of broadcast)---------------------------
TIP 6: Have you searched our list archives?

http://archives.postgresql.org

Nov 12 '05 #136
On Mon, Dec 29, 2003 at 23:41:22 -0000,
John Sidney-Woollett <jo****@wardbro ok.com> wrote:
Actually, sometimes these questions will be postgres specific, and this is
where the docs are too light.

An example is an update statement using values from a correlated subquery.
Here's example code in pgsql:

update PHOTO.WPImage
set WPImageStateID = 3,
Width = WPImageHeader.W idth,
Height = WPImageHeader.H eight,
ContentType = WPImageHeader.C ontentType,
ContentLength = WPImageHeader.C ontentLength
where WPImage.WDResou rceID = WPImageHeader.W DResourceID
and WPImage.WDResou rceID = pResourceID
and WPImage.WPSizeT ypeID = 0;

In Oracle this might be written:

update PHOTO.WPImage i
set WPImageStateID = 3,
(Width, Height, ContentType, ContentLength) = (
select Width, Height, ContentType, ContentLength
from PHOTO.WPImageHe ader ih
where ih.WDResourceID = i.WDResourceID)
where WPImage.WDResou rceID = pResourceID
and WPImage.WPSizeT ypeID = 0;

You'll notice that the syntax is entirely different, and very relevant for
inclusion in the docs for each database's update statement.
The Postgres example uses a join instead of subselects. You could have
used subselects in postgres, but because there is currently not a way
to set more than one column at a time from one subselect, you would
have to repeat the subselect 4 times.

I am not convinced that this needs to be documented in the section on
the update statement. This is something that would belong in an oracle
to postgres conversion guide.
I've mentioned it before but here it is again, contrast this explanation
of the UPDATE command in postgres with Oracle's explanation. Which one
would explain how to make use of a correlated subquery without resorting
to more googling or the list?

postgres: http://www.postgres.org/docs/current...ql-update.html

Oracle: http://miami.int.gu.edu.au/dbs/7016/...7a.htm#2067717

My point is not so much that the docs are difficult for newbies (and they
probably are), but that they just lack sufficient meat which really ought
to be included.


I still don't see that there needs to be a lot more added to the postgres
update command documentation. The main thing missing is links to the
syntax definitions for things like from list, condition and expression.
Currently you just have to know that the syntax for from items and conditions
is described with the select documentation and that expression syntax is
covered in the value expressions chapters under sql syntax.

---------------------------(end of broadcast)---------------------------
TIP 5: Have you checked our extensive FAQ?

http://www.postgresql.org/docs/faqs/FAQ.html

Nov 12 '05 #137

rw****@averillp ark.net says...
Check http://firebird.sourceforge.net/
note that Firebird (the Interbase spinoff) used the name before
Firebird (the Mozilla spinoff) did.

The Mozilla people have undertaken to change this, but are dragging
their feet, much to the disgust of the real Firebirders.
Paul...
richard


--
plinehan y_a_h_o_o and d_o_t com
C++ Builder 5 SP1, Interbase 6.0.1.6 IBX 5.04 W2K Pro
Please do not top-post.

"XML avoids the fundamental question of what we should do,
by focusing entirely on how we should do it."

quote from http://www.metatorial.com
---------------------------(end of broadcast)---------------------------
TIP 4: Don't 'kill -9' the postmaster

Nov 12 '05 #138


jo****@wardbroo k.com says...

As long time Oracle developer recently converted to Postgres, I think that
you would all do better to use Oracle as your benchmark instead of MySQL.

<... Theme development snipped>
Very good post and point!
Paul...
--
plinehan y_a_h_o_o and d_o_t com
C++ Builder 5 SP1, Interbase 6.0.1.6 IBX 5.04 W2K Pro
Please do not top-post.

"XML avoids the fundamental question of what we should do,
by focusing entirely on how we should do it."

quote from http://www.metatorial.com
---------------------------(end of broadcast)---------------------------
TIP 4: Don't 'kill -9' the postmaster

Nov 12 '05 #139
RE "The main thing missing is links to the syntax definitions for things
like from list, condition and expression. Currently you just have to know
that the syntax for from items and conditions is described with the
select documentation and that expression syntax is covered in the value
expressions chapters under sql syntax."

Actually just having the links would be a great help (provided it took you
to the relevant section of the page rather than the start).

A fast full text index of the docs, and related material online would help
enormously - I see that something is in the pipline... Hooray!

John

Bruno Wolff III said:
On Mon, Dec 29, 2003 at 23:41:22 -0000,
John Sidney-Woollett <jo****@wardbro ok.com> wrote:
Actually, sometimes these questions will be postgres specific, and this is
where the docs are too light.
An example is an update statement using values from a correlated subquery.
Here's example code in pgsql:
update PHOTO.WPImage
set WPImageStateID = 3,
Width = WPImageHeader.W idth,
Height = WPImageHeader.H eight,
ContentType = WPImageHeader.C ontentType,
ContentLength = WPImageHeader.C ontentLength
where WPImage.WDResou rceID = WPImageHeader.W DResourceID
and WPImage.WDResou rceID = pResourceID
and WPImage.WPSizeT ypeID = 0;
In Oracle this might be written:
update PHOTO.WPImage i
set WPImageStateID = 3,
(Width, Height, ContentType, ContentLength) = (
select Width, Height, ContentType, ContentLength
from PHOTO.WPImageHe ader ih
where ih.WDResourceID = i.WDResourceID)
where WPImage.WDResou rceID = pResourceID
and WPImage.WPSizeT ypeID = 0;
You'll notice that the syntax is entirely different, and very relevant for
inclusion in the docs for each database's update statement.
The Postgres example uses a join instead of subselects. You could have

used subselects in postgres, but because there is currently not a way to
set more than one column at a time from one subselect, you would have to
repeat the subselect 4 times.
I am not convinced that this needs to be documented in the section on the update statement. This is something that would belong in an oracle
to postgres conversion guide.
I've mentioned it before but here it is again, contrast this explanation of the UPDATE command in postgres with Oracle's explanation. Which one would explain how to make use of a correlated subquery without
resorting to more googling or the list?
postgres:
http://www.postgres.org/docs/current...ql-update.html Oracle: http://miami.int.gu.edu.au/dbs/7016/...7a.htm#2067717
My point is not so much that the docs are difficult for newbies (and
they probably are), but that they just lack sufficient meat which really ought
to be included.
I still don't see that there needs to be a lot more added to the

postgres update command documentation. The main thing missing is links to the syntax definitions for things like from list, condition and expression.
Currently you just have to know that the syntax for from items and
conditions is described with the select documentation and that expression syntax is covered in the value expressions chapters under sql syntax.



---------------------------(end of broadcast)---------------------------
TIP 5: Have you checked our extensive FAQ?

http://www.postgresql.org/docs/faqs/FAQ.html

Nov 12 '05 #140

This thread has been closed and replies have been disabled. Please start a new discussion.

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.