Subject: Re: Why mention to Oracle ?

From: Marcos Pegoraro <[email-masked]>
Date: Fri, 20 Sep 2024 17:26:49 -0300

Em sex., 20 de set. de 2024 às 15:11, Tomas Vondra <[email-masked]>
escreveu:

> IMHO it's quite reasonable to say "we do X, but this other product
> (which is what we try to mimic) does Y".
>

Ok, for Data Type Formatting Functions is fine, if they were really copied
from, but the others ...
Bug Reporting Guidelines, LOCK, SELECT, ROLLBACK TO SAVEPOINT and CURSORS

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From: "Jonah H. Harris" <[email-masked]>
Date: Fri, 20 Sep 2024 17:34:06 -0400

> Bug Reporting Guidelines, LOCK, SELECT, ROLLBACK TO SAVEPOINT and CURSORS

Seems to me this has already been answered well multiple times by multiple
people; I’m not sure why this is such an issue, or one that warrants
continued discussion.

By your own admission, you wouldn’t see the value, where others who came
from Oracle would. Additionally, your assumption is incorrect: many Oracle
databases are migrated to Postgres, more-so today than when much of that
was written.

You’re arguing against it being in the docs and talking about how much
better it would be in other more focused content, which does have some
merit. But, at the same time, you’re neither qualified nor volunteering to
write it. As such, getting rid of it here serves what purpose other than
omitting useful information to those it would benefit directly in the
documentation?

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From: Marcos Pegoraro <[email-masked]>
Date: Sat, 21 Sep 2024 13:50:37 -0300

> people; I’m not sure why this is such an issue, or one that warrants

No, I do not want to continue a discussion about a closed issue, I just
want to improve DOCs, or get it cleaner, just that.

https://www.postgresql.org/docs/current/sql-lock.html
PostgreSQL lock modes and the LOCK TABLE syntax are compatible with those
present in Oracle.

https://www.postgresql.org/docs/current/sql-rollback-to.html
The SQL standard specifies that the key word SAVEPOINT is mandatory, but
PostgreSQL and Oracle allow it to be omitted.

https://www.postgresql.org/docs/current/sql-select.html
Applications written for Oracle frequently use a workaround involving the
automatically generated rownum column, which is not available in
PostgreSQL, to implement the effects of these clauses.

https://www.postgresql.org/docs/current/plpgsql-cursors.html
FOR can be replaced by IS for Oracle compatibility.

So, except for Data Type Formatting, because Postgres mimics Oracle version,
and converting to PL/pgSQL, these other cases, and I don't know if other
exists, the DOC says something that is specific to a database, so users
which come from any other database could ask why not their database
compatibility is shown too. So I think all these cases could be removed.

> databases are migrated to Postgres, more-so today than when much of that

I didn't say no more people are migrating from Oracle, I just say that
maybe migrations are now coming from other databases, like SQL Server,
MySQL, DB2, Firebird, Mongo and many others. So why do you document only
for those which come from Oracle ?
New Postgres users are today 90% coming from Oracle or 10%, I think we
cannot have this number exactly. And if nobody knows, why mention any of
them ?

Thanks for your time and I repeat, I just want to get Postgres DOCs better,
just that.

regards
Marcos

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From: Bruce Momjian <[email-masked]>
Date: Sat, 21 Sep 2024 17:42:18 -0400

On Sat, Sep 21, 2024 at 01:50:37PM -0300, Marcos Pegoraro wrote:
> I didn't say no more people are migrating from Oracle, I just say that maybe
> migrations are now coming from other databases, like SQL Server, MySQL, DB2,
> Firebird, Mongo and many others. So why do you document only for those which
> come from Oracle ?
> New Postgres users are today 90% coming from Oracle or 10%, I think we cannot
> have this number exactly. And if nobody knows, why mention any of them ?
> 

I suggest you explain what changes would make the docs better (meaing
more useful).

-- 
  Bruce Momjian  <[email-masked]>        https://momjian.us
  EDB                                      https://enterprisedb.com

  When a patient asks the doctor, "Am I going to die?", he means 
  "Am I going to die soon?"

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From: Marcos Pegoraro <[email-masked]>
Date: Sun, 22 Sep 2024 11:09:30 -0300

> I suggest you explain what changes would make the docs better (meaing

Well, I think I already did this in this discussion.
Tom said that some functions were copied from Oracle, so it is ok to
mention them. I don't think so.
Tomas said that we can mention other vendors, even if others don't do the
same for us. I don't think so again.
But David answered that would be cool if we create a separate
page/wiki/tool which compares, translates or anything like that to other
databases.
So, if we have a "Compatibility/Translation/Feature Comparison/ ... with
other Databases", it would be so cool.
But we don't have this kind of page, so why do we need to mention just one
of them ?
Searching on SGML there are 0 mentions to SQL Server and MySQL, but there
are almost 50 mentions to Oracle.
So this is my point, if you don't do the same for others, why do it for
Oracle ?

And again, I'm not saying that migrations from Oracle are not important,
I'm saying migrations from Oracle have the same importance than from MySQL,
SQL Server, Mongo, ...

regards
Marcos

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From: Roberto Mello <[email-masked]>
Date: Sun, 22 Sep 2024 09:48:38 -0600

> But we don't have this kind of page, so why do we need to mention just one

Because people contributed those.

> So this is my point, if you don't do the same for others, why do it for

Because people contributed those.

> I'm saying migrations from Oracle have the same importance than from MySQL,

Again, different people at different times felt it was important to
contribute patches to the documentation
explaining Oracle differences, or porting, etc. That's why those are in the
current docs.

If you're volunteering to add a MySQL, SQL Server, Mongo, etc porting to
the docs, I'm sure it could be a
nice addition.

Roberto

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From: Marcos Pegoraro <[email-masked]>
Date: Tue, 24 Sep 2024 12:59:26 -0300

> the docs, I'm sure it could be a

And if we create a page like https://www.postgresql.org/about/featurematrix/
But instead of Postgres versions we have other vendors.
Every feature would have a Postgres way of doing and what differs from his
old database.
Feature PostgreSQL Oracle SQL Server MySQL Firebird
SELECT  N ROWS LIMIT 10   TOP 10   FIRST 10
CONCAT STRINGS 'Name: ' || Name    'Name: ' + Name
REBUILD INDEX REINDEX ALTER INDEX… REBUILD
CURRENT DATE CURRENT_DATE   GETDATE
This is just an example, for sure there would be several tables, for DMLs,
for DDL, for Maintenance ...

What do you think ?

regards
Marcos

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From: Greg Sabino Mullane <[email-masked]>
Date: Wed, 25 Sep 2024 08:35:35 -0400

> And if we create a page like
> https://www.postgresql.org/about/featurematrix/

This sounds like something that would fit well on the Postgres wiki:

https://wiki.postgresql.org/

Cheers,
Greg