Обсуждение: No documentation exists about ecpg ORACLE comptaible mode
Hi. (CCing Michael Meskes) One of my customers asked me about what oracle compatibility mode in ecpg means, and I noticed current documentation does not explain ecpg ORACLE compatible mode (ecpg -C ORACLE) in detail. I myself learned the feature of "-C ORACLE" from regression test (src/interfaces/ecpg/test/compat_oracle) and source code. Is lacking documentation intentional or do commit 3b7ab4380 and 3b9b7516f just forget adding the explanation? As for as I know, "ecpg -C ORACLE" is written briefly in ecpg command reference and PostgreSQL 11 release note, but they are not enougn information for users to understand feature of "ecpg -C ORACLE". https://www.postgresql.org/docs/current/app-ecpg.html ------------------------------- -C mode Set a compatibility mode. mode can be INFORMIX, INFORMIX_SE, or ORACLE. ------------------------------- https://www.postgresql.org/docs/11/release-11.html#id-1.11.6.21.5.9 ------------------------------- Add an ecpg mode to enable Oracle Pro*C-style handling of char arrays. This mode is enabled with -C. ------------------------------- On the other hand, informix compatible mode is written in detail. https://www.postgresql.org/docs/current/ecpg-informix-compat.html Best regards, Takeshi Ideriha
On Tue, Jun 7, 2022 at 08:28:55AM +0000, ideriha.takeshi@fujitsu.com wrote: > Hi. > (CCing Michael Meskes) > > One of my customers asked me about what oracle compatibility mode in ecpg means, > and I noticed current documentation does not explain ecpg ORACLE compatible mode (ecpg -C ORACLE) in detail. > I myself learned the feature of "-C ORACLE" from regression test (src/interfaces/ecpg/test/compat_oracle) and source code. > > Is lacking documentation intentional or do commit 3b7ab4380 and 3b9b7516f just forget adding the explanation? > > As for as I know, "ecpg -C ORACLE" is written briefly in ecpg command reference and PostgreSQL 11 release note, > but they are not enougn information for users to understand feature of "ecpg -C ORACLE". > > https://www.postgresql.org/docs/current/app-ecpg.html > > ------------------------------- > -C mode > Set a compatibility mode. mode can be INFORMIX, INFORMIX_SE, or ORACLE. > ------------------------------- > > https://www.postgresql.org/docs/11/release-11.html#id-1.11.6.21.5.9 > ------------------------------- > Add an ecpg mode to enable Oracle Pro*C-style handling of char arrays. > > This mode is enabled with -C. > ------------------------------- > > On the other hand, informix compatible mode is written in detail. > https://www.postgresql.org/docs/current/ecpg-informix-compat.html This is a very good point. I have studied the issue and created the attached patch to document Oracle-compatibility mode. -- Bruce Momjian <bruce@momjian.us> https://momjian.us EDB https://enterprisedb.com Indecision is a decision. Inaction is an action. Mark Batterson
Вложения
On Sat, Jul 09, 2022 at 09:15:52PM -0400, Bruce Momjian wrote: > This is a very good point. I have studied the issue and created the > attached patch to document Oracle-compatibility mode. > ... Looks good to me. Thanks a bunch Bruce. I wonder if we should also mention somewhere that some other Oracle compatibility features are enable in all modes, like a slightly different CONNECT syntax. Michael -- Michael Meskes Michael at Fam-Meskes dot De Michael at Meskes dot (De|Com|Net|Org) Meskes at (Debian|Postgresql) dot Org
On Tue, Jul 12, 2022 at 10:20:08AM +0200, Michael Meskes wrote:
> On Sat, Jul 09, 2022 at 09:15:52PM -0400, Bruce Momjian wrote:
> > This is a very good point. I have studied the issue and created the
> > attached patch to document Oracle-compatibility mode.
> > ...
>
> Looks good to me. Thanks a bunch Bruce.
Great, thanks.
> I wonder if we should also mention somewhere that some other Oracle
> compatibility features are enable in all modes, like a slightly different
> CONNECT syntax.
Good question. We support syntax from other databases, only sometimes
with documentation. I think the rules we use are that we document
compatibility-only behavior when it is useful and obviously if it is
turned in by an option.
In contrast, look at this from backend/parser/gram.y:
/* INOUT is SQL99 standard, IN OUT is for Oracle compatibility */
arg_class: IN_P { $$ = FUNC_PARAM_IN; }
| OUT_P { $$ = FUNC_PARAM_OUT; }
| INOUT { $$ = FUNC_PARAM_INOUT; }
| IN_P OUT_P { $$ = FUNC_PARAM_INOUT; }
| VARIADIC { $$ = FUNC_PARAM_VARIADIC; }
We don't document "IN OUT" anywhere, we just support it silently for
Oracle compatibility, and I am guessing your ecpg connection syntax is
similar. I think this is done so we don't confuse people with syntax
that has not value unless they are coming from another database.
Therefore, I don't think we should document it, but I would be
interested to hear if anyone disagrees.
--
Bruce Momjian <bruce@momjian.us> https://momjian.us
EDB https://enterprisedb.com
Indecision is a decision. Inaction is an action. Mark Batterson
RE: No documentation exists about ecpg ORACLE comptaible mode
От
"ideriha.takeshi@fujitsu.com"
Дата:
Bruce Momjian <bruce@momjian.us> wrote: > This is a very good point. I have studied the issue and created the attached patch to document Oracle-compatibility mode. Hi Bruce, thank you for writing the document. I checked it and I'm very glad! Regards, Takeshi Ideriha
On Thu, Jul 14, 2022 at 02:41:45AM +0000, ideriha.takeshi@fujitsu.com wrote: > Bruce Momjian <bruce@momjian.us> wrote: > > > This is a very good point. I have studied the issue and created the attached patch to document Oracle-compatibilitymode. > > Hi Bruce, thank you for writing the document. > I checked it and I'm very glad! Patch applied to PG 11, where the feature was added, and later. -- Bruce Momjian <bruce@momjian.us> https://momjian.us EDB https://enterprisedb.com Indecision is a decision. Inaction is an action. Mark Batterson