Re: Backward compatibility

Hi, David,

On Thu, Jul 20, 2017 at 10:23 PM, David G. Johnston
<david(dot)g(dot)johnston(at)gmail(dot)com> wrote:
> On Thu, Jul 20, 2017 at 7:13 PM, Igor Korot <ikorot01(at)gmail(dot)com> wrote:
>>
>> Hi, ALL,
>> According to the documentation PostgreSQL 9.6 (latest) supports
>>
>> CREATE INDEX IF NOT EXIST
>>
>> However, the version 9.4 and below supports only
>>
>> CREATE INDEX.
>>
>> Is there a query or a libpg function which can return the version of
>> the server I'm running?
>
>
> SHOW server_version_num; -- this is better than "version()" since you don't
> have to parse text
>
> https://www.postgresql.org/docs/9.6/static/runtime-config-preset.html#GUC-SERVER-VERSION-NUM

draft=# SHOW server_version_num;
server_version_num
--------------------
90124
(1 row)

Is there a way to get a version_major, version_minr and version_extra?

Thank you.

>
> see the below for other ways to query the setting.
>
> https://www.postgresql.org/docs/9.6/static/config-setting.html#CONFIG-SETTING-SQL-COMMAND-INTERACTION
>
>>
>> And in the latter case - is there a way to check if the index exist?
>>
>> I guess I will have to query "information_schema" again...
>>
>
> Yep, not much demand for multiple ways to do the same thing in this area...
>
> David J.
>