Re: v11.5- v15.3 upgrade (linux)

On 3/8/24 09:09, Adrian Klaver wrote:
> On 3/8/24 08:57, David Gauthier wrote:
>> Thanks for the reply.
>>
>> When you say "dump/restore" do you mean pg_dump then running the 
>> resulting SQL into the destination DB?
>> I like the replication option myself best (min downtime), especially 
>> as we use a DB alias for connections.  But I don't think I'll be able 
>> to sell that to the IT group.
> 
> You said the dump/restore has been tested.
> 
> How long did that take?
> 
>>
>> Regarding the safety of running a "drop extension plperlu cascade" on 
>> the v11.5, would you consider that to be safe GIVEN that there are no 
>> plperlu procs that it will affect?  I need to be able to tell IT that 
>> I'm not the only one who thinks that it's safe.
> 
> BEGIN;
> 
> DROP LANGUAGE plperlu;

Arrgh. That should be

DROP EXTENSION plperlu;

> 
> ROLLBACK;
> 
> See if the above complains about anything depending on it.
> 
> If not:
> 
> DROP EXTENSION plperlu;
> 
>>
>>
>>
>> On Fri, Mar 8, 2024 at 11:28 AM Yogesh Sharma 
>> <yogesh.sharma@catprosystems.com 
>> <mailto:yogesh.sharma@catprosystems.com>> wrote:
>>
>>     Greetings,
>>
>>     On 3/6/24 19:19, David Gauthier wrote:
>>      > Hi:
>>      > I'm a PG user in a big corp with an IT dept that administers a PG
>>      > server/instance that I use.  It's an old install, v11.5, and we 
>> need
>>      > to upgrade to v15.3.  They want to bring the upgraded DB up on 
>> a new
>>      > linux vm which has OS upgrades of its own.  So it's a move AND an
>>      > upgrade. There are 2 concerns....
>>      >
>>      > First has to do with a jump from 11.5 - 15.3 ?  Is it safe to do
>>     this
>>      > given so many major intermediate versions being skipped ?
>>
>>     Generally speaking, it is safe from database point of view but you 
>> have
>>     to verify that application is working as expected with PostgreSQL 15,
>>     driver update, any query performance issues, any deprecate 
>> features in
>>     use, collation differences, and performance verification, etc.
>>
>>     PostgreSQL supports dump/restore (slow and longer downtime), binary
>>     upgrade using pg_upgrade (faster and low downtime), and logical
>>     replication (complex and least downtime). Since OS upgrade is also 
>> part
>>     of the equation, dump/restore or logical  are better candidates. 
>> Due to
>>     OS collation difference I would avoid binary upgrade path.
>>
>>
>>     --     Kind Regards,
>>     Yogesh Sharma
>>     PostgreSQL, Linux, and Networking Expert
>>     Open Source Enthusiast and Advocate
>>     PostgreSQL Contributors Team @ RDS Open Source Databases
>>     Amazon Web Services: https://aws.amazon.com <https://aws.amazon.com>
>>
> 

-- 
Adrian Klaver
adrian.klaver@aklaver.com