Hello KK,
In the beginning, it was a little challenging, but as the process went on it became easy. No, it was not a multistage upgrade. It was possible to upgrade straight from 9.5 to 14.
We did not change anything on the schema. For data type, we alter all tables that were created with OIDs to remove the OIDs. We remove all data with abs time ( absolute time). We equally remove all data with sql_identifier. We also created a script to check for unknown data type and another to remove them.
For documentation, we did not use any specific documentation. We just followed postgresql documentation on upgrading. We created our one plan and steps based on our clusters, ensuring we can safely roll back in case of any challenges.
Thank you.
Johnathan T
On Tue, Jul 11, 2023 at 5:17 AM KK CHN <kkchn.in@xxxxxxxxx> wrote:
Hi Johnathan,1. How complex was it upgrading from an old Postgres 9.5 to 14.8 ? Is it multistage upgrading or single shot to 14.8 ?2. What about the old schema ( data types of 9.8 when the database was designed couple of years ago? and the datatypes supported in 14.8 is there any manual work was involved in this migration , please let me know the manual works needed to perform while migration from 9.8 to 14.8)3. Which documentation needs to be followed to perform this upgrade ??Any hints much appreciated..KrishaneOn Mon, Jul 10, 2023 at 11:46 PM Johnathan Tiamoh <johnathantiamoh@xxxxxxxxx> wrote:Hello,I upgraded from postgresql 9.5 to 14.8. After the upgrade users were not able to connect due to password hash.The password encryption was on scram-sha-256. The password hash was on md5. in the pg_hba.conf file the authentication method was md5. I do not know why users could not connect because as per postgresql documentation, that should work.I have previously done a similar upgrade and did not face similar issues.Kind regardsJohnathan Tiamoh