what is the correct way to rename partitioned table?

[virajbz]

Postgres 13.10
partman extension version: 4.5.1

Scenario: Partitioning existing table with exact same schema. The original table only has inserts no updates or deletes
Steps:

1. create a new table with partitions 'table_partitioned'. use partman.create_parent to precreate partitions. setup after insert trigger to replicate live inserts from 'table' to 'table_partitioned'.
2. backfill old records from 'table' to 'table_partitioned'. At this point both tables are in sync.
3. Cutover: drop the trigger to sync tables. rename 'table' to 'table_old and 'table_partitioned' to 'table'.

After above steps partman.show_partitions throws exception [P0001] ERROR: Given parent table not managed by pg_partman:
Since part_config still has 'public.table_partitioned' as parent.
How to we handle this?
Simply renaming all partitions and parent table in part_config and template table name is enough?
One approach
Creating a template table manually in partman schema with name 'table'. That takes care of template table name but child tables still get created using parent table name.

[keithf4]

Yes, just update the parent_table value in the part_config table. Also review the values of the other columns in the part_config table as well to see what else needs to be updated. For example, if you're renaming the template table, then you'll have to update that value in part_config as well.
The name of the child tables is based on the parent table name, not the template table.

Even if you're not able t update to version 5 of pg_partman yet, I would highly recommend updating to at least the latest 4 version. There have been quite a few bug fixes since 4.5.1

https://github.com/pgpartman/pg_partman/blob/master/CHANGELOG-pre-5.0.0.txt

[keithf4]

Functions in PG are always atomic and executed as one single transaction. It's either all or nothing from when it's called to when it finishes and if there are any errors, it will be entirely rolled back.

If you want individual statements to be committed, look into making it a PROCEDURE instead.

[keithf4]

If you want some other ideas for doing object renames, see some of the migration docs. For example, I just have it generate the ALTER statements and then execute those separately

https://github.com/pgpartman/pg_partman/blob/master/doc/migrate_to_partman.md#step-3a

[virajbz]

I will make few logging changes and stick to the function to do all the job. We strictly take DDL changes via flyway, that too single source of truth for all zones. Thanks for your help @keithf4 :)