Using an existing Postgres 16 instance instead of ossapps/postgres image?

[GiamBoscaro]

I have a Postgres 16 container running that hosts already a few DBs from my services. I would like to have also the SplitPro database in there, but I have seen that in the docker installation here in the repo it is being used a custom image ossapps/postgres.

• If I host the database in my own Postgres instance, will I break something?
• What exactly is added into the ossapps/postgres image? Only the the pg_cron plugin is being installed. I suppose I could install that also in my own Postgres instance.

[krokosik]

I suppose you can do that. Our image is only for adding pg_cron indeed, which won't be needed until 1.6 is released.

[GiamBoscaro]

I suppose you can do that. Our image is only for adding pg_cron indeed, which won't be needed until 1.6 is released.

I will try to add pg_cron to my Postgres instance so I am ready for 1.6.

[laur89]

@krokosik do you have pointers on setting up the pg_cron extension? After installing it, there are still some permission issues:

2026-03-30 16:20:42.246 CEST [41] ERROR:  permission denied to create extension "pg_cron"
2026-03-30 16:20:42.246 CEST [41] HINT:  Must be superuser to create this extension.
2026-03-30 16:20:42.246 CEST [41] CONTEXT:  SQL statement "CREATE EXTENSION IF NOT EXISTS pg_cron"
        PL/pgSQL function inline_code_block line 4 at SQL statement
2026-03-30 16:20:42.246 CEST [41] STATEMENT:  DO $$
        BEGIN
        IF current_database() NOT LIKE 'prisma_migrate_shadow_db%' THEN
          CREATE EXTENSION IF NOT EXISTS pg_cron;
        ELSE
            CREATE SCHEMA IF NOT EXISTS cron;
            CREATE TABLE IF NOT EXISTS cron.job (
                jobid BIGINT PRIMARY KEY,
                schedule TEXT,
                command TEXT,
                nodename TEXT,
                nodeport INTEGER,
                database TEXT,
                username TEXT,
                active BOOLEAN,
                jobname TEXT
            );
        END IF;
        END $$;

Should cron.database_name be set to our splitpro db or postgres? Did try both with no luck.

And splitpro logs have:

Raw query failed. Code: `42501`. Message: `ERROR: permission denied to create extension "pg_cron"
HINT: Must be superuser to create this extension.`
prisma:error Raw query failed. Code: `42501`. Message: `ERROR: permission denied to create extension "pg_cron"
HINT: Must be superuser to create this extension.`

[laur89]

This locks split pro into using db superuser, which nobody should do if the db is shared.

[krokosik]

Well if someone wants to use the DB as a shared one, then it is their responsibility. There is a limit to the length I will go to cater to every use case, I'm sorry.

If someone is technical enough to run a shared PG container, they are probably capable of installing an extension by themselves, for example by granting the permissions for the migration and taking them away afterwards.

[laur89]

for example by granting the permissions for the migration and taking them away afterwards.

I'm not all that familiar with postgres, but how would that look like?

SELECT extname, extversion FROM pg_extension;
 extname | extversion 
---------+------------
 plpgsql | 1.0
 pg_cron | 1.6

shows cron extension is installed. But the migration's create extension statement still appears to be executing.

[krokosik]

I'm at a loss to try to understand what you are trying to do. You have an existing postgres container, in which you want to add a splitpro database, but upon running splitpro (and the prisma migrations), the migration fails?

[laur89]

Think I'm just lacking some core understanding of how pg_cron extension is supposed to be set up and used by the apps. I'll just stand up second db for split-pro.

Thanks for your patience.