I have no CLI access on a server, but I want to run automatic deploy releases and backup/restore data contained by multiple pgsql databases. Is there a way to do this with PDO effortless?
Effortless(ly)
No.
You'd basically have to re-implement pg_dump. This would not be fun.
You can COPY out the tables using pg_copy_from. Unsure if there's a PDO equivalent. This will let you dump the data relatively easily, combined with a query against information_schema to get a table list.
Dumping the table definitions, users, constraints, indexes, etc, however ... good luck.