Upgrading an installation with pg_upgrade v15

While minor upgrades between versions are fairly simple and require only installing new executables, past major version upgrades were both expensive and time consuming. pg_upgrade eases migration between any version of EDB Postgres Advanced Server (version 9.0 or later) and any later release of EDB Postgres Advanced Server that's supported on the same platform.

Without pg_upgrade, to migrate from an earlier version of EDB Postgres Advanced Server to the newest version:

1. Export all of your data using pg_dump.
2. Install the new release.
3. Run initdb to create a new cluster.
4. Import your old data.

The pg_upgrade utility performs an in-place transfer of existing data between EDB Postgres Advanced Server and any later version.

Several factors determine if an in-place upgrade is practical:

• The on-disk representation of user-defined tables must not change between the original version and the upgraded version.
• The on-disk representation of data types must not change between the original version and the upgraded version.
• To upgrade between major versions of EDB Postgres Advanced Server with pg_upgrade, both versions must share a common binary representation for each data type. Therefore, you can't use pg_upgrade to migrate from a 32-bit to a 64-bit Linux platform.

Before performing a version upgrade, pg_upgrade verifies that the old cluster and the new cluster are compatible.

If the upgrade involves a change in the on-disk representation of database objects or data, or if it involves a change in the binary representation of data types, pg_upgrade can't perform the upgrade. To upgrade, you have to pg_dump the old data and then import that data to the new cluster.

The pg_upgrade executable is distributed with EDB Postgres Advanced Server and is installed as part of the Database Server component. You don't need to further install or configure it.