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In each facility you have a database server up and running with Postgres installed.

Concept

Each facility has a database server. For each site the facility library is the main library. The libraries from other facilities are replications. These replications are read-only. This means that every site is independent but still benefits from the work and libraries another facility is doing.

In Postgres terms:
A logical replication is the preferred way to go, since each facility can have their own database setup and also different version of Postgres without running into any issues.
That’s not possible Physical replication, since the Postgres version as well as the folder/file structure needs to be identical.

With logical we have one Publisher and as many Subscribers as we like. The Subscribers will be the Postgres databases in the other facilities.

Create primary database server

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