Is the custom function in the database template duplicated in the new database?

Question

PostgreSQL

Create a new function calculate(0 in database schema A, then create database B, is the function duplicated or is it only available within the 1st database?

Answer 1

It depends on how exactly you create base B. Namely, what exactly will be specified in the template parameter.
If template points to the database where you created the storage, then this database will be completely cloned, including storages.
If the template points to where this storage is not, then it will not be in the created database.
The default base is template1.