simphony-osp Data migration of db wrapper upon ontology update

Updating the underlying ontology might make a DB used by a DB wrapper unusable due to a change in the DB schema or another reason depending on the wrapper implementation. Since ontology updates are possible and expected to occur, it would be beneficial to offer a generic solution to this problem.

Aug 27 '20 15:08 yoavnash

Naive solution: have two db-wrappers each with a separate database where one follows the old schema and the other follows the new one. Write an OSP-core script that reads all the data from the old DB, updates it according to the new schema, and then adds it to the new DB.

Aug 27 '20 15:08 yoavnash

But the naive solution doesn't cover the ontology update case, does it?

Aug 28 '20 05:08 urbanmatthias

Even if the two versions of the ontology have two separate namespaces (so they can be installed at the same time)?

Aug 28 '20 07:08 yoavnash

Ontology version 1: Entity A has attribute C. Ontology version 2: Entity A is related to B. B has attribute C.

If you have all data in ontology v1 format, how would you introduce the B instances? The naive solution you propose wouldn't. Or would it?

Aug 31 '20 05:08 urbanmatthias

b = myonto_v2.B(c=old_a.c)
a = myonto_v2.A()
a.add(b)

Oct 07 '20 08:10 yoavnash

Decisions from the meeting last week:

As a first solution, we want to support a way that allows a user to manually update his data.
There should be a tool that supports the ontology updates that have been made.
Two discussed solutions:
1. Special ontology update mode where union of ontologies is installed. The user can then update his cuds objects to the new ontology.
2. Allow to install the new ontology under a new name. Then the user can recreate the data under the new ontology. Problem: After the new ontology has been removed, the user might want to rename the new ontology.

--> We try solution 1 first. --> There should be an example that explains the ontology update procedure.

Nov 02 '20 07:11 urbanmatthias

@yoavnash if I understood correctly, your modular design should help in this regard correct? Do you want to add a couple of sentences?

Mar 17 '21 07:03 urbanmatthias

One idea that we could explore is the use of a standard mapping tool to achieve the following kind of flow:

Such a tool can have the following functionality:

Mar 17 '21 09:03 yoavnash