How to force my db_schema.xml to run after a third-party InstallData.php?

Question

I'm working with a legacy module where they used the old InstallData.php script to build their tables, and now I need to make some changes to them.

If I wrote those changes in a db_schema.xml, it gets executed before the original install data even with my module declared to load after theirs on the module.xml, causing a mess in the final result.

Am I missing something?

Answer 1

You are right. You cannot update DB schema with db_schema.xml when the table is not defined in 3rd party module db_schema.xml and creates with InstallData. As you correct said this is related to priority of run upgrade logic.

Single way in your case is add sequence from 3rd party module in your etc/module.xml and make changes with Setup/InstallData in your module.

Answer 2

My suggestion would be that; running the two way in the same time is tricky.

Why not doing your modification to a custom UpgradeData ? Or even using a patch data interface.

To me db_schema is supposed to be the original content which is why it's normal he is executed first, not the final content. Patch and update will modify that content, not the opposite.

To resume :

InstallData (or more likely InstallSchema) or db_schema to create a database structure (but not both)

Then

UpdateData or PatchInterface to update these data.