[rbev]

Separate primary and audit SQL schemas

• Keep primary and audit tables in separate default schemas rather than supporting shared-schema installations.
• To ensure that no data loss occurs if a misconfiguration points both audit and error at the same schema it is now checked before making changes.

Why

The schema default was to share the same schema, however there was no testing that ensures this is actually supported.

For SQL Server and PostgreSQL:

• Default audit instances to sc_audit. Leave the error instance schema unset so it uses the connection’s default.
• Preserve explicitly configured Database/Schema values and expose the setting in the error persister manifests.
• Allow setup to create missing schemas when the connection has permission. Connections without schema-creation permission can use a
  pre-created schema.
• Add pre-migration checks intended to prevent error and audit instances from sharing a schema.
• Name the error migrations history table __ErrorMigrationsHistory. Audit continues to use __AuditMigrationsHistory.
• Document schema selection, creation permissions, and existing-data considerations in docs/sql-persister-schemas.md.

Custom schema names remain supported. Operators must create the schema and grant the configured user rights before running setup if the account does not have access to schema creation.

[warwickschroeder]

Two things im not sure about:

1. the default schema naming
2. Throwing if error and audit are on the same schema without a very good reason.

[warwickschroeder]

I thought we were letting SCMU to at least try create the database and schema?

[rbev]

So it seems that SC will create the schema if it can, I'll update the docs to match what is actually true

[warwickschroeder]

It still says it does not create the schema?

[warwickschroeder]

Will also need to update the docs PR

[johnsimons]

Shouldn't this be up to the user to decide?
What exactly is the problem here? As far as I know, there are no sharing of tables.

[rbev]

Shouldn't this be up to the user to decide? What exactly is the problem here? As far as I know, there are no sharing of tables.

This has now been updated to

• use default schema from connection for the error instance
• default the audit to it's own schema and create it if necessary