each $part does not contain ".", so quoteSingleIdentifier may be called directly thus avoiding recursive strpos checks.

Updating a schema should introduce also schema creation statements in the generated SQL

While technically it could work, the schema introspection of Sqlite
platform has severe flaws preventing us to provide reliable support
of partial (and non-partial) indexes for the moment.

This coherent with what is done for Table. All platform specific things
are grouped into an options array. Eventually flags should be migrated
into options as well.