Need Syntax Examples: scope & accessing relational database/class object data

[Build Python Web Apps with Flask Skill Path](https://Build Python Web Apps with Flask Skill Path) was very helpful, but I am struggling with manipulating output of database queries to access data due to syntax.
Sqlalchemy does make life easier to access Python object classes, but for me, raw SQL was easier to manipulate relationships between tables. I can go back to the course to get examples, but these examples are limited in context it becomes cumbersome to find examples.

For example, do I need to two related tables separately to filter out a shared element? (SQL: Where PK_id=FK_id)

For beginners like me, examples of correct syntax are always best.

Is there is a good Codeacademy or other resource available to find syntax examples of Python object/database manipulation?