Answer 1

Sqlite is a database storage engine, which can be better compared with things such as MySQL, PostgreSQL, Oracle, MSSQL, etc. It is used to store and retrieve structured data from files. SQLAlchemy is a Python library that provides an object relational mapper

Answer 2

My pleasure

Answer 3

If you learn SQL language you will easily deal with anything MySQL, sqlite. Because the different is the syntax only

Answer 4

Different relational databases plus an ORM.