python + SQLAlchemy: deleting with the Session object

Solution 1:

In SQL Alchemy you are deleting Objects that you get with a query from the database. This you can do in 2 Ways:

Deleting with query (will issue just one DELETE statement):

session.query(User).filter(User.id==7).delete()
session.commit()

Deleting object instance returned by a query (will issue 2 statements: first SELECT, then DELETE):

obj=session.query(User).filter(User.id==7).first()
session.delete(obj)
session.commit()

Delete All Records

#for all records
session.query(Model).delete()
session.commit()

Deleted Single Row

If you want to delete specific records then try filter clause in the query. ex.

#for specific value
session.query(Model).filter(Model.id==123).delete()
session.commit()

Delete Single Record by Object

record_obj = session.query(Model).filter(Model.id==123).first()
session.delete(record_obj)
session.commit()

https://flask-sqlalchemy.palletsprojects.com/en/2.x/queries/#deleting-records