#Python postgresql vs mysql how to#
#Python postgresql vs mysql code#
#Python postgresql vs mysql password#

Now create all the model (class) attributes.Įach of these attributes represents a column in its corresponding database table. The _tablename_ attribute tells SQLAlchemy the name of the table to use in the database for each of these models. database import Base class User ( Base ): _tablename_ = 'users' id = Column ( Integer, primary_key = True, index = True ) email = Column ( String, unique = True, index = True ) hashed_password = Column ( String ) is_active = Column ( Boolean, default = True ) items = relationship ( 'Item', back_populates = 'owner' ) class Item ( Base ): _tablename_ = 'items' id = Column ( Integer, primary_key = True, index = True ) title = Column ( String, index = True ) description = Column ( String, index = True ) owner_id = Column ( Integer, ForeignKey ( 'users.id' )) owner = relationship ( 'User', back_populates = 'items' ) To create the SessionLocal class, use the function sessionmaker:įrom sqlalchemy import Boolean, Column, ForeignKey, Integer, String from sqlalchemy.orm import relationship from. We will use Session (the one imported from SQLAlchemy) later. We name it SessionLocal to distinguish it from the Session we are importing from SQLAlchemy. The class itself is not a database session yet.īut once we create an instance of the SessionLocal class, this instance will be the actual database session. Create a SessionLocal class ¶Įach instance of the SessionLocal class will be a database session. This is to prevent accidentally sharing the same connection for different things (for different requests).īut in FastAPI, using normal functions ( def) more than one thread could interact with the database for the same request, so we need to make SQLite know that it should allow that with connect_args=.Īlso, we will make sure each request gets its own database connection session in a dependency, so there's no need for that default mechanism. In a similar way you could use any other ORM.īy default SQLite will only allow one thread to communicate with it, assuming that each thread would handle an independent request.

#Python postgresql vs mysql how to#

Here we will see how to work with SQLAlchemy ORM. So, orion_ could be the name (from the name column in the owners table) of this pet's owner.Īnd the ORM will do all the work to get the information from the corresponding table owners when you try to access it from your pet object.Ĭommon ORMs are for example: Django-ORM (part of the Django framework), SQLAlchemy ORM (part of SQLAlchemy, independent of framework) and Peewee (independent of framework), among others. This way, you could also have an attribute orion_cat.owner and the owner would contain the data for this pet's owner, taken from the table owners. These ORMs also have tools to make the connections or relations between tables or entities.

And the value of that attribute could be, e.g. With an ORM, you normally create a class that represents a table in a SQL database, each attribute of the class represents a column, with a name and a type.įor example a class Pet could represent a SQL table pets.Īnd each instance object of that class represents a row in the database.įor example an object orion_cat (an instance of Pet) could have an attribute orion_cat.type, for the column type.

#Python postgresql vs mysql code#

ORMs ¶įastAPI works with any database and any style of library to talk to the database.Ī common pattern is to use an 'ORM': an 'object-relational mapping' library.Īn ORM has tools to convert (' map') between objects in code and database tables (' relations'). The FastAPI specific code is as small as always. Notice that most of the code is the standard SQLAlchemy code you would use with any framework.

#Python postgresql vs mysql password#

OAuth2 with Password (and hashing), Bearer with JWT tokensĬreate SQLAlchemy models from the Base classĬreate Pydantic models / schemas for reading / returningĬustom Response - HTML, Stream, File, othersĪlternatives, Inspiration and Comparisons Dependencies in path operation decorators