Initial commit

python/sqlalchemy/core.py

@@ -0,0 +1,70 @@
+from sqlalchemy import MetaData
+from sqlalchemy import Table, Column, Integer, String
+from sqlalchemy import create_engine
+from sqlalchemy import ForeignKey
+
+# Model declarations
+metadata_obj = MetaData()
+
+user_table = Table(
+    "user_account",
+    metadata_obj,
+    Column('id', Integer, primary_key=True),
+    Column('name', String(30)),
+    Column('fullname', String)
+)
+
+address_table = Table(
+    "address",
+    metadata_obj,
+    Column('id', Integer, primary_key=True),
+    Column('user_id', ForeignKey('user_account.id'), nullable=False),
+    Column('email_address', String, nullable=False)
+)
+
+# Connection
+engine = create_engine("sqlite+pysqlite:///:memory:", future=True)
+
+# Model migration
+metadata_obj.create_all(engine)
+
+
+
+# INSERT
+from sqlalchemy import insert, select
+
+# values method
+stmt = insert(user_table).values(name='spongebob', fullname="Spongebob Squarepants")
+with engine.begin() as conn:
+    conn.execute(stmt)
+
+
+# autogenerate values
+with engine.connect() as conn:
+    conn.execute(
+        insert(user_table),
+        [
+            {"name": "sandy", "fullname": "Sandy Cheeks"},
+            {"name": "patrick", "fullname": "Patrick Star"}
+        ]
+    )
+    conn.commit()
+
+
+# insert..select
+select_stmt = select(user_table.c.id, user_table.c.name + "@aol.com")
+insert_stmt = insert(address_table).from_select(
+    ["user_id", "email_address"], select_stmt
+)
+with engine.begin() as conn:
+    res = conn.execute(insert_stmt)
+
+
+
+# SELECT
+from sqlalchemy import select
+
+stmt = select(user_table).where(user_table.c.name == 'spongebob')
+with engine.connect() as conn:
+    for row in conn.execute(stmt):
+        print(row)

python/sqlalchemy/orm.py

@@ -0,0 +1,54 @@
+from sqlalchemy import Column, Integer, String
+from sqlalchemy import create_engine
+from sqlalchemy import ForeignKey
+from sqlalchemy.orm import Session
+from sqlalchemy.orm import registry
+from sqlalchemy.orm import relationship
+
+mapper_registry = registry()
+Base = mapper_registry.generate_base()
+
+# from sqlalchemy.orm import declarative_base
+# Base = declarative_base()
+
+
+
+class User(Base):
+    __tablename__ = 'user_account'
+
+    id = Column(Integer, primary_key=True)
+    name = Column(String(30))
+    fullname = Column(String)
+
+    addresses = relationship("Address", back_populates="user")
+
+    def __repr__(self):
+        return f"User(id={self.id!r}, name={self.name!r}, fullname={self.fullname!r})"
+
+
+
+class Address(Base):
+    __tablename__ = 'address'
+
+    id = Column(Integer, primary_key=True)
+    email_address = Column(String, nullable=False)
+    user_id = Column(Integer, ForeignKey('user_account.id'))
+
+    user = relationship("User", back_populates="addresses")
+
+    def __repr__(self):
+        return f"Address(id={self.id!r}, email_address={self.email_address!r})"
+
+
+engine = create_engine("sqlite+pysqlite:///:memory:", future=True)
+Base.metadata.create_all(engine)
+
+
+
+
+# SELECT
+from sqlalchemy import select
+stmt = select(User).where(User.name == 'spongebob')
+with Session(engine) as conn:
+    for row in conn.execute(stmt):
+        print(row)