I wrote a module which is to create an empty database file
def create_database():
engine = create_engine("sqlite:///myexample.db", echo=True)
metadata = MetaData(engine)
metadata.create_all()
But in another function, I want to open myexample.db
database, and create tables to it if it doesn't already have that table.
EG of the first, subsequent table I would create would be:
Table(Variable_TableName, metadata,
Column('Id', Integer, primary_key=True, nullable=False),
Column('Date', Date),
Column('Volume', Float))
(Since it is initially an empty database, it will have no tables in it, but subsequently, I can add more tables to it. Thats what i'm trying to say.)
Any suggestions?
I've managed to figure out what I intended to do. I used engine.dialect.has_table(engine, Variable_tableName)
to check if the database has the table inside. IF it doesn't, then it will proceed to create a table in the database.
Sample code:
engine = create_engine("sqlite:///myexample.db") # Access the DB Engine
if not engine.dialect.has_table(engine, Variable_tableName): # If table don't exist, Create.
metadata = MetaData(engine)
# Create a table with the appropriate Columns
Table(Variable_tableName, metadata,
Column('Id', Integer, primary_key=True, nullable=False),
Column('Date', Date), Column('Country', String),
Column('Brand', String), Column('Price', Float),
# Implement the creation
metadata.create_all()
This seems to be giving me what i'm looking for.