Sqlalchemy if table does not exist

Question

I wrote a module which is to create an empty database file

def create_database():
    engine = create_engine(\"sqlite:///myexample.db\", echo=True)
    metadata          


        

Answer 1

For those who define the table first in some models.table file, among other tables. This is a code snippet for finding the class that represents the table we want to create ( so later we can use the same code to just query it )

But together with the if written above, I still run the code with checkfirst=True

ORMTable.__table__.create(bind=engine, checkfirst=True)

models.table

class TableA(Base):
class TableB(Base):
class NewTableC(Base):

   id = Column('id', Text)
   name = Column('name', Text)

form

Then in the form action file:

engine = create_engine("sqlite:///myexample.db")
if not engine.dialect.has_table(engine, table_name):
   # Added to models.tables the new table I needed ( format Table as written above )
   table_models = importlib.import_module('models.tables')

   # Grab the class that represents the new table
   # table_name = 'NewTableC'
   ORMTable = getattr(table_models, table_name)            

   # checkfirst=True to make sure it doesn't exists
   ORMTable.__table__.create(bind=engine, checkfirst=True)