How to create only one table with SQLAlchemy?

Above, the declarative_base() callable returns a new base class from which all mapped classes should inherit. When the class definition is completed, a new Table and mapper() will have been generated.

The resulting table and mapper are accessible via __table__ and __mapper__ attributes

(From here)

Therefore:

def build_daily_history_table(ticket):
    classname = ticket + "_HistoricDay"
    ticket = type(classname, (Base, HistoricDay), {'__tablename__' : ticket+"_daily_history"})
    ticket.__repr__ =  build_daily_history_table_repr
    return ticket

build_daily_history_table("test").__table__.create(bind = engine)

Output:

2013-10-04 22:36:53,263 INFO sqlalchemy.engine.base.Engine 
CREATE TABLE test_daily_history (
    id INTEGER NOT NULL, 
    date DATE, 
    open FLOAT, 
    high FLOAT, 
    low FLOAT, 
    close FLOAT, 
    volume BIGINT, 
    "adjClose" FLOAT, 
    PRIMARY KEY (id)
)


2013-10-04 22:36:53,263 INFO sqlalchemy.engine.base.Engine ()
2013-10-04 22:36:53,263 INFO sqlalchemy.engine.base.Engine COMMIT

Credit goes to javex's comment/correction or I might have suggested something akin to:

Base.metadata.tables["ticket_daily_history"].create(bind = engine)

Advise:

The approach used in build_daily_history_table could be one of the least elegant ways of doing things, primarily for the reason that it is polluting/cluttering the namespace.

To create specific tables, giving tables parameter to create_all() method is enough.

Base.metadata.create_all(engine, tables=table_objects)

table_objects equals to:

table_objects = [HistoricDay.__table__]

table_objects = [Base.metadata.tables["historicday"]]

I showed one table here. You can increase the number of the tables as you wish.

Reference: http://docs.sqlalchemy.org/en/latest/core/metadata.html#sqlalchemy.schema.MetaData.create_all

Create all not exists tables with one line. It will check whether the table exists first by default.

Base.metadata.create_all(db_engine, Base.metadata.tables.values(),checkfirst=True)

Create one target table with table_name.

Base.metadata.create_all(db_engine, Base.metadata.tables[table_name],checkfirst=True)

It works perfectly with declarative_base.

from sqlalchemy.ext.declarative import declarative_base

Base = declarative_base()
TABLE_PREFIX = "decision_"


class Stock(Base):
    __tablename__ = '{}stocks'.format(TABLE_PREFIX)

    id = Column(Integer, primary_key=True)
    name = Column(String)

class StagePerformance(Base):
    __tablename__ = '{}stage_performance'.format(TABLE_PREFIX)

    id = Column(Integer, primary_key=True)
    date = Column(DateTime)
    stock = relationship("Stock", back_populates="stage_performances")
    period = Column(Integer )
    open = Column(Float)
    high = Column(Float)
    low = Column(Float)
    close = Column(Float)
    change_ratio = Column(Float)
    turnover = Column(Float)
    volume = Column(Float)

How to create only one table with SQLAlchemy?

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