SQLAlchemy Core OPRET MIDLERTIDIG TABEL SOM

Dette er, hvad jeg kom frem til. Fortæl mig venligst, hvis dette er den forkerte måde at gøre det på.

from sqlalchemy.sql import Select
from sqlalchemy.ext.compiler import compiles


class CreateTableAs(Select):
    """Create a CREATE TABLE AS SELECT ... statement."""

    def __init__(self, columns, new_table_name, is_temporary=False,
            on_commit_delete_rows=False, on_commit_drop=False, *arg, **kw):
        """By default the table sticks around after the transaction. You can
        change this behavior using the `on_commit_delete_rows` or
        `on_commit_drop` arguments.

        :param on_commit_delete_rows: All rows in the temporary table will be
        deleted at the end of each transaction block.
        :param on_commit_drop: The temporary table will be dropped at the end
        of the transaction block.
        """
        super(CreateTableAs, self).__init__(columns, *arg, **kw)

        self.is_temporary = is_temporary
        self.new_table_name = new_table_name
        self.on_commit_delete_rows = on_commit_delete_rows
        self.on_commit_drop = on_commit_drop


@compiles(CreateTableAs)
def s_create_table_as(element, compiler, **kw):
    """Compile the statement."""
    text = compiler.visit_select(element)
    spec = ['CREATE', 'TABLE', element.new_table_name, 'AS SELECT']

    if element.is_temporary:
        spec.insert(1, 'TEMPORARY')

    on_commit = None

    if element.on_commit_delete_rows:
        on_commit = 'ON COMMIT DELETE ROWS'
    elif element.on_commit_drop:
        on_commit = 'ON COMMIT DROP'

    if on_commit:
        spec.insert(len(spec)-1, on_commit)

    text = text.replace('SELECT', ' '.join(spec))
    return text