Multi-tenancy met SQLAlchemy

Na nadenken over het antwoord van jd kon ik hetzelfde resultaat bereiken voor postgresql 9.2, sqlalchemy 0.8 en flask 0.9 framework:

from sqlalchemy import event
from sqlalchemy.pool import Pool
@event.listens_for(Pool, 'checkout')
def on_pool_checkout(dbapi_conn, connection_rec, connection_proxy):
    tenant_id = session.get('tenant_id')
    cursor = dbapi_conn.cursor()
    if tenant_id is None:
        cursor.execute("SET search_path TO public, shared;")
    else:
        cursor.execute("SET search_path TO t" + str(tenant_id) + ", shared;")
    dbapi_conn.commit()
    cursor.close()