did you already create the web2py models for your current database? i mean using the extract script.
e.g.
web2py\scripts\extract_mysql_models.py
without repeating model definitions
pardon me, don't know what do you mean about this, if you mean the repeating model definitions is migrate, i think you can achieve it after you extract the database into models (above steps is done) and set in the dal :
migrate = False, fake_migrate_all = False
nor loading them all.
for this, i think the answer is same like the others suggestion, is to use the modelless (modules) or response.models_to_run(), your choice.
if you follow the above steps (extract, and set the migrate value), i think you only can use response.models_to_run(), because in modelless (modules) you must redefine the tables again in modules.
best regards,
stifan