[web2py] Query results from 2 children tables from same parent ordered by date

[Mamisoa Andriantafika]

Hi,

I have this db model:

db.define_table('patients',
    Field('name', 'string', length=32),
    Field('firstname', 'string', length=32),
    Field('dob', 'date'),
    format='%(name)s')

db.define_table('dataset1',
    Field('date', 'date', length=32),
    Field('param1', 'string', length=50),
    Field('param2', 'string', length=50),    
    Field('patient_id', db.patients, writable=False, readable=False))

db.define_table('dataset2',
    Field('date', 'date', notnull=True),
    Field('test1', 'text'),
    Field('patient_id', db.patients, writable=False, readable=True))

I'd like to show in one view, for 1 patient_id, all the corresponding 
dataset1 and dataset2 ordered by date.

What query should I use? Do I have to use an intermediate table 'history' 
to record each activity in dataset1/2 to get a result?

Thanks for help.

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