hmmm_scratches_head.py

# Trying to filter on a hybrid_property

# This should return all but one of them (12 out of 13)
In [590]: active = db.session.query(db.Trade).filter(db.Trade.active == True).all()
# Nope
In [591]: active
Out[591]: []

# Try this?
In [592]: active = db.session.query(db.Trade).filter(db.Trade.active).all()
# Nope
In [593]: active
Out[593]: []

# This should select one of them (1 out of 13)
In [594]: active = db.session.query(db.Trade).filter(db.Trade.active == False).all()
# Return all of them (13/13) but can see active property is indeed properly set and working with each
In [595]: active
Out[595]:
[<Trade (symbol=BBDO, buy_date=2014-01-02 12:12:35.804996, perc=-5, active=False)>,
 <Trade (symbol=DEG, buy_date=2014-01-02 12:12:35.804996, perc=-5, active=True)>,
 <Trade (symbol=YZC, buy_date=2014-01-02 12:12:35.804996, perc=-5, active=True)>,
 <Trade (symbol=HLF, buy_date=2014-01-03 11:33:02.190683, perc=-3, active=True)>,
 <Trade (symbol=NUS, buy_date=2014-01-03 11:33:02.190683, perc=-3, active=True)>,
 <Trade (symbol=S, buy_date=2014-01-03 11:33:02.190683, perc=-3, active=True)>,
 <Trade (symbol=TMUS, buy_date=2014-01-03 11:33:02.190683, perc=-3, active=True)>,
 <Trade (symbol=CTRP, buy_date=2014-01-03 11:33:02.190683, perc=-5, active=True)>,
 <Trade (symbol=ASR, buy_date=2014-01-03 16:53:44.450940, perc=-3, active=True)>,
 <Trade (symbol=GM, buy_date=2014-01-03 16:53:44.450940, perc=-3, active=True)>,
 <Trade (symbol=IGLD, buy_date=2014-01-03 16:53:44.450940, perc=-3, active=True)>,
 <Trade (symbol=MU, buy_date=2014-01-03 16:53:44.450940, perc=-3, active=True)>,
 <Trade (symbol=VIP, buy_date=2014-01-03 16:53:44.450940, perc=-3, active=True)>]

# Okay, this is now odd - 
In [610]: active = db.session.query(db.Trade).filter(db.Trade.active==True)

In [611]: print active
SELECT trades.id AS trades_id, trades.stock_id AS trades_stock_id, trades.quantity AS trades_quantity, trades.buy_price AS trades_buy_price, trades.buy_datetime AS trades_buy_datetime, trades.sell_price AS trades_sell_price, trades.sell_datetime AS trades_sell_datetime, trades.buy_percent_drop AS trades_buy_percent_drop, trades.sell_percent_change AS trades_sell_percent_change
FROM trades
WHERE false

# However, this works fine since we exclude that first one where active is False - 
In [687]: for trade in db.session.query(db.Trade).all():
    if trade.active == True:
        print trade
   .....:
<Trade (symbol=DEG, buy_date=2014-01-02 12:12:35.804996, perc=-5, active=True)>
<Trade (symbol=YZC, buy_date=2014-01-02 12:12:35.804996, perc=-5, active=True)>
<Trade (symbol=HLF, buy_date=2014-01-03 11:33:02.190683, perc=-3, active=True)>
<Trade (symbol=NUS, buy_date=2014-01-03 11:33:02.190683, perc=-3, active=True)>
<Trade (symbol=S, buy_date=2014-01-03 11:33:02.190683, perc=-3, active=True)>
<Trade (symbol=TMUS, buy_date=2014-01-03 11:33:02.190683, perc=-3, active=True)>
<Trade (symbol=CTRP, buy_date=2014-01-03 11:33:02.190683, perc=-5, active=True)>
<Trade (symbol=ASR, buy_date=2014-01-03 16:53:44.450940, perc=-3, active=True)>
<Trade (symbol=GM, buy_date=2014-01-03 16:53:44.450940, perc=-3, active=True)>
<Trade (symbol=IGLD, buy_date=2014-01-03 16:53:44.450940, perc=-3, active=True)>
<Trade (symbol=MU, buy_date=2014-01-03 16:53:44.450940, perc=-3, active=True)>
<Trade (symbol=VIP, buy_date=2014-01-03 16:53:44.450940, perc=-3, active=True)>

# FIXED... has to be something like:        
return self.sell_datetime == None
# rather than since this won't operate at the db level in sqlalchemy
if not self.sell_datetime:
 return True
return False