_sql1 = db(db.logs.date.year()==2010)._select(db.logs.date, db.logs.item, groupby=db.logs.item) rows = db(db.logs.item.belongs(_sql1) & (db.stock.item == db.logs.item)).select(db.logs.date,db.logs.item.count(), groupby=db.logs.date)
notice _select for the first query