Thank you for your help - now it works perfect!
2013/2/26 Massimo Di Pierro <[email protected]> > >>> db = DAL() > >>> db.define_table('test',Field('t1'),Field('t2')) > <Table test (id,t1,t2)> > >>> db.test.c12 = Field.Virtual (lambda r: r.test.t1+r.test.t2) > >>> db.test.insert(t1='x',t2='y') > 1L > >>> db.test(1).c12 > 'xy' > > Notice: > > db.test.c12 = Field.Virtual (lambda r: r.test.t1+r.test.t2) > > not > > db.test.c12 = Field.Virtual (lambda r: r.t1+r.t2) > > Moreover this is not valid: > > db(db.test.id>0).**select(db.test.c12) > > you cannot select a virtual field from database. You can select the fields > required to compute the virtual fields: > > db(db.test.id>0).**select(db.test.t1, db.test.t2) > > and you get virtual field automatically: > > for row in db(db.test.id>0).select(db.test.t1, db.test.t2): print row.c12 > > > > On Tuesday, 26 February 2013 15:44:43 UTC-6, mweissen wrote: > >> My try: >> >> db.define_table('test', >> Field('t1'), >> Field('t2'), >> ) >> >> db.test.c12 = Field.Virtual (lambda r: r.t1+r.t2) >> >> def t(): >> return dict(f=db(db.test.id>0).**select( >> db.test.c12, >> ), >> c=db.test(1).c12, >> ) >> >> New version, new message: >> Ticket ID >> >> 127.0.0.1.2013-02-26.22-38-37.**30eb0659-ae50-4985-b105-**f7303ce6b911 >> <class 'sqlite3.OperationalError'> near "<": syntax error Version web2py™ (2, >> 4, 1, 'alpha.2', datetime.datetime(2013, 2, 26, 11, 40, 15)) Python Python >> 2.7.3: D:\Python27\python.exe (prefix: D:\Python27) >> >> >> 2013/2/26 Massimo Di Pierro <[email protected]> >> >>> I get: >>> >>> $ python web2py.py -S welcome >>> Version 2.4.1-alpha.2+timestamp.2013.**02.26.11.40.15 >>> Database drivers available: SQLite(sqlite3), MySQL(pymysql), >>> PostgreSQL(pg8000), IMAP(imaplib) >>> WARNING:web2py:import IPython error; use default python shell >>> Python 2.7.1 (r271:86832, Jul 31 2011, 19:30:53) >>> [GCC 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.15.00)] on >>> darwin >>> Type "help", "copyright", "credits" or "license" for more information. >>> (InteractiveConsole) >>> >>> db.define_table('test', >>> ... Field('t1'), >>> ... Field('t2'), >>> ... ) >>> <Table test (id,t1,t2)> >>> >>> db.test.c12 = Field.Virtual (lambda r: r.t1+r.t2) >>> >>> >>> >>> On Tuesday, 26 February 2013 14:43:15 UTC-6, mweissen wrote: >>> >>>> Sorry, no - same message. >>>> I have taken the last version from trunk one hour ago. >>>> >>>> Ticket ID >>>> >>>> 127.0.0.1.2013-02-26.21-39-35.****e1477239-8991-4217-810f-**9e320d** >>>> af692c >>>> <type 'exceptions.AttributeError'> 'FieldVirtual' object has no >>>> attribute 'type' Version web2py™ (2, 4, 1, 'alpha.2', >>>> datetime.datetime(2013, 2, 25, 23, 19, 14)) Python Python 2.7.3: >>>> D:\Python27\python.exe (prefix: D:\Python27) Traceback >>>> >>>> >>>> 1. >>>> 2. >>>> 3. >>>> 4. >>>> 5. >>>> 6. >>>> 7. >>>> 8. >>>> 9. >>>> 10. >>>> 11. >>>> 12. >>>> 13. >>>> 14. >>>> 15. >>>> 16. >>>> 17. >>>> 18. >>>> 19. >>>> 20. >>>> >>>> >>>> Traceback (most recent call last): >>>> File "D:\web2py\gluon\restricted.**py**", line 212, in restricted >>>> >>>> >>>> >>>> >>>> >>>> exec ccode in environment >>>> File "D:/web2py/applications/**calcte**st/controllers/default.**py" >>>> <http://127.0.0.1:8000/admin/default/edit/calctest/controllers/default.py>, >>>> line 88, in <module> >>>> >>>> >>>> >>>> >>>> >>>> File "D:\web2py\gluon\globals.py", line 193, in <lambda> >>>> >>>> >>>> >>>> >>>> >>>> self._caller = lambda f: f() >>>> >>>> >>>> >>>> >>>> >>>> File "D:/web2py/applications/**calcte**st/controllers/default.**py" >>>> <http://127.0.0.1:8000/admin/default/edit/calctest/controllers/default.py>, >>>> line 16, in t >>>> >>>> >>>> >>>> >>>> >>>> db.test.c12, >>>> File "D:\web2py\gluon\dal.py", line 9754, in select >>>> >>>> >>>> >>>> >>>> >>>> return adapter.select(self.query,fiel****ds,attributes) >>>> >>>> >>>> >>>> >>>> >>>> File "D:\web2py\gluon\dal.py", line 2218, in select >>>> >>>> >>>> >>>> >>>> >>>> return super(SQLiteAdapter, self).select(query, fields, attributes) >>>> >>>> >>>> >>>> >>>> >>>> File "D:\web2py\gluon\dal.py", line 1665, in select >>>> >>>> >>>> >>>> >>>> >>>> sql = self._select(query, fields, attributes) >>>> >>>> >>>> >>>> >>>> >>>> File "D:\web2py\gluon\dal.py", line 1520, in _select >>>> >>>> >>>> >>>> >>>> >>>> sql_f = ', '.join(map(geoexpand, fields)) >>>> >>>> >>>> >>>> >>>> >>>> File "D:\web2py\gluon\dal.py", line 1517, in geoexpand >>>> >>>> >>>> >>>> >>>> >>>> if isinstance(field.type,str) and >>>> field.type.startswith('**geometr**y'): >>>> >>>> >>>> >>>> >>>> AttributeError: 'FieldVirtual' object has no attribute 'type' >>>> >>>> >>>> >>>> >>>> 2013/2/26 Massimo Di Pierro <[email protected]> >>>> >>>> This helped me a lot. I included these defaults in web2py so that you >>>>> should need to do it yourself. Can you please check if >>>>> >>>>> db.test.c12 = Field.Virtual (lambda r: r.t1+r.t2) >>>>> >>>>> now works as expected? >>>>> >>>>> On Tuesday, 26 February 2013 05:28:59 UTC-6, Donatas Burba wrote: >>>>>> >>>>>> I have a workaround for this issue. Just a little helper function in >>>>>> modules: >>>>>> >>>>>> def virtual_field(db, table_name, field_name, field_type, >>>>>> compute=lambda row: None, label='', represent=None): >>>>>> db[table_name][field_name] = Field.Virtual(compute) >>>>>> db[table_name][field_name].**typ****e = field_type >>>>>> db[table_name][field_name].**lab****el = label >>>>>> db[table_name][field_name].**rep****resent = represent >>>>>> db[table_name][field_name].**for****matter = lambda value: value >>>>>> db[table_name][field_name].**com****ment = None >>>>>> db[table_name][field_name].**rea****dable = True >>>>>> db[table_name][field_name].**wri****table = False >>>>>> db[table_name][field_name].**req****uires = None >>>>>> db[table_name][field_name].**wid****get = None >>>>>> db[table_name][field_name].**nam****e = field_name >>>>>> db[table_name][field_name].**tab****lename = table_name >>>>>> db[table_name][field_name].**fil****ter_out = None >>>>>> >>>>>> Because I very often need such virtual fields (to show complex >>>>>> computed result from several fields or even tables), this really helps >>>>>> me. >>>>>> >>>>> -- >>>>> >>>>> >>>> -- >>> >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "web2py-users" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to web2py+un...@**googlegroups.com. >>> >>> For more options, visit >>> https://groups.google.com/**groups/opt_out<https://groups.google.com/groups/opt_out> >>> . >>> >>> >>> >> >> -- > > --- > You received this message because you are subscribed to the Google Groups > "web2py-users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. > > -- --- You received this message because you are subscribed to the Google Groups "web2py-users" group. 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