This is a convention in the framework that the primary key be called "_id", used by "simplified" adapter classes to make life easier for the developer.
-- Kostya Vasilyev -- http://kmansoft.wordpress.com 07.12.2010 1:33 пользователь "Ashish" <[email protected]> написал: > Well as per my understanding.... it is of utmost importance to have > _id column in android sqlite database. > This is the default way of making each record unique in its nature... > so, even if you don't use any primary key, ur records won't be > duplicate. > > > Regards, > Ashish > > On Dec 3, 1:31 pm, "Jonas Petersson" <[email protected]> wrote: >> On 12/03/2010 09:04 AM, pramod.deore wrote: >> >> > When I tried this as >> > [...] >> > Cursor c = sampleDB.rawQuery("SELECT RoomID as _id FROM " >> > +ROOM_TABLE_NAME, null); >> > [...] >> > new String[] {"RoomID"}, >> > [...] >> > java.lang.IllegalArgumentException: column 'RoomID' does not exist >> >> Yes, that is to be expected, you have just "renamed" the RoomID column >> to "_id" so obviously you must also access it that way (or ALSO select >> it under the original name, but that would be confusing IMHO). >> >> / Jonas >> >> > On Dec 3, 12:51 pm, "Jonas Petersson"<[email protected]> wrote: >> >> Um, you might try something like "select RoomID as _id ..." >> >> >> Best / Jonas >> >> >> On 12/03/2010 08:40 AM, Kumar Bibek wrote: >> >> >>> You cannot in this case. This is a mandatory requirement. >> >> >>> "pramod.deore"<[email protected]> wrote: >> >> >>>> Hi Bibek, Thanks for reply. But my table RoomTable have only three >> >>>> columns, RoomID, RoomName, and RoomSuffix. It doesn't have _id field. >> >>>> Then how to use Cursor Adapter here. >> >> >>>> On Dec 3, 11:55 am, Kumar Bibek<[email protected]> wrote: >> >>>>> Cursor Adapters require the table to have a _id field. Else, you would get >> >>>>> this exception. >> >>>>> Kumar Bibekhttp://techdroid.kbeanie.comhttp://www.kbeanie.com > > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected]<android-developers%[email protected]> > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
