Posted by Captain Paralytic on 12/21/07 14:01

On 21 Dec, 13:56, Tarscher <tarsc...@gmail.com> wrote:
> On 21 dec, 14:02, Captain Paralytic <paul_laut...@yahoo.com> wrote:
>
>
>
> > On 21 Dec, 12:06, Tarscher <tarsc...@gmail.com> wrote:
>
> > > On 21 dec, 12:52, Captain Paralytic <paul_laut...@yahoo.com> wrote:
>
> > > > On 21 Dec, 11:43, Tarscher <tarsc...@gmail.com> wrote:
>
> > > > > On 21 dec, 12:24, Captain Paralytic <paul_laut...@yahoo.com> wrote:
>
> > > > > > On 21 Dec, 11:18,Tarscher<tarsc...@gmail.com> wrote:
>
> > > > > > > On 21 dec, 12:12, Captain Paralytic <paul_laut...@yahoo.com> wrote:
>
> > > > > > > > On 21 Dec, 10:52,Tarscher<tarsc...@gmail.com> wrote:
>
> > > > > > > > > On 21 dec, 11:45, Captain Paralytic <paul_laut...@yahoo.com> wrote:
>
> > > > > > > > > > On 21 Dec, 10:36,Tarscher<tarsc...@gmail.com> wrote:
>
> > > > > > > > > > > On 21 dec, 11:13, Captain Paralytic <paul_laut...@yahoo.com> wrote:
>
> > > > > > > > > > > > On 21 Dec, 08:43,Tarscher<tarsc...@gmail.com> wrote:
>
> > > > > > > > > > > > > Hi all,
>
> > > > > > > > > > > > > I have events containing attendees (events has many attendees). The
> > > > > > > > > > > > > attendee table tells whether a user will attend the event or not. I
> > > > > > > > > > > > > want to build a query that returns all the different events to a user
> > > > > > > > > > > > > and if he will attend the event or not (or hasn't filled it in yet)
>
> > > > > > > > > > > > > the returned result could be something like:
>
> > > > > > > > > > > > > event.id attendees.user_id attendee.present
> > > > > > > > > > > > > 1 1 0
> > > > > > > > > > > > > 2 1
> > > > > > > > > > > > > 3 1 1
>
> > > > > > > > > > > > > Please note that attendee.present can be null if the user didn't yet
> > > > > > > > > > > > > tell if he would come to the event.
>
> > > > > > > > > > > > > Can this be done?
>
> > > > > > > > > > > > > thanks
> > > > > > > > > > > > > Stijn
>
> > > > > > > > > > > > And this has what to do with php?
>
> > > > > > > > > > > > You would be better to ask this in a database group.
>
> > > > > > > > > > > > However some questions:
> > > > > > > > > > > > If a user is querying the database to find if he will be attending the
> > > > > > > > > > > > event, why does his own ID need to be present in the output?
> > > > > > > > > > > > How does the attendee's id get into the table against an event in the
> > > > > > > > > > > > first place?
>
> > > > > > > > > > > I indeed don't need the user_id since it is stored in the session. It
> > > > > > > > > > > was just to clarify that the query need to return 1 user.
>
> > > > > > > > > > > Via the session the user_id stored in the session.
>
> > > > > > > > > > > Regards
>
> > > > > > > > > > I don't understand how
> > > > > > > > > > "Via the session the user_id stored in the session."
>
> > > > > > > > > > answers the question
> > > > > > > > > > "How does the attendee's id get into the table against an event in the
> > > > > > > > > > first place?"
>
> > > > > > > > > sorry, a typo
>
> > > > > > > > > INSERT INTO attendee (event_id, user_id) VALUES ($event_id,
> > > > > > > > > session['user_id'])
>
> > > > > > > > > I get the event_id via the url since the user does this per event.
> > > > > > > > > eg
> > > > > > > > > event1: 'will attend' 'will not attend'
> > > > > > > > > event2: 'will attend' 'will not attend'
>
> > > > > > > > > The 'will attend' and 'will not attend' links point to the sql query
> > > > > > > > > inserting in attendee
>
> > > > > > > > > I hope this helps
>
> > > > > > > > No, that is not what I mean.
>
> > > > > > > > You have a table attendee which contains events. Personally I would
> > > > > > > > have an events table to contain the events.
>
> > > > > > > > Now you tell us that the attendee table has events and attendees and
> > > > > > > > it is possible for an attendee to say that they will not attend the
> > > > > > > > event. I have to say that someone who will not attend an event will by
> > > > > > > > definition not be an attendee!
>
> > > > > > > > My question is, if for some reason you have all your events listed in
> > > > > > > > the attendee table and the attendee has not put in there a record
> > > > > > > > saying that he will or will not attend the event, how did the record
> > > > > > > > with the event id and attendee id get in the table in the first place?
>
> > > > > > > I have an event table and attendee table (events has many attendees).
> > > > > > > The event_id in attendee points to the key of the event table.
> > > > > > > event table: id, name, time
> > > > > > > attendee table, id, user_id, event_id, present
>
> > > > > > Things aren't as stated in your first post.
>
> > > > > > However you STILL haven't answered my question.
>
> > > > > > How does an attendeed get an entry in the attendee table against a
> > > > > > particular event? You have suggested that the entry can be there
> > > > > > before the prospective attendee has looked at the table, so HOW did it
> > > > > > getthere?
>
> > > > > Sorry, I have a hard time understanding your question.
>
> > > > > The attendee can enter because he sees all available events (with
> > > > > attend and not attend link behind): the one he attends, the one he
> > > > > will not attend and the one he hasn't yet voted on (in this case there
> > > > > is no attendee record for that user for that event.)
> > > > > we have 3 cases:
> > > > > - on the list of events the user clicks an event he previously said he
> > > > > would attend to not attend. The attendees present record changes to 0
> > > > > - on the list of events the user clicks an event he previously said he
> > > > > would not attend to attend. The attendees present record changes to 1
> > > > > - on the list of events the user clicks an event he hasn't 'voted' on
> > > > > yet. An attendees record is created in the attendee table
>
> > > > > i hope this helps
>
> > > > This doesn't make much sense to me.
>
> > > > Why have a record in the attendee table if the person will not be an
> > > > attendee?
> > > > Why put a record in the attendee table just because a person has
> > > > looked at the detals of an event from the event table?
>
> > > > Why not just list the events from the event table, LEFT JOINED to the
> > > > attendee table. If there is no entry in the attendee table, the person
> > > > is not yet an attendee. If you really want to have a record in the
> > > > attendees table for people who will certainly not be attendees (this
> > > > seems crazy) then I still don't see why you would want to put an entry
> > > > in there when all the person has done is looked at the event.
>
> > > Cos there is a clear difference between saying you don't attend or
> > > haven't said yet you will or will not attend. This way I can show the
> > > user whether he already entered his attendence for this event. (which
> > > he has to do) It works as a reminder
>
> > A table should not be called attendee, if it contains records of non-
> > attendees. This is confusing to future maintainers.
>
> > > > Why put a record in the attendee table just because a person has
> > > > looked at the detals of an event from the event table?
>
> > > This doesn't happen unless the user himself votes his presense (via
> > > the link)
>
> > If no record is put into this table UNLESS the user votes his presence
> > or absence, how can you have "attendee.present can be null if the user
> > didn't yet tell if he would come to the event."
>
> > I have been asking and asking how this null record gets into the
> > table!
>
> There is a difference between a null record, which means no record at
> all, and a null cell which means a record where a cell (eg
> attendee.present = null). I have always talked about the first case

No record at all is not a NULL record, otherwise there would always be
an infinite number of records in any table, because they weren't there
at all!

You really haven't exlained very well at all what you are doing.

Jeff has told me not to jump to conclusions, but you simply have not
given us the full story!

I think you just need to do a LEFT join between 2 tables, but you
really need to lay out what tables you have and what they hold.

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