In case you care, here's the table structure that the Everything Chatterbox system uses: 
CREATE TABLE message (
  message_id int(11) DEFAULT '0' NOT NULL auto_increment,
  msgtext char(255) DEFAULT '' NOT NULL,
  author_user int(11) DEFAULT '0' NOT NULL,
  tstamp timestamp(14),
  for_user int(11) DEFAULT '0' NOT NULL,
  PRIMARY KEY (message_id),
  KEY for_user (for_user)
);

[download]

This basically breaks down to:

  • message_id -- arbitrary AUTO_INC primary key
  • msgtext -- 255 chars of communication
  • author_user -- reference to authors's unique ID
  • tstamp -- timestamp set on insertion of message, used for ordering
  • for_user -- optional field, if left blank it's considered "chat" if set, it becomes a "message" for whatever user ID it references

    For chat, your sql query looks something like: 

      my $expiration_seconds = 500;
  $dbh->prepare("SELECT * FROM message 
     WHERE for_user=0 AND unix_timestamp(now())-unix_timestamp(tstamp)
+ < $expiration_seconds ORDER BY tstamp");

    [download]

    then for viewing a user's specific messages: 

      my $UID = getUserIdSomehow();
  $dbh->prepare("SELECT * FROM message 
     WHERE for_user=$UID ORDER BY tstamp");

    [download]

    It's really a pretty simple system, but it does depend on having numeric IDs that you can look up your users with. And don't worry too much about running out of INT -- 32-bits gives you lots of room to talk.

    -nate

    In reply to Re: Message storing problem. by nate
    in thread Message storing problem. by Martin A

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