Skip to main content

database design for tracking the location. NEED HELP!! :(



im currently doing the database design for an android app like friend finder. im doing the coding in java and i'l be using google maps to display the location. location is tracked using gps. the functionality would be:








-locate u n all ur friends on the map


-give alerts when a friend is somewhere close like within 5km


-hide users location from certain people.


this is what ive come up with so far..








location

----------

location id

location name



user

---------

user id

and rest of the details



friendlist

------------

userid

friendid

distance_frm_user

users_location [visible, nt visible]

type [friend, rejected]







if the user accepts a friend request then 2 rows r created in the friendlist table


one with userid=1 and friendid=2


second with userid=2 and friendid=1


and the attribute "type" in the friendlist wud be set to friend for both the rows in the friendlist table.






users_location is set to visible if the user wants that friend to see his location.






my questions are:


-do i need to a map entity if yes then what would be the relation between the map entity and the location entity?


-do i need to provision users_location in the location table? if yes i dnt have a clue hw i can do that.


-are the tables correct? or am i forgetting something.





P.S: This is the first time im doing this.


Comments

Popular posts from this blog

Why is this Javascript much *slower* than its jQuery equivalent?

I have a HTML list of about 500 items and a "filter" box above it. I started by using jQuery to filter the list when I typed a letter (timing code added later): $('#filter').keyup( function() { var jqStart = (new Date).getTime(); var search = $(this).val().toLowerCase(); var $list = $('ul.ablist > li'); $list.each( function() { if ( $(this).text().toLowerCase().indexOf(search) === -1 ) $(this).hide(); else $(this).show(); } ); console.log('Time: ' + ((new Date).getTime() - jqStart)); } ); However, there was a couple of seconds delay after typing each letter (particularly the first letter). So I thought it may be slightly quicker if I used plain Javascript (I read recently that jQuery's each function is particularly slow). Here's my JS equivalent: document.getElementById('filter').addEventListener( 'keyup', function () { var jsStart = (new Date).getTime()...

Is it possible to have IF statement in an Echo statement in PHP

Thanks in advance. I did look at the other questions/answers that were similar and didn't find exactly what I was looking for. I'm trying to do this, am I on the right path? echo " <div id='tabs-".$match."'> <textarea id='".$match."' name='".$match."'>". if ($COLUMN_NAME === $match) { echo $FIELD_WITH_COLUMN_NAME; } else { } ."</textarea> <script type='text/javascript'> CKEDITOR.replace( '".$match."' ); </script> </div>"; I am getting the following error message in the browser: Parse error: syntax error, unexpected T_IF Please let me know if this is the right way to go about nesting an IF statement inside an echo. Thank you.