NYCPHP Meetup

[Jim Hendricks(Biz Computing)]

The other reason for avoiding this is my Host Provider would croak if I 
build too much in memory thus hogging the memory shared across many 
sites.  I avoid as much memory use as I can so when I really need it 
it's available.

Jim

Adam Fields wrote:

>On Wed, Oct 16, 2002 at 04:22:11PM -0400, Jim Hendricks wrote:
>  
>
>>Adam Fields wrote:
>>
>>    
>>
>>>I'd wrap a class around the whole thing. Use that class to broker
>>>reads and writes to the tree table. Add a "changed" timestamp to the
>>>tree, and have a read from the class only reload the tree from the
>>>database if it's changed since the last read. Stash the object in the
>>>session for reuse, or serialize it to another table (or file, or
>>>whatever) for quick retrieval.
>>> 
>>>
>>>      
>>>
>>I don't know about the class thing since it adds a level of complexity 
>>to the code that I don't know
>>if it's waranted.  
>>    
>>
>
>I would argue that this will actually make the majority of your code
>simpler, because you're encapsulating the complexity. :)
>
>I'm the first to admit that classes aren't appropriate for everything,
>but they're the right approach for this kind of stuff.
>
>I'd do something like this:
>
>class tree {
>      var nodemap;
>      # and whatever else you want
>
>      function tree () {
>      # maybe some init code
>      }
>
>      function get_tree () {
>      # check if tree has changed or isn't populated yet
>      # if yes to either, get tree from db
>      # otherwise, maybe get tree from intermediate storage if you're
>      doing that
>
>      }
>
>      function save_tree () {
>      # write tree to db
>      }
>
>      function store_tree () {
>      # write tree to intermediate storage
>      }
>
>      function render_tree () {
>      # if tree isn't populated, get tree
>      # output tree html or tree values or whatever
>      }
>      
>      function get_tree_values () {
>      # return raw node data for the tree
>      }
>}
>
>Then, in your page:
>
>$mytree = new tree();
>$mytree->render_tree();
>or
>$mytree->get_tree_values();
>
>  
>
>>I do like the idea of caching the tree though.  I 
>>would cache it in the DB so that the
>>tree does not need to be generated at all when the request to display it 
>>occurs.  The tree would
>>be regenerated everytime a change occurs to the underlying data ( which 
>>is a low volume data set )
>>This may not be a good idea for items that have a higher change velocity.
>>    
>>
>
>While I wouldn't advocate this approach for something that changes
>once a minute or so, if it changes less than once an hour, this will
>probably still result in a performance gain, and it will be easier to
>maintain.
>
>  
>