[nycphp-talk] Need help understanding NULL

Andy Dirnberger dirn at
Sat Aug 29 16:41:57 EDT 2009

On Sat, Aug 29, 2009 at 4:33 PM,
lists at<lists at> wrote:
> If anyone else has practical examples, please don't hold back.

Here's an example of one instance in which I use null.

Before querying the database, I check to see if the result of the
query has been cached.  I call a function that will either return the
value in the cache or null, either because the cache has expired or
because it was never set.  When I receive a return value other than
null, I skip the database query.  When null comes back, I query the
database and update the cache.

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