MySQL date_add
Here's a quick MySQL tip I wanted to throw your way. I created an event system a while back and one of the requirements of the system was to show events that happened yesterday forward, meaning events older than 2 days were to be hidden. MySQL's date_add will allow you to do just that:
The MySQL Example
SELECT title, venue, url, city, state, DATE_FORMAT(date_starts,\'%b %e\') as formatted_date
FROM events
WHERE date_starts >= DATE_ADD(NOW(), INTERVAL -1 DAY) // yesterday!
ORDER BY date_starts ASC
Note that I'm using a negative date value. You can use a positive date value to get tomorrow, next week, next month, etc..
I like the idea of showing events the from past few days -- they show that there's been action recently. Click here for more about MySQL date_add.
![Introducing MooTools Templated]()
One major problem with creating UI components with the MooTools JavaScript framework is that there isn't a great way of allowing customization of template and ease of node creation. As of today, there are two ways of creating:
new Element Madness
The first way to create UI-driven...
![39 Shirts – Leaving Mozilla]()
In 2001 I had just graduated from a small town high school and headed off to a small town college. I found myself in the quaint computer lab where the substandard computers featured two browsers: Internet Explorer and Mozilla. It was this lab where I fell...
![Retrieve Your Gmail Emails Using PHP and IMAP]()
Grabbing emails from your Gmail account using PHP is probably easier than you think. Armed with PHP and its IMAP extension, you can retrieve emails from your Gmail account in no time! Just for fun, I'll be using the MooTools Fx.Accordion plugin...
![MooTools Zebra Tables Plugin]()
Tabular data can oftentimes be boring, but it doesn't need to look that way! With a small MooTools class, I can make tabular data extremely easy to read by implementing "zebra" tables -- tables with alternating row background colors.
The CSS
The above CSS is extremely basic.
Or you can do it like this: date_starts >= NOW() – INTERVAL 1 DAY
Easier to read in my opinion :) Good tip! I do it like this quite often
I prefer using php function strtotime() because queries using MySQL functions like NOW() can’t be cached
@macol: Ohhhh, good tip!
Hmm good tip indeed, but… The queries still cannot be cached if you use something as dynamic as strtotime(‘now’), isn’t that right?
So using strtotime() does not enable the query to be cached? Or am I wrong?
strtotime() would only give you an advantage if the same query is run during the same second?
If you want caching to work, you can truncate the time part like this:
$yesterday = strtotime('-1 day'); $yesterday_str = date('Y-m-d 00:00:00', $yesterday);Then it’ll be good for the whole day. This has the added benefit of matching the logical meaning of “yesterday” rather than being precicely 24 hours ago.
@Jeremy Parrish: Why didnt I think of this? :) Thanks!
This query will not be used index.
@Niklas Berglund: your query must be deterministic – query might provide same result no matter how many times it is run, if data remains the same. So if your query uses non-deterministic functions such as NOW(), UUID(), RAND(), CONNECTION_ID() etc it will not be cached.
However, if you pass in a fixed value from PHP as in
SELECT * FROM logs WHERE logstamp = ”
it will be cached.
(the php function today() is just a one-liner that returns the current day in mysql format)
@Metric Stormtrooper: SELECT * FROM logs WHERE logstamp = ‘::php today() ::’
hm, cant post php syntax here, but you get the idea
Or you can use this: DATE_SUB(NOW(), INTERVAL 1 DAY)