Re: Constructing query to display item count based on increments of time

2010-10-07 Thread Johan De Meersman
On Wed, Oct 6, 2010 at 11:15 PM, Hank wrote: > Ok, I can see that. > Oh, I wasn't implying that mine was necessarily better - I didn't even think of doing it that way. I suggested a benchmark because different fuctions might have different execution speeds. Now actually thinking about this, I've

Re: Constructing query to display item count based on increments of time

2010-10-06 Thread Hank
Ok, I can see that. Here's a different approach that gets it down to two function calls and some math.. and the DATE_FORMAT call might not even be needed depending on the actual application. select DATE_FORMAT(start_time, "%Y-%m-%d %h:" ) as dhour, 10*(minute(start_time)%6) as dtime

Re: Constructing query to display item count based on increments of time

2010-10-06 Thread Johan De Meersman
Two people already who suggested a text-based approach vs. my numeric approach. Analysing, my method takes a single function call per record (to_unixtime); Travis' takes 4 (concat, date_format, truncate, minute) and Hank's 3 (concate, left, date_format). Someone feel like benchmarking ? :-D On

Re: Constructing query to display item count based on increments of time

2010-10-06 Thread Hank
Here's what I came up with: select concat(left(DATE_FORMAT(start_time, "%Y-%m-%d %h:%i" ),15),"0") as time, count(*) from table group by time -Hank >> >> How would one go about to construct a query that counts items within an >> increment or span of time, let's say increments of 10 minutes? >>

Re: Constructing query to display item count based on increments of time

2010-10-06 Thread Travis Ard
our_table; -Travis -- From: "Pascual Strømsnæs" Sent: Wednesday, October 06, 2010 4:20 AM To: "[MySQL]" Subject: Constructing query to display item count based on increments of time Hi! How would one go about to construct a query that counts it

Re: Constructing query to display item count based on increments of time

2010-10-06 Thread Johan De Meersman
convert to unixtime, convert your interval to unixtime, creatively combine with integer division to get a base number for each period, group by that and count(). 2010/10/6 Pascual Strømsnæs > Hi! > > How would one go about to construct a query that counts items within an > increment or span of t

Constructing query to display item count based on increments of time

2010-10-06 Thread Pascual Strømsnæs
Hi! How would one go about to construct a query that counts items within an increment or span of time, let's say increments of 10 minutes? Imagine a simple table where each row has a timestamp, and the query should return the count of items occurring within the timespan of a defined period.