mysql temporary tables May 28, 2008
Posted by chris in : SQL , add a commentTemporary tables exist in memory and are great if you just want to create a quick data store for the life of your current database connection. MySQL will purge the temporary table from memory at the end of the database connection. For a temporary table that persists and can be used by multiple connections you will need to create a Heap table.
CREATE TEMPORARY TABLE cancelledOrders ENGINE=MEMORY SELECT * FROM my_table
More information on temporary and heap tables
modifying tables using javascript and dom May 27, 2008
Posted by chris in : ajax/dom/javascript , add a comment
var tbl = document.getElementById('table');
var row = tbl.getElementById('tr');
var cell = row.getElementsByTagName('td');
cell[0].innerHTML='cell 0';
cell[1].innerHTML='cell 1';
cell[2].innerHTML='cell 2';
use linux screen command to manage multiple shell sessions May 27, 2008
Posted by chris in : linux , add a commentScreen is useful for running a script or other long process as yourself if you are worried about disconnecting from your SSH session or want to do some other things in the shell as the process runs. You will need screen installed to do this. This will really save you a lot of time with Linux servers.
To start a screen session:
screen -R -D
To detatch from the screen session and continue working from the shell:
Ctrl + a + d
To view the status of your screen sessions:
screen -ls
To reattach an existing screen session:
screen -r screen name
You can get the screen name via the screen -ls command, the screen name should look something like 3003.pts-4.localhost.
mysql date/time functions May 12, 2008
Posted by chris in : SQL , add a commentBetter than using PHP to time format date times stored in your database for easier human readability is using MySQLs built in functions:
To turn a date time stamp into a readable time on the 12 hour clock with an AM/PM signifier
TIME_FORMAT(date_time,’%h:%I:%l %p’) as time
Returning just the date time portion of date time stamp
DATE(date_time) as date
Make a date pretty
Unlike the actual dates I go on, in MySQL you can actually make her pretty, the following code would convert 2008-01-01 into Jan 01, 2008.
DATE_FORMAT(tour.date_time,’%b %d, %Y’) as date
http://dev.mysql.com/doc/refman/5.0/en/date-and-time-functions.html