A place to put my thoughts…
Since I can never remember the syntax to add a column to a table, here it is:
alter table foo_tablename add column foo_column int(10) default null
alter table – the actual commandfoo_tablename – the table name we’re alteringadd column – telling sql to add a column instead of some other alterationfoo_column – name of the column to addint(10) default null – the column’s qualities (it’s an int up to 10 digits long, can be null and defaults to nullPeople leave their macs unlocked. When they do, punish them in the most humane way possible =D
Here are some of my favorites (setting a crontab is as easy as crontab -e
Have their computer open their gmail inbox every 30 minutes. It’ll feel pretty random at first:
1 | */30 * * * * ( /usr/bin/open "https://mail.google.com/mail/?tab=wm#inbox" ) |
Or… every ten minutes, have their speakers verbalize something childish (yet HILARIOUS):
1 | */10 * * * * ( /usr/bin/say "Peepee" ) |
atat is a great little program. If you have a little time to work, feel free to create a bash script to do your bidding, then queue it as a job using at =]
Sometimes MySQL performance can be difficult to hammer out. One of the quickest ways to get a good gut check is to have a look at the current process list. Check this out:
1 2 3 4 5 6 7 8 9 10 | mysql> show processlist; +-------+------+-----------+------------+---------+------+----------+------------------+ | Id | User | Host | db | Command | Time | State | Info | +-------+------+-----------+------------+---------+------+----------+------------------+ | 14302 | abcd | localhost | rohjay_one | Sleep | 3696 | | NULL | | 14958 | abcd | localhost | NULL | Query | 0 | starting | show processlist | +-------+------+-----------+------------+---------+------+----------+------------------+ 2 rows in set (0.00 sec) mysql> |
Now, this is relatively uninteresting, but sometimes, you’ll find a list of active queries that have stacked up against your db. Some things that can really help you identify issues is by ensuring each different piece of your platform identifies itself uniquely.
Once that happens, you can see which queries from where are hanging on. Parts of your platform can stall and hold onto connections, queries can take an eternity, bad code can hold result sets in memory, etc… This should give you a good idea where to start looking!
Hope this helps =]