the technical content of grant horwood
06
May
2024

mysql: using the slow query log

the cold, hard truth is that the reason your web app or api is running slow is because of your database calls. you can migrate everything to frakenphp or put compression in your http server if you want, i’m not going to stop you, but if you want to shave whole seconds off your response times, you should take a hard look at all that janky sql and yolo orm queries you wrote.

the good news is that mysql has a tool to find and log your slow queries. it’s called the ‘slow query log’, basically the perfect name, and it comes pre-installed. let’s get it turned on, set up, and look at the output.

a developer discovering they’re really bad at writing sql
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Posted by gbhorwood in mysql, 0 comments
29
Apr
2024

managing disk space in bash

a week ago, i ran this db insert-heavy script on a server and forgot to turn off mysql‘s binlog feature first. the result, of course, is that i filled up the disk in about three minutes and brought the whole server down. not great for a tuesday. fortunately, finding and fixing the problem was straightforward. the downtime was only a couple of minutes.

in this post we’re going to go over inspecting our disk space; figuring out how much we have left and finding out what we spent all those blocks on. we’ll look at three basic tools:

df for inspecting disk space
du for getting directory sizes
find for finding files to delete these all come pre-packaged with your linux or linux-like operating system, so put that apt back in your pocket.

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Posted by gbhorwood in linux, 0 comments
22
Apr
2024

uploading to s3 with bash

s3 is handy and useful, but it would be a lot more handy and useful if we had a shell script for pushing things to buckets; a script that didn’t require a special cli tool. something portable that we could add to existing scripts or throw in a cron job or distribute to our friends. a script that we could tell “put this file in this bucket” and it would just do that. that would be a good thing. let’s build that.

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Posted by gbhorwood in aws, linux, 0 comments
18
Apr
2024

making mysql STDOUT less (or more) of a mess

you’re doing some command line mysql work, something like piping in a query to mysql and dumping the output to STDOUT. what you want, of course, is some nicely-formatted output. what you get, instead, is hot trash like this:

$ echo "SELECT * FROM albums" | mysql record_collection_db
id  artist  tite
1   Bratmobile  Pottymouth
2   Coltrane, John  Giant Steps

fortunately, mysql has some built-in formatters to help the world make sense again.

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Posted by gbhorwood in mysql