MySQL query comments in Rails
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MySQL query comments in Rails
1–10 of 21 posts
Re: MySQL query comments in Rails
#2I've been doing this on high traffic PHP sites for years. It makes mytop very informative and easy to understand, and I even occasionally use them for cheapo memcache caching instructions (built into db layer) when it's not worth precaching or coming up with a more sophisticated scheme. Highly recommended.
One difference though: I prepend the comment instead of appending it.
Re: MySQL query comments in Rails
#3I dig this, a lot. Anyone know if there's a Django equivalent yet? If not, I know what I'll be doing with at least one evening this week...
Re: MySQL query comments in Rails
#4Note that adding comments to otherwise identical queries will typically cause the MySQL query cache to not realize they are the same. See: http://www.mysqlperformanceblog.com/2008/03/20/mysql-query-c...
Otherwise, neat idea, I like it.
Re: MySQL query comments in Rails
#5Does Rails not have an equivalent to the Django-Debug-Toolbar to easily debug stuff like this in development?
As for production, going with a fleshed-out service like NewRelic makes more sense to me. If I see slow queries start happening I'd want a broader report of what's going on in my system, not just a map of the query to a controller/action.
Re: MySQL query comments in Rails
#6Note that adding comments to otherwise identical queries will typically cause the MySQL query cache to not realize they are the same. See: http://www.mysqlperformanceblog.com/2008/03/20/mysql-query-c... Otherwise, neat idea, I like it.
Most, if not all production mysql installations have this cache disabled anyways. (Based on my experience at Engine Yard for 3 years and other places the last 5 years.)
Re: MySQL query comments in Rails
#7I dig this, a lot. Anyone know if there's a Django equivalent yet? If not, I know what I'll be doing with at least one evening this week...
Django debug toolbar can show you where awk/grep queries are called
Re: MySQL query comments in Rails
#8Note that adding comments to otherwise identical queries will typically cause the MySQL query cache to not realize they are the same. See: http://www.mysqlperformanceblog.com/2008/03/20/mysql-query-c... Otherwise, neat idea, I like it.
Most, if not all production mysql installations have this cache disabled anyways. (Based on my experience at Engine Yard for 3 years and other places the last 5 years.)
Why?
Re: MySQL query comments in Rails
#9I dig this, a lot. Anyone know if there's a Django equivalent yet? If not, I know what I'll be doing with at least one evening this week...
Django debug toolbar can show you where awk/grep queries are called
Right, but that's a totally different solution. It only tells when I ask it, and it doesn't work for any query not issued in a rendered view (most of our data access is AJAX). I like the 37s solution because I can leave it running on a system and then find stack information in the slow query log later on.
Re: MySQL query comments in Rails
#10I dig this, a lot. Anyone know if there's a Django equivalent yet? If not, I know what I'll be doing with at least one evening this week...
Playfire has released something that will tack a comment onto all your queries for you: https://github.com/playfire/django-append-url-to-sql/