I am always for using the right tool for the right job. A lot of time, that tool is Python. I have always had trouble finding solid documentation on using MySQL with Python. There was generally enough to get by, but the more the merrier. Enter MySQL for Python by Albert Lukaszewski. Read the rest of this entry »
Erics Tech Blog Thoughts, musings, and other idealistic (sometimes useful) systems and development hoopla.
Database Read/Write Splitting in Frameworks/ORMs
1 Mar 2010 — ericAlthough one of the primary ideas behind frameworks is to keep things as simple as possible, sometimes they create issues in the long run. What I am about to discuss is something of a luxury problem (as scaling usually is), but it is a problem nonetheless.
When initially starting a project, whether you are using Ruby on Rails (Ruby), Django (Python), CakePHP (PHP), Catalyst (Perl), or any of the other 100s of frameworks in any of the languages out there, the first and most important thing to do is to get it out the door. Once you have done that, it’s time to get users, fix bugs, and add features. After you have done all that and you have a great web app, its time to think scaling. (Yes I realize that I have trivialized this process immensely, but its for a point, I promise).
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When To Use MySQL Cursor Classes In Python
18 Jan 2010 — ericI have been writing a lot of code that has been interacting with MySQL lately. Sometimes I find it easier to work the result set in a dictionary form and other times it is easier with an array. But in order to not break all your code, it is necessary to set a default cursor class that keeps your code consistent. More often than not, I find using using a arrays is easier since I just want quick access to all the retrieved data. I also end up making my SELECT calls while specifying the columns and order of the columns I want returned.
The reason that using cursor classes is handy is because Python doesn’t come with a mysql_fetch_assoc like PHP or selectrow_hashref like Perl’s DBI interface. Python uses cursor dictionaries to bridge this gap. Ultimately your result is the same. But as with Perl and PHP, defaulting to cursor dictionaries isn’t a good idea for larger datasets because of the extra processing time and memory required to convert the data.
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MySQL Error 1033: Incorrect Information in File
5 Jan 2010 — ericIf you’ve ever been plagued by an error 1033 issue in MySQL (replication will show it as well), then I might be able to help you out. The error reads something like, “Incorrect information in file: ‘./mydb/table.frm’. I classify this as another one of MySQLs cryptic error messages. Here is how I determined that this was my problem.
Googling around got me an answer, but I had to read a bunch of different responses to piece together the answer. Essentially this issue (in my case) was a result of the InnoDB engine not loading up when MySQL was restarted. Therefore when MySQL tried to read the frm file (table description) which was written for an InnoDB table with the MyISAM reader, it didn’t like it. Since MyISAM is the fallback engine, it went to that and the table became unusable.
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