Buck Nuggets wrote: > 1. mysql doesn't support transactions - one of its io layers (innodb) > does. If you're hoping to get your application hosted you will find > that most mysql installations don't support innodb. And due to the > bugs in mysql, when you attempt to create a transaction-safe table in > mysql if innodb isn't available it will just silently create it in > myisam, and your transactions will be silently ignored.
That's not a bug; it's an explicitly-stated design choice. http://dev.mysql.com/doc/mysql/en/create-table.html If a storage engine is specified that is not available, MySQL uses MyISAM instead. > 2. mysql is still missing quite a few database basics - views are the > most amazing omission, but the list also includes triggers and stored > procedures as well. Although most of these features are included in > the new beta, they aren't yet available in production. Views, triggers, stored procedures are all available in 5.0.2 (beta). > 3. mysql has an enormous number of non-standard features such as > comment formatting, how nulls work, concatenation operator, etc. This > means that you'll learn non-standard sql, and most likely write > non-portable sql. SET GLOBAL sql_mode='ansi'; and you won't have to worry about it. > 4. additionally, mysql has a peculiar set of bugs - in which the > database will change your data and report no exception. These bugs > were probably a reflection of mysql's marketing message that the > database should do nothing but persist data, and data quality was the > responsibility of the application. This self-serving message appears > to have been dropped now that they are catching up with other products, > but there's a legacy of cruft that still remains. Examples of these > errors include: silent truncation of strings to fit max varchar > length, allows invalid dates, truncation of numeric data to fit max > numeric values, etc. MySQL gives warnings when data is truncated or misformatted. http://dev.mysql.com/doc/mysql/en/mysql-info.html http://dev.mysql.com/doc/mysql/en/mysql-warning-count.html http://dev.mysql.com/doc/mysql/en/show-warnings.html Since we're in comp.lang.python, MySQLdb-1.2 uses the warnings module to alert you to this. MySQLdb-1.0 and earlier would raise a Warning exception (or not, if you used a different cursor class). Implicit default column values can disabled in 5.0.2 by running the server in strict mode. http://dev.mysql.com/doc/mysql/en/server-sql-mode.html > 5. cost: mysql isn't expensive, but it isn't free either. Whether or > not you get to use it for free depends on how you interpret their > licensing info and faq. MySQL's recommendation if you're confused (and > many are) is to license the product or call one of their reps. MySQL is licensed under the GPL. You can buy a commercial license if you don't want the GPL's restrictions. http://www.mysql.com/company/legal/licensing/ > Bottomline - mysql has a lot of marketshare, is improving, and I'm sure > that it'll eventually be a credible product. But right now it's has a > wide range of inexcusable problems. It's not a bug if you didn't RTFM. -- http://mail.python.org/mailman/listinfo/python-list
