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MySQL Gotchas

I've only worked with MySQL a little bit, so I'm not yet comfortable using it for data warehousing. I'll be researching Open Source databases in a lot more detail this spring in advance of a few conferences, with the goal of pumping some large volumes of data into them to see how they handle the usual range of business intelligence tasks. Expect a spate of magazine articles come mid-summer on the results, assuming my hardware is set up in time.

While catching up on some reading I came across this useful page about some of the more annoying features of MySQL. The author doesn't treat these as bugs since they are mostly documented and designed-in behavior. For example:

If no DEFAULT value is specified for a column, MySQL automatically assigns one, as follows. If the column may take NULL as a value, the default value is NULL. If the column is declared as NOT NULL, the default value depends on the column type: (...)

I did not realize that MySQL's treatment of NULL values was as strange as the examples he walks through. Worth a read if you are starting to do any development work with MySQL (not just DW experimentation) and you are already familiar with commercial and standards-compliant databases.

Posted by Mark Wednesday, December 03, 2003 11:14:00 PM | permalink |