Mysql – Informix to MySQL Conversion

MySQL does use MVCC if your tables are in InnoDB format, which they should be unless you have a specific reason to use MyISAM. There are pros and cons for both. If your primary concern is data-size, MySQL offers several plugins, one of which is compressed MyISAM tables, which can make the data-size very small.

When picking one or the other, you should examine your complete use case before making a selection. Data-size is one factor, but it really depends on your usage. If it's for a web-based service of sorts, MySQL is usually a good candidate as it performs well with read-intensive workloads (which most websites are). MySQL also supports replication inherently (albeit asynchronously). If it's something more specific, Postgres may be a better option.

You should also take a close look at Percona's MySQL Server (http://www.percona.com/software/percona-server/). It's based off MySQL and offers a HUGE performance improvement over the standard MySQL builds. It's very well supported and constantly being improved. My feeling is that Percona MySQL Server will probably meet your requirements.

Hope this helps!

As per comment responses #5 and #11 by Guy Bowerman at his blog

...you'll need to set it in your environment prior to executing the oninit command to start the server (on UNIX). If the server is on Windows, you can also set the variable in the registry under: HKEY_LOCAL_MACHINE\Software\Informix\Online\%INFORMIXSERVER%\Environment

The fix is to change both CLIENT_LOCALE from the default "EN_US.CP1252" and DB_LOCALE from the default "EN_US.8859-1" to "EN_US.UTF8" in the registry.