Since MySQL 4.0, the free (in the sense of GPL) and commercial versions have different names. Here they are:
|MySQL Standard Community Edition||GPL||All default functions that can be considered stable (including InnoDB)|
|MySQL Max Community Edition||GPL||Same as MySQL Standard, but with additional functions and table drivers that have not reached full maturity|
|MySQL Classic||commercial||Like MySQL Standard, but without InnoDB|
|MySQL Pro||commercial||Like MySQL Standard, but with InnoDB (thus with transactions)|
|MySQL Pro Certified Server||commercial||Like MySQL Pro, but usable only in the context of the Certified Server program MySQL Network and optimized for maximum stability and security|
For ordinary GPL applications, the use of the Standard version is recommended. The additional functions in the Max version are for use only in special applications. Currently (version 5.0), the Standard and Max versions differ in the support of BDB tables and the SSL encryption of client/server connections. These functions will be incorporated into the Standard and commercial versions only when they are considered sufficiently stable. You can determine which functions the running version of MySQL supports with the SQL command SHOW VARIABLES. In the following code you can see the results of MySQL Standard 5.0.2.
mysql> SHOW VARIABLES LIKE 'have%'; Variable_name Value have_archive NO have_bdb NO have_compress YES have_crypt YES have_csv NO have_example_engine NO have_geometry YES have_innodb YES have_isam NO have_ndbcluster NO have_openssl NO have_query_cache YES have_raid NO have_rtree_keys YES have_symlink YES
In the case of commercial applications, the decision between Classic and Pro depends simply on whether InnoDB is needed. (The license for the Pro version is more expensive.) The Classic and Pro versions cannot be simply downloaded at www.mysql.com, but are provided only after a license has been issued.
MySQL Pro Certified Server has been available only since the beginning of 2005, as part of the program MySQL Network. MySQL promises users of this program particularly stable and secure versions. If you wish to know which server version is being run, then execute the following SQL command:
mysql> SHOW VARIABLES LIKE 'version'; Variable_name Value__________ . version 5.0.2-alpha-standard
This output shows that the Standard version 5.0.2 is running. There is no additional Max functionality and no license for commercial use.
Note: Do not confuse MySQL Max with MaxDB. The latter is the former SAP-DB database system that since 2004 has been maintained and sold by the MySQL firm. There are indeed similarities between the database systems MySQL and MaxDB, but there are considerable differences. This book is strictly about MySQL, not MaxDB.
Regardless of whether you are using a commercial or GPL version of MySQL, you may take out a support contract with MySQL. You thereby simultaneously support the further development of MySQL.
Tip: Details on commercial MySQL licenses and paid support can be found at https://www.mysql.com/support/. Links to various companies that offer commercial MySQL support can be found at http://solutions.mysql.com.
The above tip is excerpted from from Chapter 1, "What is MySQL?" of The Definitive Guide to MySQL 5 by Michael Kofler, courtesy of Apress. Find it helpful? Purchase the book here.
About the author: Michael Kofler holds a Ph.D. in computer science from Graz Technical University. He has written a number of successful computer books on topics such as Visual Basic, Visual Basic .NET, and Linux. Michael is the author of The Definitive Guide to MySQL 5, Third Edition and Definitive Guide to Excel VBA, Second Edition from Apress.