There are a number of features in MySQL which are important for some users, but worse than un-necessary for others - they make for reduced performance, and make for larger executable files.

In order to meet the requirements of both groups of users, two different binary versions of MySQL are available for download - MySQL and MySQL - Max.   A single set of source code covers both versions, as the extras are selected through compile time options.

The extra features in the "max" version include
                                     Berkeley_DB i(BDB) tables
                                     InnoDB tables
both of which provide transaction-safe tables (i.e. tables to which locks can be applied while a series of SQL queries is made, the total of that series of queries being referred to as a transaction).

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