In this section, you'll see more highlights of new functionality that will be introduced in MySQL 4.1. This list is not the full list of changes; for that, you can read the actual changelog entries at http://dev.mysql.com/doc/en/News-4.1.x.html.
Speed enhancements. As if MySQL weren't fast enough, the developers are always finding ways to make it even faster.
Table creation using LIKE. You can use CREATE TABLE tablename LIKE othertablename to create a new table with the exact structure (but no data) as an existing table.
Usability enhancements, primarily a help system within the MySQL command-line interface. Typing UCASE will provide help for the UCASE() MySQL function, for example.
DATE/DATETIME usage will be changing slightly, in that you will no longer be able to enter data in the format of YYYYMMDD HHMMSS instead of YYYY-MM-DD HH:MM:SS; all the separators must be used.
TIMESTAMP will be returned as a string in the YYYY-MM-DD HH:MM:SS format, instead of in microseconds.
Numerous date and time functions have been added, and existing ones enhanced. On the "Date and Time Functions" page of the MySQL manual (http://dev.mysql.com/doc/mysql/en/Date_and_time_functions.html) these functions are noted as new for version 4.1.x.
You will be able to specify a length for BLOB and TEXT fields, and by doing so, MySQL will autmatically change it to its appropriate type.
Per-column comments can now be added, and SHOW FULL COLUMNS FROM tablename will display these comments.
Spatial extensions will be available to allow the generation, storage, and analysis of geographic features. You can read all about this topic at http://dev.mysql.com/doc/en/Spatial_extensions_in_MySQL.html.
With the exception of the date-related changes mentioned earlier, none of these listed enhancements to MySQL are incompatible with previous versions. In the changelog for minor and major releases, MySQL AB will always publish a warning statement, in bold lettering, to indicate when an incompatibility is caused by a new feature.