Table of Contents
Version 4.1 of the MySQL server includes many enhancements and new features. Binaries for this version are available for download at http://www.mysql.com/downloads/mysql-4.1.html.
Subqueries and derived tables (unnamed views). See Subqueries.
INSERT ... ON DUPLICATE KEY UPDATE ... syntax. This allows you to UPDATE an existing row if the insert would cause a duplicate value in a PRIMARY or UNIQUE key. (REPLACE allows you to overwrite an existing row, which is something entirely different.) See INSERT.
A newly designed GROUP_CONCAT() aggregate function. See Group by functions and modifiers.
Extensive Unicode (UTF8) support.
Character sets can be defined per column, table, and database.
New key cache for MyISAM tables with many tunable parameters. You can have multiple key caches, preload index into caches for batches...
BTREE index on HEAP tables.
Support for OpenGIS spatial types (geographical data). See Spatial extensions in MySQL.
SHOW WARNINGS shows warnings for the last command. See SHOW WARNINGS.
Faster binary protocol with prepared statements and parameter binding. See C API Prepared statements.
You can now issue multiple statements with a single C API call and then read the results in one go. See C API multiple queries.
Create Table: CREATE [TEMPORARY] TABLE [IF NOT EXISTS] table2 LIKE table1.
Server based HELP command that can be used in the mysql command line client (and other clients) to get help for SQL statements.
For a full list of changes, please refer to the changelog sections for each individual 4.1.x release.