To upgrade to 1.3.0, it is highly recommended that you first perform a successful upgrade to 1.2.1.
Backup All Data
It is essential that you backup your existing data before attempting an upgrade. For releases prior to 1.3, the safest way to perform a full backup is:
stop the Alfresco server
backup the database (e.g. export full DB to file)
backup the 'alf_data' directory (you could copy the DB export file into it first)
Installing from 1.2.1 to 1.3.0
There is a database schema change as part of improvements to 1.3.0. To ensure the most successful upgrades, this schema change is not made automatically on deployment of the 1.3 Alfresco application. A database script will need to be run prior to deploying the new application - you will need to ensure that you apply the appropriate script for the database that you are using with Alfresco.
Scripts for MySQL and Oracle are available in the distributions in the upgrade directory.
From the upgrade.txt readme:
Ensure you have upgraded to Alfresco 1.2.1 before starting the 1.3.0 upgrade. Then back-up all data (database and content store) and stop the Alfresco server.
Run the appropriate upgrade script for your installation. A sample script is provided for MySQL and can be executed by running 'db_upgrade_1.2.1_to_1.3.0.sh'. Make sure your database is running before executing the script.
The script will prompt you for the MySQL password for Alfresco (originally 'alfresco') and then run the database script. The script may take some time to run: it depends on the volume of data you have.
Note: The scripts/AlfrescoSchemaMigrate-1.3-mysql.sql file has case issues that must be corrected for many environments. The following changes are what seem to be needed:
I'd also recommend that the SQL script be run via methods other than web tools such as phpMyAdmin as they aren't kidding about '...may take some time to run' and you may not see errors due to timeouts.
Make sure you have made copies of any extensions or customizations to your Alfresco installation. Typically, these are in the <shared config>/classes/alfresco/extension directory.
Deploy the 1.3.0 WAR file to your application server (e.g. Tomcat or JBoss), replacing the old 'alfresco.war' file. Then restart the Alfresco server.