Dev -> 4.0.6. Clean upgrade from 4.0.5-5.

[usit-rt.git] / docs / UPGRADING.mysql

If you did not start by reading the README file, please start there;
these steps do not list the full upgrading process, merely a part which
is sometimes necessary.

This file applies if either:

 1) You are upgrading RT from a version prior to 3.8.0, on any version
    of MySQL
............. OR .............
 2) You are migrating from MySQL 4.0 to MySQL 4.1 or above

If neither of the above cases apply, your should upgrade as per the
instructions in the README.

These changes are necessary because MySQL 4.1 and greater changed some
aspects of character set handling that may result in RT failures; this
will manifest as multiple login requests, corrupted binary attachments,
and corrupted image custom fields, among others.  In order to resolve
this issue, the upgrade process will need to modify the schema.

 1) If you are moving the database and/or upgrading MySQL
   1a) Dump the database; with MySQL 4.1 and greater be sure to pass
       the mysqldump command the --default-character-set=binary option.
       This is necessary because the data was originally encoded in
       Latin1.

   1b) Configure the new MySQL to use Latin1 as the default character
       set everywhere, not UTF-8.  This is necessary so the import in
       the next step assumes the data is Latin1.

   1c) Import the dump made in step 1a into the new MySQL server, using
       the --default-character-set=binary option on restore.  This will
       ensure that the data is imported as bytes, which will be
       interpreted as Latin1 thanks to step 1b above.

   1d) Test that your RT works as expected on this new database.

 2) Backup RT's database using --default-character-set=binary
    Furthermore, test that you can restore from this backup.

 3) Follow instructions in the README file to step 6b.

 4) Apply changes described in the README's step 6b, but only up to
    version 3.7.87.

 5) Apply the RT 3.8 schema upgrades. Included in RT is the script
    etc/upgrade/upgrade-mysql-schema.pl that will generate the
    appropriate SQL queries:

        perl etc/upgrade/upgrade-mysql-schema.pl db user pass > queries.sql

    If your mysql database is on a remote host, you can run the script
    like this instead:

        perl etc/upgrade/upgrade-mysql-schema.pl db:host user pass > queries.sql

 6) Check the sanity of the SQL queries in the queries.sql file
    yourself, or consult with your DBA.

 7) Apply the queries. Note that this step can take a while; it may also
    require additional space on your hard drive comparable with size of
    your tables.

        mysql -u root -p rt3 < queries.sql

    NOTE that 'rt3' is the default name of the RT database, change it in
    the command above if your database is named differently.

    This step should not produce any errors or warnings. If you see any,
    restore your database from the backup you made at step 1, and send a
    report to the rt-users@lists.bestpractical.com mailing list.

 8) Re-run the `make upgrade-database` command from step 6b of the
    README, applying the rest of the upgrades, starting with 3.7.87, and
    follow the README's remaining steps.

 9) Test everything. The most important parts you have to test:
     * binary attachments, like docs, PDFs, and images
     * binary custom fields
     * everything that may contain characters other than ASCII

10) If you were upgrading from MySQL 4.0, you may now, if you wish,
    reconfigure your newer MySQL instance to use UTF-8 as the default
    character set, as step 7 above adjusted the character sets on all
    existing tables to contain UTF-8 encoded data, rather than Latin1.