This is a follow up on a discussion I had with eean on Freenode IRC #maria. The issue is how to upgrade libmysqd from MySQL version 5.1 to version 5.5 (or more generally any major version upgrade), in particular as relates to Amarok's use of libmysqld. The procedure for upgrading a normal MySQL server is to run the mysql_upgrade command. However, this requires a running mysqld server, so it is not appropriate for libmysqld, or at least very inconvenient. We discussed this briefly at our MariaDB meeting in Lisbon, and here is what we came up with: One idea is to also build mysql_upgrade_embedded; this would be a variant of mysql_upgrade linked with libmysqld, so it does not depend on the mysqld server. Similarly, we would need mysqlcheck_embedded (mysqlcheck is called from mysql_upgrade). These two binaries could be included in the libmysqld package (they are small). The upgrade procedure for amarok would then be to stop amarok linked with 5.1, then run mysql_upgrade_embedded (from 5.5) against the amarok libmysqld data directory, then start amarok linked with 5.5. Does that sound useful? The other idea that came up was to add this as extra calls in the library. So that the amarok application could just call some mysql_upgrade() function instead of having to run an external upgrade binary. Would this be more useful for amarok? Either way, we then need to think on how to implement this change. We could offer to implement this (either solution I think) in MariaDB (a version of MariaDB that includes MySQL 5.5 is in the works). This would allow to use the above to upgrade Amarok to using MariaDB 5.5. Would this work? (I think it would even work to keep Amarok using MySQL 5.5 libmysqld, but using MariaDB 5.5 mysql_upgrade_embedded, though that is kind of a strange solution. Or we could provide the patch for MariaDB and you could patch libmysqld similarly to provide the same functionality in relevant distros.) Does this sound like a feasible way forward? One question about how Amarok uses libmysqld, which will help understand what is needed to solve the upgrade issue: Does Amarok use libmysqld built with the --with-embedded-privilege-control option, or use stored procedures, or other things that require the `mysql' database schema to be available in MySQL? If this does not make sense, the answer is probably "no" :-) The background: When a normal standalone mysql database server is installed, it is necessary to create the `mysql' database schema using mysql_create_db. This database schema contains such things as user accounts and passwords, stored procedure code, etc. Normally, libmysqld does not do any access control on accounts, and it is possible to use it without running mysql_install_db. In fact it's a bit hard to run mysql_install_db, as it has the same issue as mysql_upgrade. So I assume that Amarok does not do this and just does not use account privileges or stored procedures/functions, but just wanted to check? This affects how much mysql_upgrade_embedded has to do, as part of the upgrade is to add any missing columns in tables in the `mysql' database schema. - Kristian.