Hi,
We've been considering a number of alternatives (like automatically unlocking by updating the record in DATABASECHANGELOGLOCK if the locker no longer exists) but none are very satisfactory.
Instead I have made a liquibase extension (PostgreSQL/Oracle) to lock safely but unlock if the session is killed.
More details here in README.md:
I wonder if this could become part of Liquibase itself?
If you want it, it is available with and Apache 2 licence (but will donate it to liquibase without licence).
This only works for Postgres and Oracle (the 2 databases I need ) but a more general solution is described here as well.
cheers,
Mark