GnuCash 2.7+ Breaking Change

Title: GnuCash 2.7+ Breaking Change
Author: Aaron W. Swenson <titanofold@gentoo.org>
Posted: 2018-01-14
Revision: 1
News-Item-Format: 2.0
Display-If-Installed: <app-office/gnucash-4

Along with changes to use modern libraries, GnuCash 2.7+ has changed the
schema [1] it uses for both databases and files. GnuCash will
automatically modify the file or database in place upon open.

Therefore, it is imperative that you back up any files or databases
before using GnuCash 2.7 in case you run into an issue and want or need
to revert back to 2.6.

Close any open session of GnuCash including remote sessions, then
follow the relevant backup instructions as follows:

For XML (plain files):
$ cp /path/to/file.gnucash /path/to/file.gnucash.bak

For MySQL:
$ mysqldump gnucash_db | xz > gnucash-2.6.sql.xz

For PostgreSQL:
$ pg_dump -U gnucash_user -Z 5 gnucash_db > gnucash-2.6.sql.gz

For SQLite:
$ cp /path/to/sqlite.file.gnucash /path/to/sqlite.file.gnucash.bak

[1] https://github.com/Gnucash/gnucash/releases/tag/2.7.0a