SUMMARY Akonadi was migrated from postgres96 to postgres 12 (following https://userbase.kde.org/Akonadi/Postgres_update), migration went OK. Afterwards it does not start with the following error: org.kde.pim.akonadiserver: "\nSql error: ERROR: column \"version\" of relation \"schemaversiontable\" already exists\n(42701) QPSQL: Unable to create query\nQuery: ALTER TABLE SchemaVersionTable ADD COLUMN version INTEGER NOT NULL DEFAULT 0" org.kde.pim.akonadiserver: Unable to initialize database. Operating System: openSUSE Leap 15.2 KDE Plasma Version: 5.18.5 KDE Frameworks Version: 5.71.0 Qt Version: 5.12.7
Looks like this was a qt issue: https://bugzilla.opensuse.org/show_bug.cgi?id=1173758 As it worked with the above patch, I close the bug