Can't Add Database Missing Indexes or convert to bigint

Hi I am gettng the standard missing index warning about missing Indexes on my openSUSE hosted NC 18.0.6 install.

To fix it I have run:
sudo -u wwwrun php occ db:add-missing-indices

But I get the following error message:
Command “db:add-missing-indices” is not defined.

Similarly I am told some Columns are needing to be converted to BigInt and I should run:
sudo -u wwwrun php occ db:convert-filecache-bigint

Which gives a similar error. Any ideas?