template0 and template1 database dropped accidently

Question

I did not know that template0 and template1 database templates are required in order to create empty databases. I deleted them in order to clear up postgres. Now I'm not able to create any new database. Gives me this error :

ERROR:  template database "template1" does not exist

What can I do to get things going once again. I'll be very thankful for any help.

Answer 1

Luckily I had postgres database preserved because it was required for the postgres user to log into psql. Thus, created a template0 and template1 database :

create database template0 TEMPLATE postgres;

and same for template1. Then executed :

update pg_database set datistemplate=true  where datname='template0';

for both databases to stop myself from accidentally deleting these templates again.

Everything works fine now :)

Answer 2

On my CentOS 7 box, I was not so lucky as to still have a database to connect to. However:

su postgres -c "initdb /var/lib/pgsql/data"

(as root) created a template0 and template 1 to work with.