postgre> update pg_database set datallowconn=TRUE where datname='template0';
UPDATE 1
postgres> \c template0
You are now connected to database "template0".
template0> update pg_database set datistemplate=FALSE where datname='template1';
UPDATE 1
template0> drop database template1;
DROP DATABASE
template0> create database template1 with template=template0 encoding='UTF8' lc_ctype='en_US.UTF-8' lc_collate='en_US.UTF-8';
CREATE DATABASE
template0> update pg_database set datistemplate=TRUE where datname='template1';
UPDATE 1
template0> \c template1
You are now connected to database "template1".
template1> update pg_database set datallowconn=FALSE where datname='template0';
UPDATE 1