how to set datcollate to en_US.UTF-8 in postgres code example

Example 1: how to set datcollate to en_US.UTF-8 in postgres

update pg_database set datcollate='en_US.UTF-8', datctype='en_US.UTF-8'
where datname='datamart_mock';

Example 2: how to set datcollate to en_US.UTF-8 in postgres

update pg_database set datcollate='en_US.UTF-8', datctype='en_US.UTF-8'
where datname='datamart_mock';