ALTER COLLATION name RENAME TO new_name ALTER COLLATION name OWNER TO new_owner ALTER COLLATION name SET SCHEMA new_schema
ALTER COLLATION changes the definition of a collation.
You must own the collation to use ALTER COLLATION. To alter the owner, you must also be a direct or indirect member of the new owning role, and that role must have CREATE privilege on the collation's schema. (These restrictions enforce that altering the owner doesn't do anything you couldn't do by dropping and recreating the collation. However, a superuser can alter ownership of any collation anyway.)
The name (optionally schema-qualified) of an existing collation.
The new name of the collation.
The new owner of the collation.
The new schema for the collation.
To rename the collation de_DE to german:
ALTER COLLATION "de_DE" RENAME TO german;
To change the owner of the collation en_US to joe:
ALTER COLLATION "en_US" OWNER TO joe;