Automatically handle updated_at column

moddatetime() is a trigger that stores the current time into a timestamp field. This can be useful for tracking the last modification time of a particular row within a table.

To use, create a BEFORE UPDATE trigger using this function. Specify a single trigger argument: the name of the column to be modified. The column must be of type timestamp or timestamp with time zone.

create extension if not exists moddatetime schema extensions;

-- assuming the table name is "todos", and a timestamp column "updated_at"
-- this trigger will set the "updated_at" column to the current timestamp for every update
create trigger handle_updated_at before update on todos
for each row execute procedure moddatetime (updated_at);