inputs/.TNRS/schema.sql: tnrs.Time_submitted: set default to now() (the timestamp of the start of the current transaction, http://www.postgresql.org/docs/9.1/static/functions-datetime.html) so that it would automatically be populated when rows are added. note that because the start of the current transaction instead of the exact time at insertion is used, all rows inserted in the same transaction (e.g. as part of the same batch) will have the same value for this, linking them together.