Date Functions

function current_date() returns date
function current_date(string) returns date

function date(bigint, bigint, bigint) returns date
function date(timestamp) returns date
function date(timestamp, string) returns date
function date(datetime) returns date

function date_add $1($1, interval) returns $1
	where $1 in (date, datetime, timestamp)

function date_diff $1($1, $1, date_part string) returns bigint
	where date_part in (day, week, week(monday), week(tuesday), week(wednesday), week(thursday), week(friday), week(saturday), week(sunday), isoweek, month, quarter, year, isoyear)
	where $1 in (date, datetime, timestamp)

function date_from_unix_date(bigint) returns date

function date_trunc $1($1, date_part string) returns $1
	where date_part in (day, week, week(monday), week(tuesday), week(wednesday), week(thursday), week(friday), week(saturday), week(sunday), isoweek, month, quarter, year, isoyear)
	where $1 in (date, datetime, timestamp)

function format_date $1(string, $1) returns string
	where $1 in (date, datetime, timestamp)

function last_day $1($1) returns date
	where $1 in (date, datetime)
function last_day $1($1, date_part string) returns date
	where date_part in (week, week(monday), week(tuesday), week(wednesday), week(thursday), week(friday), week(saturday), week(sunday), isoweek, month, quarter, year, isoyear)
	where $1 in (date, datetime)

function parse_date(string, string) returns date

function unix_date(date) returns bigint