timestamp.c

postgresql8.3.4源码,开源数据库

		/* This case is ts2 < te1 OR te2 < te1 */
		if (te1IsNull)
			PG_RETURN_NULL();
		if (TIMESTAMP_LT(ts2, te1))
			PG_RETURN_BOOL(true);
		if (te2IsNull)
			PG_RETURN_NULL();

		/*
		 * If te2 is not null then we had ts2 <= te2 above, and we just found
		 * ts2 >= te1, hence te2 >= te1.
		 */
		PG_RETURN_BOOL(false);
	}
	else
	{
		/*
		 * For ts1 = ts2 the spec says te1 <> te2 OR te1 = te2, which is a
		 * rather silly way of saying "true if both are nonnull, else null".
		 */
		if (te1IsNull || te2IsNull)
			PG_RETURN_NULL();
		PG_RETURN_BOOL(true);
	}

#undef TIMESTAMP_GT
#undef TIMESTAMP_LT
}


/*----------------------------------------------------------
 *	"Arithmetic" operators on date/times.
 *---------------------------------------------------------*/

Datum
timestamp_smaller(PG_FUNCTION_ARGS)
{
	Timestamp	dt1 = PG_GETARG_TIMESTAMP(0);
	Timestamp	dt2 = PG_GETARG_TIMESTAMP(1);
	Timestamp	result;

	/* use timestamp_cmp_internal to be sure this agrees with comparisons */
	if (timestamp_cmp_internal(dt1, dt2) < 0)
		result = dt1;
	else
		result = dt2;
	PG_RETURN_TIMESTAMP(result);
}

Datum
timestamp_larger(PG_FUNCTION_ARGS)
{
	Timestamp	dt1 = PG_GETARG_TIMESTAMP(0);
	Timestamp	dt2 = PG_GETARG_TIMESTAMP(1);
	Timestamp	result;

	if (timestamp_cmp_internal(dt1, dt2) > 0)
		result = dt1;
	else
		result = dt2;
	PG_RETURN_TIMESTAMP(result);
}


Datum
timestamp_mi(PG_FUNCTION_ARGS)
{
	Timestamp	dt1 = PG_GETARG_TIMESTAMP(0);
	Timestamp	dt2 = PG_GETARG_TIMESTAMP(1);
	Interval   *result;

	result = (Interval *) palloc(sizeof(Interval));

	if (TIMESTAMP_NOT_FINITE(dt1) || TIMESTAMP_NOT_FINITE(dt2))
		ereport(ERROR,
				(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
				 errmsg("cannot subtract infinite timestamps")));

	result->time = dt1 - dt2;

	result->month = 0;
	result->day = 0;

	/*----------
	 *	This is wrong, but removing it breaks a lot of regression tests.
	 *	For example:
	 *
	 *	test=> SET timezone = 'EST5EDT';
	 *	test=> SELECT
	 *	test-> ('2005-10-30 13:22:00-05'::timestamptz -
	 *	test(>	'2005-10-29 13:22:00-04'::timestamptz);
	 *	?column?
	 *	----------------
	 *	 1 day 01:00:00
	 *	 (1 row)
	 *
	 *	so adding that to the first timestamp gets:
	 *
	 *	 test=> SELECT
	 *	 test-> ('2005-10-29 13:22:00-04'::timestamptz +
	 *	 test(> ('2005-10-30 13:22:00-05'::timestamptz -
	 *	 test(>  '2005-10-29 13:22:00-04'::timestamptz)) at time zone 'EST';
	 *		timezone
	 *	--------------------
	 *	2005-10-30 14:22:00
	 *	(1 row)
	 *----------
	 */
	result = DatumGetIntervalP(DirectFunctionCall1(interval_justify_hours,
												 IntervalPGetDatum(result)));

	PG_RETURN_INTERVAL_P(result);
}

/*
 *	interval_justify_interval()
 *
 *	Adjust interval so 'month', 'day', and 'time' portions are within
 *	customary bounds.  Specifically:
 *
 *		0 <= abs(time) < 24 hours
 *		0 <= abs(day)  < 30 days
 *
 *	Also, the sign bit on all three fields is made equal, so either
 *	all three fields are negative or all are positive.
 */
Datum
interval_justify_interval(PG_FUNCTION_ARGS)
{
	Interval   *span = PG_GETARG_INTERVAL_P(0);
	Interval   *result;

#ifdef HAVE_INT64_TIMESTAMP
	int64		wholeday;
#else
	double		wholeday;
#endif
	int32		wholemonth;

	result = (Interval *) palloc(sizeof(Interval));
	result->month = span->month;
	result->day = span->day;
	result->time = span->time;

#ifdef HAVE_INT64_TIMESTAMP
	TMODULO(result->time, wholeday, USECS_PER_DAY);
#else
	TMODULO(result->time, wholeday, (double) SECS_PER_DAY);
#endif
	result->day += wholeday;	/* could overflow... */

	wholemonth = result->day / DAYS_PER_MONTH;
	result->day -= wholemonth * DAYS_PER_MONTH;
	result->month += wholemonth;

	if (result->month > 0 &&
		(result->day < 0 || (result->day == 0 && result->time < 0)))
	{
		result->day += DAYS_PER_MONTH;
		result->month--;
	}
	else if (result->month < 0 &&
			 (result->day > 0 || (result->day == 0 && result->time > 0)))
	{
		result->day -= DAYS_PER_MONTH;
		result->month++;
	}

	if (result->day > 0 && result->time < 0)
	{
#ifdef HAVE_INT64_TIMESTAMP
		result->time += USECS_PER_DAY;
#else
		result->time += (double) SECS_PER_DAY;
#endif
		result->day--;
	}
	else if (result->day < 0 && result->time > 0)
	{
#ifdef HAVE_INT64_TIMESTAMP
		result->time -= USECS_PER_DAY;
#else
		result->time -= (double) SECS_PER_DAY;
#endif
		result->day++;
	}

	PG_RETURN_INTERVAL_P(result);
}

/*
 *	interval_justify_hours()
 *
 *	Adjust interval so 'time' contains less than a whole day, adding
 *	the excess to 'day'.  This is useful for
 *	situations (such as non-TZ) where '1 day' = '24 hours' is valid,
 *	e.g. interval subtraction and division.
 */
Datum
interval_justify_hours(PG_FUNCTION_ARGS)
{
	Interval   *span = PG_GETARG_INTERVAL_P(0);
	Interval   *result;

#ifdef HAVE_INT64_TIMESTAMP
	int64		wholeday;
#else
	double		wholeday;
#endif

	result = (Interval *) palloc(sizeof(Interval));
	result->month = span->month;
	result->day = span->day;
	result->time = span->time;

#ifdef HAVE_INT64_TIMESTAMP
	TMODULO(result->time, wholeday, USECS_PER_DAY);
#else
	TMODULO(result->time, wholeday, (double) SECS_PER_DAY);
#endif
	result->day += wholeday;	/* could overflow... */

	if (result->day > 0 && result->time < 0)
	{
#ifdef HAVE_INT64_TIMESTAMP
		result->time += USECS_PER_DAY;
#else
		result->time += (double) SECS_PER_DAY;
#endif
		result->day--;
	}
	else if (result->day < 0 && result->time > 0)
	{
#ifdef HAVE_INT64_TIMESTAMP
		result->time -= USECS_PER_DAY;
#else
		result->time -= (double) SECS_PER_DAY;
#endif
		result->day++;
	}

	PG_RETURN_INTERVAL_P(result);
}

/*
 *	interval_justify_days()
 *
 *	Adjust interval so 'day' contains less than 30 days, adding
 *	the excess to 'month'.
 */
Datum
interval_justify_days(PG_FUNCTION_ARGS)
{
	Interval   *span = PG_GETARG_INTERVAL_P(0);
	Interval   *result;
	int32		wholemonth;

	result = (Interval *) palloc(sizeof(Interval));
	result->month = span->month;
	result->day = span->day;
	result->time = span->time;

	wholemonth = result->day / DAYS_PER_MONTH;
	result->day -= wholemonth * DAYS_PER_MONTH;
	result->month += wholemonth;

	if (result->month > 0 && result->day < 0)
	{
		result->day += DAYS_PER_MONTH;
		result->month--;
	}
	else if (result->month < 0 && result->day > 0)
	{
		result->day -= DAYS_PER_MONTH;
		result->month++;
	}

	PG_RETURN_INTERVAL_P(result);
}

/* timestamp_pl_interval()
 * Add a interval to a timestamp data type.
 * Note that interval has provisions for qualitative year/month and day
 *	units, so try to do the right thing with them.
 * To add a month, increment the month, and use the same day of month.
 * Then, if the next month has fewer days, set the day of month
 *	to the last day of month.
 * To add a day, increment the mday, and use the same time of day.
 * Lastly, add in the "quantitative time".
 */
Datum
timestamp_pl_interval(PG_FUNCTION_ARGS)
{
	Timestamp	timestamp = PG_GETARG_TIMESTAMP(0);
	Interval   *span = PG_GETARG_INTERVAL_P(1);
	Timestamp	result;

	if (TIMESTAMP_NOT_FINITE(timestamp))
		result = timestamp;
	else
	{
		if (span->month != 0)
		{
			struct pg_tm tt,
					   *tm = &tt;
			fsec_t		fsec;

			if (timestamp2tm(timestamp, NULL, tm, &fsec, NULL, NULL) != 0)
				ereport(ERROR,
						(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
						 errmsg("timestamp out of range")));

			tm->tm_mon += span->month;
			if (tm->tm_mon > MONTHS_PER_YEAR)
			{
				tm->tm_year += (tm->tm_mon - 1) / MONTHS_PER_YEAR;
				tm->tm_mon = ((tm->tm_mon - 1) % MONTHS_PER_YEAR) + 1;
			}
			else if (tm->tm_mon < 1)
			{
				tm->tm_year += tm->tm_mon / MONTHS_PER_YEAR - 1;
				tm->tm_mon = tm->tm_mon % MONTHS_PER_YEAR + MONTHS_PER_YEAR;
			}

			/* adjust for end of month boundary problems... */
			if (tm->tm_mday > day_tab[isleap(tm->tm_year)][tm->tm_mon - 1])
				tm->tm_mday = (day_tab[isleap(tm->tm_year)][tm->tm_mon - 1]);

			if (tm2timestamp(tm, fsec, NULL, &timestamp) != 0)
				ereport(ERROR,
						(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
						 errmsg("timestamp out of range")));
		}

		if (span->day != 0)
		{
			struct pg_tm tt,
					   *tm = &tt;
			fsec_t		fsec;
			int			julian;

			if (timestamp2tm(timestamp, NULL, tm, &fsec, NULL, NULL) != 0)
				ereport(ERROR,
						(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
						 errmsg("timestamp out of range")));

			/* Add days by converting to and from julian */
			julian = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) + span->day;
			j2date(julian, &tm->tm_year, &tm->tm_mon, &tm->tm_mday);

			if (tm2timestamp(tm, fsec, NULL, &timestamp) != 0)
				ereport(ERROR,
						(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
						 errmsg("timestamp out of range")));
		}

		timestamp += span->time;
		result = timestamp;
	}

	PG_RETURN_TIMESTAMP(result);
}

Datum
timestamp_mi_interval(PG_FUNCTION_ARGS)
{
	Timestamp	timestamp = PG_GETARG_TIMESTAMP(0);
	Interval   *span = PG_GETARG_INTERVAL_P(1);
	Interval	tspan;

	tspan.month = -span->month;
	tspan.day = -span->day;
	tspan.time = -span->time;

	return DirectFunctionCall2(timestamp_pl_interval,
							   TimestampGetDatum(timestamp),
							   PointerGetDatum(&tspan));
}


/* timestamptz_pl_interval()
 * Add a interval to a timestamp with time zone data type.
 * Note that interval has provisions for qualitative year/month
 *	units, so try to do the right thing with them.
 * To add a month, increment the month, and use the same day of month.
 * Then, if the next month has fewer days, set the day of month
 *	to the last day of month.
 * Lastly, add in the "quantitative time".
 */
Datum
timestamptz_pl_interval(PG_FUNCTION_ARGS)
{
	TimestampTz timestamp = PG_GETARG_TIMESTAMPTZ(0);
	Interval   *span = PG_GETARG_INTERVAL_P(1);
	TimestampTz result;
	int			tz;
	char	   *tzn;

	if (TIMESTAMP_NOT_FINITE(timestamp))
		result = timestamp;
	else
	{
		if (span->month != 0)
		{
			struct pg_tm tt,
					   *tm = &tt;
			fsec_t		fsec;

			if (timestamp2tm(timestamp, &tz, tm, &fsec, &tzn, NULL) != 0)
				ereport(ERROR,
						(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
						 errmsg("timestamp out of range")));

			tm->tm_mon += span->month;
			if (tm->tm_mon > MONTHS_PER_YEAR)
			{
				tm->tm_year += (tm->tm_mon - 1) / MONTHS_PER_YEAR;
				tm->tm_mon = ((tm->tm_mon - 1) % MONTHS_PER_YEAR) + 1;
			}
			else if (tm->tm_mon < 1)
			{
				tm->tm_year += tm->tm_mon / MONTHS_PER_YEAR - 1;
				tm->tm_mon = tm->tm_mon % MONTHS_PER_YEAR + MONTHS_PER_YEAR;
			}

			/* adjust for end of month boundary problems... */
			if (tm->tm_mday > day_tab[isleap(tm->tm_year)][tm->tm_mon - 1])
				tm->tm_mday = (day_tab[isleap(tm->tm_year)][tm->tm_mon - 1]);

			tz = DetermineTimeZoneOffset(tm, session_timezone);

			if (tm2timestamp(tm, fsec, &tz, &timestamp) != 0)
				ereport(ERROR,
						(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
						 errmsg("timestamp out of range")));
		}

		if (span->day != 0)
		{
			struct pg_tm tt,
					   *tm = &tt;
			fsec_t		fsec;
			int			julian;

			if (timestamp2tm(timestamp, &tz, tm, &fsec, &tzn, NULL) != 0)
				ereport(ERROR,
						(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
						 errmsg("timestamp out of range")));

			/* Add days by converting to and from julian */
			julian = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) + span->day;
			j2date(julian, &tm->tm_year, &tm->tm_mon, &tm->tm_mday);

			tz = DetermineTimeZoneOffset(tm, session_timezone);

			if (tm2timestamp(tm, fsec, &tz, &timestamp) != 0)
				ereport(ERROR,
						(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
						 errmsg("timestamp out of range")));
		}

		timestamp += span->time;
		result = timestamp;
	}

	PG_RETURN_TIMESTAMP(result);
}

Datum
timestamptz_mi_interval(PG_FUNCTION_ARGS)
{
	TimestampTz timestamp = PG_GETARG_TIMESTAMPTZ(0);
	Interval   *span = PG_GETARG_INTERVAL_P(1);
	Interval	tspan;

	tspan.month = -span->month;
	tspan.day = -span->day;
	tspan.time = -span->time;

	return DirectFunctionCall2(timestamptz_pl_interval,
							   TimestampGetDatum(timestamp),
							   PointerGetDatum(&tspan));
}


Datum
interval_um(PG_FUNCTION_ARGS)
{
	Interval   *interval = PG_GETARG_INTERVAL_P(0);
	Interval   *result;

	result = (Interval *) palloc(sizeof(Interval));

	result->time = -interval->time;
	result->day = -interval->day;
	result->month = -interval->month;

	PG_RETURN_INTERVAL_P(result);
}


Datum
interval_smaller(PG_FUNCTION_ARGS)
{
	Interval   *interval1 = PG_GETARG_INTERVAL_P(0);
	Interval   *interval2 = PG_GETARG_INTERVAL_P(1);
	Interval   *result;

	/* use interval_cmp_internal to be sure this agrees with comparisons */
	if (interval_cmp_internal(interval1, interval2) < 0)
		result = interval1;
	else
		result = interval2;
	PG_RETURN_INTERVAL_P(result);
}

Datum
interval_larger(PG_FUNCTION_ARGS)
{
	Interval   *interval1 = PG_GETARG_INTERVAL_P(0);
	Interval   *interval2 = PG_GETARG_INTERVAL_P(1);
	Interval   *result;

	if (interval_cmp_internal(interval1, interval2) > 0)
		result = interval1;
	else
		result = interval2;
	PG_RETURN_INTERVAL_P(result);
}

Datum
interval_pl(PG_FUNCTION_ARGS)
{
	Interval   *span1 = PG_GETARG_INTERVAL_P(0);
	Interval   *span2 = PG_GETARG_INTERVAL_P(1);
	Interval   *result;

	result = (Interval *) palloc(sizeof(Interval));

	result->month = span1->month + span2->month;
	result->day = span1->day + span2->day;
	result->time = span1->time + span2->time;

	PG_RETURN_INTERVAL_P(result);
}

Datum
interval_mi(PG_FUNCTION_ARGS)
{
	Interval   *span1 = PG_GETARG_INTERVAL_P(0);
	Interval   *span2 = PG_GETARG_INTERVAL_P(1);
	Interval   *result;

	result = (Interval *) palloc(sizeof(Interval));

	result->month = span1->month - span2->month;
	result->day = span1->day - span2->day;
	result->time = span1->time - span2->ti