Add 'day' field to INTERVAL so 1 day interval can be distinguished from

24 hours. This is very helpful for daylight savings time:

	select '2005-05-03 00:00:00 EST'::timestamp with time zone + '24 hours';
	      ?column?
	----------------------
	2005-05-04 01:00:00-04

	select '2005-05-03 00:00:00 EST'::timestamp with time zone + '1 day';
	      ?column?
	----------------------
	2005-05-04 01:00:00-04

Michael Glaesemann

doc/src/sgml/func.sgml

 <!--
-$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.267 2005/07/18 22:34:14 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.268 2005/07/20 16:42:29 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -5144,6 +5144,22 @@ SELECT SUBSTRING('XY1234Z', 'Y*?([0-9]{1,3})');
         <entry><literal>true</literal></entry>
        </row>
 
+       <row>
+        <entry><literal><function>justify_hours</function>(<type>interval</type>)</literal></entry>
+        <entry><type>interval</type></entry>
+        <entry>Adjust interval so 24-hour time periods are represented as days</entry>
+        <entry><literal>justify_hours(interval '24 hours')</literal></entry>
+        <entry><literal>1 day</literal></entry>
+       </row>
+
+       <row>
+        <entry><literal><function>justify_days</function>(<type>interval</type>)</literal></entry>
+        <entry><type>interval</type></entry>
+        <entry>Adjust interval so 30-day time periods are represented as months</entry>
+        <entry><literal>justify_days(interval '30 days')</literal></entry>
+        <entry><literal>1 month</literal></entry>
+       </row>
+
        <row>
         <entry><literal><function>localtime</function></literal></entry>
         <entry><type>time</type></entry>

src/backend/commands/variable.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/variable.c,v 1.109 2005/06/28 05:08:55 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/variable.c,v 1.110 2005/07/20 16:42:30 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -292,6 +292,15 @@ assign_timezone(const char *value, bool doit, GucSource source)
 			pfree(interval);
 			return NULL;
 		}
+		if (interval->day != 0)
+		{
+			if (source >= PGC_S_INTERACTIVE)
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("invalid interval value for time zone: day not allowed")));
+			pfree(interval);
+			return NULL;
+		}
 		if (doit)
 		{
 			/* Here we change from SQL to Unix sign convention */
@@ -414,6 +423,7 @@ show_timezone(void)
 		Interval interval;
 
 		interval.month = 0;
+		interval.day = 0;
 #ifdef HAVE_INT64_TIMESTAMP
 		interval.time = -(CTimeZone * USECS_PER_SEC);
 #else

src/backend/utils/adt/date.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/date.c,v 1.112 2005/07/12 15:17:44 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/date.c,v 1.113 2005/07/20 16:42:30 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1423,6 +1423,7 @@ time_interval(PG_FUNCTION_ARGS)
 	result = (Interval *) palloc(sizeof(Interval));
 
 	result->time = time;
+	result->day = 0;
 	result->month = 0;
 
 	PG_RETURN_INTERVAL_P(result);
@@ -1477,8 +1478,9 @@ time_mi_time(PG_FUNCTION_ARGS)
 
 	result = (Interval *) palloc(sizeof(Interval));
 
-	result->time = (time1 - time2);
 	result->month = 0;
+	result->day = 0;
+	result->time = time1 - time2;
 
 	PG_RETURN_INTERVAL_P(result);
 }

src/backend/utils/adt/formatting.c

 /* -----------------------------------------------------------------------
  * formatting.c
  *
- * $PostgreSQL: pgsql/src/backend/utils/adt/formatting.c,v 1.90 2005/06/24 01:10:11 neilc Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/formatting.c,v 1.91 2005/07/20 16:42:30 momjian Exp $
  *
  *
  *	 Portions Copyright (c) 1999-2005, PostgreSQL Global Development Group
@@ -899,7 +899,7 @@ static char *str_tolower(char *buff);
 /* static int is_acdc(char *str, int *len); */
 static int	seq_search(char *name, char **array, int type, int max, int *len);
 static void do_to_timestamp(text *date_txt, text *fmt,
-				struct pg_tm * tm, fsec_t *fsec);
+				struct pg_tm *tm, fsec_t *fsec);
 static char *fill_str(char *str, int c, int max);
 static FormatNode *NUM_cache(int len, NUMDesc *Num, char *pars_str, bool *shouldFree);
 static char *int_to_roman(int number);
@@ -3028,7 +3028,7 @@ to_date(PG_FUNCTION_ARGS)
  */
 static void
 do_to_timestamp(text *date_txt, text *fmt,
-				struct pg_tm * tm, fsec_t *fsec)
+				struct pg_tm *tm, fsec_t *fsec)
 {
 	FormatNode *format;
 	TmFromChar	tmfc;

src/backend/utils/adt/nabstime.c

@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/nabstime.c,v 1.135 2005/07/12 16:04:56 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/nabstime.c,v 1.136 2005/07/20 16:42:30 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -829,7 +829,8 @@ interval_reltime(PG_FUNCTION_ARGS)
 	Interval   *interval = PG_GETARG_INTERVAL_P(0);
 	RelativeTime time;
 	int			year,
-				month;
+				month,
+				day;
 
 #ifdef HAVE_INT64_TIMESTAMP
 	int64		span;
@@ -837,28 +838,17 @@ interval_reltime(PG_FUNCTION_ARGS)
 	double		span;
 #endif
 
-	if (interval->month == 0)
-	{
-		year = 0;
-		month = 0;
-	}
-	else if (abs(interval->month) >=12)
-	{
-		year = (interval->month / 12);
-		month = (interval->month % 12);
-	}
-	else
-	{
-		year = 0;
-		month = interval->month;
-	}
+	year = interval->month / 12;
+	month = interval->month % 12;
+	day = interval->day;
 
 #ifdef HAVE_INT64_TIMESTAMP
-	span = ((INT64CONST(365250000) * year + INT64CONST(30000000) * month) *
-			INT64CONST(86400)) + interval->time;
+	span = ((INT64CONST(365250000) * year + INT64CONST(30000000) * month +
+			INT64CONST(1000000) * day) * INT64CONST(86400)) +
+			interval->time;
 	span /= USECS_PER_SEC;
 #else
-	span = (365.25 * year + 30.0 * month) * SECS_PER_DAY + interval->time;
+	span = (365.25 * year + 30.0 * month + day) * SECS_PER_DAY + interval->time;
 #endif
 
 	if (span < INT_MIN || span > INT_MAX)
@@ -876,7 +866,8 @@ reltime_interval(PG_FUNCTION_ARGS)
 	RelativeTime reltime = PG_GETARG_RELATIVETIME(0);
 	Interval   *result;
 	int			year,
-				month;
+				month,
+				day;
 
 	result = (Interval *) palloc(sizeof(Interval));
 
@@ -887,6 +878,7 @@ reltime_interval(PG_FUNCTION_ARGS)
 					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 			  errmsg("cannot convert reltime \"invalid\" to interval")));
 			result->time = 0;
+			result->day = 0;
 			result->month = 0;
 			break;
 
@@ -896,15 +888,19 @@ reltime_interval(PG_FUNCTION_ARGS)
 			reltime -= (year * (36525 * 864));
 			month = (reltime / (30 * SECS_PER_DAY));
 			reltime -= (month * (30 * SECS_PER_DAY));
+			day = reltime / SECS_PER_DAY;
+			reltime -= day * SECS_PER_DAY;
 
 			result->time = (reltime * USECS_PER_SEC);
 #else
 			TMODULO(reltime, year, 36525 * 864);
 			TMODULO(reltime, month, 30 * SECS_PER_DAY);
+			TMODULO(reltime, day, SECS_PER_DAY);
 
 			result->time = reltime;
 #endif
 			result->month = 12 * year + month;
+			result->day = day;
 			break;
 	}
 

src/backend/utils/adt/selfuncs.c

@@ -15,7 +15,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.184 2005/07/12 16:04:57 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.185 2005/07/20 16:42:30 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -2784,10 +2784,11 @@ convert_timevalue_to_scalar(Datum value, Oid typid)
 				 * too accurate, but plenty good enough for our purposes.
 				 */
 #ifdef HAVE_INT64_TIMESTAMP
-				return (interval->time + (interval->month * ((365.25 / 12.0) * 86400000000.0)));
+				return interval->time + interval->day * (double)USECS_PER_DAY +
+					   interval->month * ((365.25 / 12.0) * USECS_PER_DAY);
 #else
-				return interval->time +
-				interval  ->month * (365.25 / 12.0 * 24.0 * 60.0 * 60.0);
+				return interval->time + interval->day * SECS_PER_DAY +
+						interval->month * ((365.25 / 12.0) * (double)SECS_PER_DAY);
 #endif
 			}
 		case RELTIMEOID:

src/include/catalog/pg_proc.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.376 2005/07/10 21:13:59 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.377 2005/07/20 16:42:31 momjian Exp $
  *
  * NOTES
  *	  The script catalog/genbki.sh reads this file and generates .bki
@@ -1497,6 +1497,10 @@ DATA(insert OID = 1173 (  timestamptz	   PGNSP PGUID 12 f f t f i 1 1184 "702" _
 DESCR("convert abstime to timestamp with time zone");
 DATA(insert OID = 1174 (  timestamptz	   PGNSP PGUID 12 f f t f s 1 1184 "1082" _null_ _null_ _null_  date_timestamptz - _null_ ));
 DESCR("convert date to timestamp with time zone");
+DATA(insert OID = 1175 (  justify_hours	   PGNSP PGUID 12 f f t f i 1 1186 "1186" _null_ _null_ _null_  interval_justify_hours - _null_ ));
+DESCR("promote groups of 24 hours to numbers of days");
+DATA(insert OID = 1295 (  justify_days	   PGNSP PGUID 12 f f t f i 1 1186 "1186" _null_ _null_ _null_  interval_justify_days - _null_ ));
+DESCR("promote groups of 30 days to numbers of months");
 DATA(insert OID = 1176 (  timestamptz	   PGNSP PGUID 14 f f t f s 2 1184 "1082 1083" _null_ _null_ _null_	"select cast(($1 + $2) as timestamp with time zone)" - _null_ ));
 DESCR("convert date and time to timestamp with time zone");
 DATA(insert OID = 1177 (  interval		   PGNSP PGUID 12 f f t f i 1 1186 "703" _null_ _null_ _null_ reltime_interval - _null_ ));

src/include/catalog/pg_type.h

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/pg_type.h,v 1.163 2005/07/07 20:39:59 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_type.h,v 1.164 2005/07/20 16:42:32 momjian Exp $
  *
  * NOTES
  *	  the genbki.sh script reads this file and generates .bki
@@ -457,7 +457,7 @@ DATA(insert OID = 1184 ( timestamptz PGNSP PGUID	8 f b t \054 0	0 timestamptz_in
 DESCR("date and time with time zone");
 #define TIMESTAMPTZOID	1184
 DATA(insert OID = 1185 ( _timestamptz PGNSP PGUID -1 f b t \054 0	1184 array_in array_out array_recv array_send - d x f 0 -1 0 _null_ _null_ ));
-DATA(insert OID = 1186 ( interval	 PGNSP PGUID 12 f b t \054 0	0 interval_in interval_out interval_recv interval_send - d p f 0 -1 0 _null_ _null_ ));
+DATA(insert OID = 1186 ( interval	 PGNSP PGUID 16 f b t \054 0	0 interval_in interval_out interval_recv interval_send - d p f 0 -1 0 _null_ _null_ ));
 DESCR("@ <number> <units>, time interval");
 #define INTERVALOID		1186
 DATA(insert OID = 1187 ( _interval	 PGNSP PGUID	-1 f b t \054 0 1186 array_in array_out array_recv array_send - d x f 0 -1 0 _null_ _null_ ));

src/include/utils/timestamp.h

@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/utils/timestamp.h,v 1.46 2005/06/29 22:51:57 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/utils/timestamp.h,v 1.47 2005/07/20 16:42:32 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -25,9 +25,9 @@
 
 /*
  * Timestamp represents absolute time.
- * Interval represents delta time. Keep track of months (and years)
- *	separately since the elapsed time spanned is unknown until instantiated
- *	relative to an absolute time.
+ * Interval represents delta time. Keep track of months (and years), days,
+ *	and time separately since the elapsed time spanned is unknown until
+ *	instantiated relative to an absolute time.
  *
  * Note that Postgres uses "time interval" to mean a bounded interval,
  * consisting of a beginning and ending time, not a time span - thomas 97/03/20
@@ -45,12 +45,13 @@ typedef double TimestampTz;
 typedef struct
 {
 #ifdef HAVE_INT64_TIMESTAMP
-	int64		time;			/* all time units other than months and
-								 * years */
+	int64		time;			/* all time units other than days, 
+								 * months and years */
 #else
-	double		time;			/* all time units other than months and
-								 * years */
+	double		time;			/* all time units other than days,
+								 * months and years */
 #endif
+	int32		day;		    /* days, after time for alignment */
 	int32		month;			/* months and years, after time for
 								 * alignment */
 } Interval;
@@ -60,6 +61,7 @@ typedef struct
 #define MAX_INTERVAL_PRECISION 6
 
 #define SECS_PER_DAY	86400
+#define SECS_PER_HOUR   3600
 #ifdef HAVE_INT64_TIMESTAMP
 #define USECS_PER_DAY	INT64CONST(86400000000)
 #define USECS_PER_HOUR	INT64CONST(3600000000)
@@ -212,6 +214,8 @@ extern Datum interval_cmp(PG_FUNCTION_ARGS);
 extern Datum interval_hash(PG_FUNCTION_ARGS);
 extern Datum interval_smaller(PG_FUNCTION_ARGS);
 extern Datum interval_larger(PG_FUNCTION_ARGS);
+extern Datum interval_justify_hours(PG_FUNCTION_ARGS);
+extern Datum interval_justify_days(PG_FUNCTION_ARGS);
 
 extern Datum timestamp_text(PG_FUNCTION_ARGS);
 extern Datum text_timestamp(PG_FUNCTION_ARGS);
@@ -266,16 +270,16 @@ extern Datum pgsql_postmaster_start_time(PG_FUNCTION_ARGS);
 
 extern TimestampTz GetCurrentTimestamp(void);
 
-extern int	tm2timestamp(struct pg_tm * tm, fsec_t fsec, int *tzp, Timestamp *dt);
-extern int timestamp2tm(Timestamp dt, int *tzp, struct pg_tm * tm,
+extern int	tm2timestamp(struct pg_tm *tm, fsec_t fsec, int *tzp, Timestamp *dt);
+extern int timestamp2tm(Timestamp dt, int *tzp, struct pg_tm *tm,
 			 fsec_t *fsec, char **tzn, pg_tz *attimezone);
 extern void dt2time(Timestamp dt, int *hour, int *min, int *sec, fsec_t *fsec);
 
-extern int	interval2tm(Interval span, struct pg_tm * tm, fsec_t *fsec);
-extern int	tm2interval(struct pg_tm * tm, fsec_t fsec, Interval *span);
+extern int	interval2tm(Interval span, struct pg_tm *tm, fsec_t *fsec);
+extern int	tm2interval(struct pg_tm *tm, fsec_t fsec, Interval *span);
 
 extern Timestamp SetEpochTimestamp(void);
-extern void GetEpochTime(struct pg_tm * tm);
+extern void GetEpochTime(struct pg_tm *tm);
 
 extern int	timestamp_cmp_internal(Timestamp dt1, Timestamp dt2);
 

src/interfaces/ecpg/pgtypeslib/interval.c

@@ -33,7 +33,7 @@ TrimTrailingZeros(char *str)
  *	can be used to represent time spans.
  */
 static int
-DecodeTime(char *str, int fmask, int *tmask, struct tm * tm, fsec_t *fsec)
+DecodeTime(char *str, int fmask, int *tmask, struct tm *tm, fsec_t *fsec)
 {
 	char	   *cp;
 
@@ -107,7 +107,7 @@ DecodeTime(char *str, int fmask, int *tmask, struct tm * tm, fsec_t *fsec)
  *	preceding an hh:mm:ss field. - thomas 1998-04-30
  */
 int
-DecodeInterval(char **field, int *ftype, int nf, int *dtype, struct tm * tm, fsec_t *fsec)
+DecodeInterval(char **field, int *ftype, int nf, int *dtype, struct tm *tm, fsec_t *fsec)
 {
 	int			is_before = FALSE;
 
@@ -445,7 +445,7 @@ DecodeInterval(char **field, int *ftype, int nf, int *dtype, struct tm * tm, fse
  * - thomas 1998-04-30
  */
 int
-EncodeInterval(struct tm * tm, fsec_t fsec, int style, char *str)
+EncodeInterval(struct tm *tm, fsec_t fsec, int style, char *str)
 {
 	int			is_before = FALSE;
 	int			is_nonzero = FALSE;
@@ -670,7 +670,7 @@ EncodeInterval(struct tm * tm, fsec_t fsec, int style, char *str)
  * Convert a interval data type to a tm structure.
  */
 static int
-interval2tm(interval span, struct tm * tm, fsec_t *fsec)
+interval2tm(interval span, struct tm *tm, fsec_t *fsec)
 {
 #ifdef HAVE_INT64_TIMESTAMP
 	int64		time;
@@ -713,7 +713,7 @@ interval2tm(interval span, struct tm * tm, fsec_t *fsec)
 }	/* interval2tm() */
 
 static int
-tm2interval(struct tm * tm, fsec_t fsec, interval *span)
+tm2interval(struct tm *tm, fsec_t fsec, interval *span)
 {
 	span->month = tm->tm_year * 12 + tm->tm_mon;
 #ifdef HAVE_INT64_TIMESTAMP

src/test/regress/expected/interval.out

@@ -29,20 +29,20 @@ SELECT INTERVAL '-05' AS "Five hours";
 
 SELECT INTERVAL '-1 +02:03' AS "22 hours ago...";
   22 hours ago...  
------------------
- -21:57:00
+-------------------
+ -1 days +02:03:00
 (1 row)
 
 SELECT INTERVAL '-1 days +02:03' AS "22 hours ago...";
   22 hours ago...  
------------------
- -21:57:00
+-------------------
+ -1 days +02:03:00
 (1 row)
 
 SELECT INTERVAL '10 years -11 month -12 days +13:14' AS "9 years...";
             9 years...            
 ----------------------------------
- 9 years 1 mon -11 days -10:46:00
+ 9 years 1 mon -12 days +13:14:00
 (1 row)
 
 CREATE TABLE INTERVAL_TBL (f1 interval);