Interval->day docs and regression tests - Mailing list pgsql-patches

Please find attached diffs for documentation and simple regression
tests for the new interval->day changes. I added tests for
justify_hours() and justify_days() to interval.sql, as they take
interval input and produce interval output. If there's a more
appropriate place for them, please let me know.

I've included the diff in the email as well (below) for ease of review.

Michael Glaesemann
grzm myrealbox com

Index: doc/src/sgml/func.sgml
===================================================================
RCS file: /projects/cvsroot/pgsql/doc/src/sgml/func.sgml,v
retrieving revision 1.269
diff -c -r1.269 func.sgml
*** doc/src/sgml/func.sgml    22 Jul 2005 21:16:14 -0000    1.269
--- doc/src/sgml/func.sgml    26 Jul 2005 00:43:49 -0000
***************
*** 4903,4908 ****
--- 4903,4926 ----
      such pair.
     </para>

+   <para>
+    When adding an <type>interval</type> value to (or subtracting an
+    <type>interval</type> value from) a <type>timestamp with time
zone</type>
+    value, the days component advances (or decrements) the date of the
+    <type>timestamp with time zone<type> by the indicated number of
days.
+    Across daylight saving time changes (with the session tiem zone
set to a
+    time zone that recognizes DST), this means <literal>interval '1
day'</literal>
+    does not necessarily equal <literal>interval '24 hours'</literal>.
+    For example, with the session time zone set to <literal>CST7CDT</
literal>
+    <literal>timestamp with time zone '2005-04-02 12:00-07' +
interval '1 day' </literal>
+    will produce <literal>timestamp with time zone '2005-04-03
12:00-06'</literal>,
+    while adding <literal>interval '24 hours'</literal> to the same
initial
+    <type>timestamp with time zone</type> produces
+    <literal>timestamp with time zone '2005-04-03 13:00-06'</
literal>, as there is
+    a change in daylight saving time at <literal>2005-04-03 02:00</
literal> in time zone
+    <literal>CST7CDT</literal>.
+   </para>
+
       <table id="operators-datetime-table">
        <title>Date/Time Operators</title>

Index: src/test/regress/expected/horology.out
===================================================================
RCS file: /projects/cvsroot/pgsql/src/test/regress/expected/
horology.out,v
retrieving revision 1.56
diff -c -r1.56 horology.out
*** src/test/regress/expected/horology.out    27 May 2005 21:31:23
-0000    1.56
--- src/test/regress/expected/horology.out    26 Jul 2005 00:43:49 -0000
***************
*** 598,603 ****
--- 598,630 ----
    t
   (1 row)

+ -- timestamp with time zone, interval arithmetic around DST change
+ SET TIME ZONE 'CST7CDT';
+ SELECT timestamp with time zone '2005-04-02 12:00-07' + interval '1
day' as "Apr 3, 12:00";
+          Apr 3, 12:00
+ ------------------------------
+  Sun Apr 03 12:00:00 2005 CDT
+ (1 row)
+
+ SELECT timestamp with time zone '2005-04-02 12:00-07' + interval
'24 hours' as "Apr 3, 13:00";
+          Apr 3, 13:00
+ ------------------------------
+  Sun Apr 03 13:00:00 2005 CDT
+ (1 row)
+
+ SELECT timestamp with time zone '2005-04-03 12:00-06' - interval '1
day' as "Apr 2, 12:00";
+          Apr 2, 12:00
+ ------------------------------
+  Sat Apr 02 12:00:00 2005 CST
+ (1 row)
+
+ SELECT timestamp with time zone '2005-04-03 12:00-06' - interval
'24 hours' as "Apr 2, 11:00";
+          Apr 2, 11:00
+ ------------------------------
+  Sat Apr 02 11:00:00 2005 CST
+ (1 row)
+
+ RESET TIME ZONE;
   SELECT timestamptz(date '1994-01-01', time '11:00') AS
"Jan_01_1994_10am";
          Jan_01_1994_10am
   ------------------------------
Index: src/test/regress/expected/interval.out
===================================================================
RCS file: /projects/cvsroot/pgsql/src/test/regress/expected/
interval.out,v
retrieving revision 1.12
diff -c -r1.12 interval.out
*** src/test/regress/expected/interval.out    20 Jul 2005 16:42:32
-0000    1.12
--- src/test/regress/expected/interval.out    26 Jul 2005 00:43:49 -0000
***************
*** 228,230 ****
--- 228,243 ----
    @ 4541 years 4 mons 4 days 17 mins 31 secs
   (1 row)

+ -- test justify_hours() and justify_days()
+ SELECT justify_hours(interval '6 months 3 days 52 hours 3 minutes 2
seconds') as "6 mons 5 days 4 hours 3 mins 2 seconds";
+  6 mons 5 days 4 hours 3 mins 2 seconds
+ ----------------------------------------
+  @ 6 mons 5 days 4 hours 3 mins 2 secs
+ (1 row)
+
+ SELECT justify_days(interval '6 months 36 days 5 hours 4 minutes 3
seconds') as "7 mons 6 days 5 hours 4 mins 3 seconds";
+  7 mons 6 days 5 hours 4 mins 3 seconds
+ ----------------------------------------
+  @ 7 mons 6 days 5 hours 4 mins 3 secs
+ (1 row)
+
Index: src/test/regress/sql/horology.sql
===================================================================
RCS file: /projects/cvsroot/pgsql/src/test/regress/sql/horology.sql,v
retrieving revision 1.30
diff -c -r1.30 horology.sql
*** src/test/regress/sql/horology.sql    7 Apr 2005 01:51:41 -0000
1.30
--- src/test/regress/sql/horology.sql    26 Jul 2005 00:43:49 -0000
***************
*** 114,119 ****
--- 114,128 ----
   SELECT (timestamp with time zone 'tomorrow' = (timestamp with time
zone 'yesterday' + interval '2 days')) as "True";
   SELECT (timestamp with time zone 'tomorrow' > 'now') as "True";

+ -- timestamp with time zone, interval arithmetic around DST change
+ SET TIME ZONE 'CST7CDT';
+ SELECT timestamp with time zone '2005-04-02 12:00-07' + interval '1
day' as "Apr 3, 12:00";
+ SELECT timestamp with time zone '2005-04-02 12:00-07' + interval
'24 hours' as "Apr 3, 13:00";
+ SELECT timestamp with time zone '2005-04-03 12:00-06' - interval '1
day' as "Apr 2, 12:00";
+ SELECT timestamp with time zone '2005-04-03 12:00-06' - interval
'24 hours' as "Apr 2, 11:00";
+ RESET TIME ZONE;
+
+
   SELECT timestamptz(date '1994-01-01', time '11:00') AS
"Jan_01_1994_10am";
   SELECT timestamptz(date '1994-01-01', time '10:00') AS
"Jan_01_1994_9am";
   SELECT timestamptz(date '1994-01-01', time with time zone
'11:00-8') AS "Jan_01_1994_11am";
Index: src/test/regress/sql/interval.sql
===================================================================
RCS file: /projects/cvsroot/pgsql/src/test/regress/sql/interval.sql,v
retrieving revision 1.7
diff -c -r1.7 interval.sql
*** src/test/regress/sql/interval.sql    26 May 2005 02:04:14
-0000    1.7
--- src/test/regress/sql/interval.sql    26 Jul 2005 00:43:49 -0000
***************
*** 69,71 ****
--- 69,78 ----

   -- test long interval input
   select '4 millenniums 5 centuries 4 decades 1 year 4 months 4 days
17 minutes 31 seconds'::interval;
+
+
+ -- test justify_hours() and justify_days()
+
+ SELECT justify_hours(interval '6 months 3 days 52 hours 3 minutes 2
seconds') as "6 mons 5 days 4 hours 3 mins 2 seconds";
+ SELECT justify_days(interval '6 months 36 days 5 hours 4 minutes 3
seconds') as "7 mons 6 days 5 hours 4 mins 3 seconds";
+