postgres.git / summary / log / commit / refs
commit 171c377a0abe12d1418540dc154feccd9355995e
Author: Bruce Momjian <bruce@momjian.us>
Date: Thu Nov 06 07:33:05 2014 +0000
C comment: mention why the Gregorian calendar is used pre-1582
src/include/utils/datetime.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/src/include/utils/datetime.h b/src/include/utils/datetime.h
index 9b53ee38ccf..548758a1493 100644
--- a/src/include/utils/datetime.h
+++ b/src/include/utils/datetime.h
@@ -271,6 +271,11 @@ extern const char *const months[]; /* months (3-char abbreviations) */
extern const char *const days[]; /* days (full names) */
extern const int day_tab[2][13];
+/*
+ * These are the rules for the Gregorian calendar, which was adopted in 1582.
+ * However, we use this calculation for all prior years as well because the
+ * SQL standard specifies use of the Gregorian calendar.
+ */
#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
[parent: 525a489915ca]