Change EXTRACT(EPOCH FROM timestamp) so that a timestamp without time zone

is assumed to be in local time, not GMT.  This improves consistency with
other operations, which all assume local timezone when it matters.  Per
bug #897.

diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index 6d63eef7a3b901e9e0b46d4da2060f11ca9a8a6b..d3390fd327442cddd2efdd68a6f803f22a364c2b 100644 (file)
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/utils/adt/timestamp.c,v 1.78 2003/02/22 05:57:45 tgl Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/utils/adt/timestamp.c,v 1.79 2003/02/27 21:36:58 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -2865,13 +2865,26 @@ timestamp_part(PG_FUNCTION_ARGS)
        switch (val)
        {
            case DTK_EPOCH:
+           {
+               int     tz;
+               TimestampTz timestamptz;
+
+               /* convert to timestamptz to produce consistent results */
+               if (timestamp2tm(timestamp, NULL, tm, &fsec, NULL) != 0)
+                   elog(ERROR, "Unable to convert TIMESTAMP to TIMESTAMP WITH TIME ZONE (tm)");
+
+               tz = DetermineLocalTimeZone(tm);
+
+               if (tm2timestamp(tm, fsec, &tz, ×tamptz) != 0)
+                   elog(ERROR, "Unable to convert TIMESTAMP to TIMESTAMP WITH TIME ZONE");
+
 #ifdef HAVE_INT64_TIMESTAMP
-               result = ((timestamp - SetEpochTimestamp()) / 1000000e0);
+               result = ((timestamptz - SetEpochTimestamp()) / 1000000e0);
 #else
-               result = timestamp - SetEpochTimestamp();
+               result = timestamptz - SetEpochTimestamp();
 #endif
                break;
-
+           }
            case DTK_DOW:
                if (timestamp2tm(timestamp, NULL, tm, &fsec, NULL) != 0)
                    elog(ERROR, "Unable to encode TIMESTAMP");