Skip to content

Commit

Permalink
Handle DST changes in gapfill
Browse files Browse the repository at this point in the history
This change makes gapfill calculate timezone offsets like
we do in time_bucket when there is a supplied timezone.
Without this, timezones would not align and we get timestamp
mismatches which cause double entries for a single bucket.
  • Loading branch information
antekresic committed Jan 9, 2024
1 parent 58859cb commit 4dc29cf
Show file tree
Hide file tree
Showing 7 changed files with 105 additions and 16 deletions.
2 changes: 2 additions & 0 deletions .unreleased/fix_6507
Original file line number Diff line number Diff line change
@@ -0,0 +1,2 @@
Fixes: #6344 time_bucket_gapfill with timezones doesn't handle daylight savings
Thanks: @JerkoNikolic Thanks for reporting the issue with gapfill and DST
30 changes: 26 additions & 4 deletions tsl/src/nodes/gapfill/gapfill_exec.c
Original file line number Diff line number Diff line change
Expand Up @@ -656,10 +656,32 @@ gapfill_advance_timestamp(GapFillState *state)
* To be consistent with time_bucket we do UTC bucketing unless
* a different timezone got explicity passed to the function.
*/
next = DirectFunctionCall2(state->have_timezone ? timestamptz_pl_interval :
timestamp_pl_interval,
TimestampTzGetDatum(state->gapfill_start),
IntervalPGetDatum(state->next_offset));
if (state->have_timezone)
{
bool isnull;
/* TODO: optimize by constifying and caching the datum if possible */
Datum tzname = gapfill_exec_expr(state, get_timezone_arg(state), &isnull);
Assert(!isnull);

/* Convert to local timestamp */
next = DirectFunctionCall2(timestamptz_zone,
tzname,
TimestampTzGetDatum(state->gapfill_start));

/* Add interval */
next = DirectFunctionCall2(timestamp_pl_interval,
next,
IntervalPGetDatum(state->next_offset));

/* Convert back to specified timezone */
next = DirectFunctionCall2(timestamp_zone, tzname, next);
}
else
{
next = DirectFunctionCall2(timestamp_pl_interval,
TimestampTzGetDatum(state->gapfill_start),
IntervalPGetDatum(state->next_offset));
}
state->next_timestamp = DatumGetTimestampTz(next);
break;
default:
Expand Down
21 changes: 18 additions & 3 deletions tsl/test/shared/expected/gapfill-13.out
Original file line number Diff line number Diff line change
Expand Up @@ -3315,9 +3315,9 @@ SELECT time_bucket_gapfill('2 month'::interval, ts, 'UTC', '2000-01-01','2001-01
time_bucket_gapfill
Fri Dec 31 16:00:00 1999 PST
Tue Feb 29 16:00:00 2000 PST
Sun Apr 30 16:00:00 2000 PDT
Fri Jun 30 16:00:00 2000 PDT
Thu Aug 31 16:00:00 2000 PDT
Sun Apr 30 17:00:00 2000 PDT
Fri Jun 30 17:00:00 2000 PDT
Thu Aug 31 17:00:00 2000 PDT
Tue Oct 31 16:00:00 2000 PST
Sun Dec 31 16:00:00 2000 PST
(7 rows)
Expand Down Expand Up @@ -3391,6 +3391,21 @@ GROUP BY 1;
Fri Jun 30 15:00:00 2023 PDT |
(7 rows)

-- Test gapfill respects DST changes when generating timestamps (#6344)
SELECT time_bucket_gapfill('1 month', time, 'awst','2023-01-01', '2023-07-01' ) AS month, sum(value) AS sum
FROM month_timezone
GROUP BY 1;
month | sum
------------------------------+-------
Sat Dec 31 08:00:00 2022 PST |
Tue Jan 31 08:00:00 2023 PST |
Tue Feb 28 08:00:00 2023 PST | 3.123
Fri Mar 31 09:00:00 2023 PDT | 4.123
Sun Apr 30 09:00:00 2023 PDT | 5.123
Wed May 31 09:00:00 2023 PDT |
Fri Jun 30 09:00:00 2023 PDT |
(7 rows)

DROP TABLE month_timezone;
-- Test gapfill with additional group pathkeys added for optimization (#6396)
CREATE TABLE stocks_real_time (
Expand Down
21 changes: 18 additions & 3 deletions tsl/test/shared/expected/gapfill-14.out
Original file line number Diff line number Diff line change
Expand Up @@ -3315,9 +3315,9 @@ SELECT time_bucket_gapfill('2 month'::interval, ts, 'UTC', '2000-01-01','2001-01
time_bucket_gapfill
Fri Dec 31 16:00:00 1999 PST
Tue Feb 29 16:00:00 2000 PST
Sun Apr 30 16:00:00 2000 PDT
Fri Jun 30 16:00:00 2000 PDT
Thu Aug 31 16:00:00 2000 PDT
Sun Apr 30 17:00:00 2000 PDT
Fri Jun 30 17:00:00 2000 PDT
Thu Aug 31 17:00:00 2000 PDT
Tue Oct 31 16:00:00 2000 PST
Sun Dec 31 16:00:00 2000 PST
(7 rows)
Expand Down Expand Up @@ -3391,6 +3391,21 @@ GROUP BY 1;
Fri Jun 30 15:00:00 2023 PDT |
(7 rows)

-- Test gapfill respects DST changes when generating timestamps (#6344)
SELECT time_bucket_gapfill('1 month', time, 'awst','2023-01-01', '2023-07-01' ) AS month, sum(value) AS sum
FROM month_timezone
GROUP BY 1;
month | sum
------------------------------+-------
Sat Dec 31 08:00:00 2022 PST |
Tue Jan 31 08:00:00 2023 PST |
Tue Feb 28 08:00:00 2023 PST | 3.123
Fri Mar 31 09:00:00 2023 PDT | 4.123
Sun Apr 30 09:00:00 2023 PDT | 5.123
Wed May 31 09:00:00 2023 PDT |
Fri Jun 30 09:00:00 2023 PDT |
(7 rows)

DROP TABLE month_timezone;
-- Test gapfill with additional group pathkeys added for optimization (#6396)
CREATE TABLE stocks_real_time (
Expand Down
21 changes: 18 additions & 3 deletions tsl/test/shared/expected/gapfill-15.out
Original file line number Diff line number Diff line change
Expand Up @@ -3315,9 +3315,9 @@ SELECT time_bucket_gapfill('2 month'::interval, ts, 'UTC', '2000-01-01','2001-01
time_bucket_gapfill
Fri Dec 31 16:00:00 1999 PST
Tue Feb 29 16:00:00 2000 PST
Sun Apr 30 16:00:00 2000 PDT
Fri Jun 30 16:00:00 2000 PDT
Thu Aug 31 16:00:00 2000 PDT
Sun Apr 30 17:00:00 2000 PDT
Fri Jun 30 17:00:00 2000 PDT
Thu Aug 31 17:00:00 2000 PDT
Tue Oct 31 16:00:00 2000 PST
Sun Dec 31 16:00:00 2000 PST
(7 rows)
Expand Down Expand Up @@ -3391,6 +3391,21 @@ GROUP BY 1;
Fri Jun 30 15:00:00 2023 PDT |
(7 rows)

-- Test gapfill respects DST changes when generating timestamps (#6344)
SELECT time_bucket_gapfill('1 month', time, 'awst','2023-01-01', '2023-07-01' ) AS month, sum(value) AS sum
FROM month_timezone
GROUP BY 1;
month | sum
------------------------------+-------
Sat Dec 31 08:00:00 2022 PST |
Tue Jan 31 08:00:00 2023 PST |
Tue Feb 28 08:00:00 2023 PST | 3.123
Fri Mar 31 09:00:00 2023 PDT | 4.123
Sun Apr 30 09:00:00 2023 PDT | 5.123
Wed May 31 09:00:00 2023 PDT |
Fri Jun 30 09:00:00 2023 PDT |
(7 rows)

DROP TABLE month_timezone;
-- Test gapfill with additional group pathkeys added for optimization (#6396)
CREATE TABLE stocks_real_time (
Expand Down
21 changes: 18 additions & 3 deletions tsl/test/shared/expected/gapfill-16.out
Original file line number Diff line number Diff line change
Expand Up @@ -3317,9 +3317,9 @@ SELECT time_bucket_gapfill('2 month'::interval, ts, 'UTC', '2000-01-01','2001-01
time_bucket_gapfill
Fri Dec 31 16:00:00 1999 PST
Tue Feb 29 16:00:00 2000 PST
Sun Apr 30 16:00:00 2000 PDT
Fri Jun 30 16:00:00 2000 PDT
Thu Aug 31 16:00:00 2000 PDT
Sun Apr 30 17:00:00 2000 PDT
Fri Jun 30 17:00:00 2000 PDT
Thu Aug 31 17:00:00 2000 PDT
Tue Oct 31 16:00:00 2000 PST
Sun Dec 31 16:00:00 2000 PST
(7 rows)
Expand Down Expand Up @@ -3393,6 +3393,21 @@ GROUP BY 1;
Fri Jun 30 15:00:00 2023 PDT |
(7 rows)

-- Test gapfill respects DST changes when generating timestamps (#6344)
SELECT time_bucket_gapfill('1 month', time, 'awst','2023-01-01', '2023-07-01' ) AS month, sum(value) AS sum
FROM month_timezone
GROUP BY 1;
month | sum
------------------------------+-------
Sat Dec 31 08:00:00 2022 PST |
Tue Jan 31 08:00:00 2023 PST |
Tue Feb 28 08:00:00 2023 PST | 3.123
Fri Mar 31 09:00:00 2023 PDT | 4.123
Sun Apr 30 09:00:00 2023 PDT | 5.123
Wed May 31 09:00:00 2023 PDT |
Fri Jun 30 09:00:00 2023 PDT |
(7 rows)

DROP TABLE month_timezone;
-- Test gapfill with additional group pathkeys added for optimization (#6396)
CREATE TABLE stocks_real_time (
Expand Down
5 changes: 5 additions & 0 deletions tsl/test/shared/sql/gapfill.sql.in
Original file line number Diff line number Diff line change
Expand Up @@ -1536,6 +1536,11 @@ FROM
month_timezone
GROUP BY 1;

-- Test gapfill respects DST changes when generating timestamps (#6344)
SELECT time_bucket_gapfill('1 month', time, 'awst','2023-01-01', '2023-07-01' ) AS month, sum(value) AS sum
FROM month_timezone
GROUP BY 1;

DROP TABLE month_timezone;

-- Test gapfill with additional group pathkeys added for optimization (#6396)
Expand Down

0 comments on commit 4dc29cf

Please sign in to comment.