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Merged
ohbadiah merged 2 commits into from
Sep 10, 2026
Merged

sql: fork chrono-tz to deliver tzdata 2026c #38735

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9c79592
sql: fork chrono-tz to deliver tzdata 2026c
ohbadiah Sep 9, 2026
b0ce5e0
sql: pin Baja California DST history in timezone.slt
ohbadiah Sep 10, 2026
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9 changes: 3 additions & 6 deletions Cargo.lock
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6 changes: 6 additions & 0 deletions Cargo.toml
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Original file line number Diff line number Diff line change
Expand Up @@ -650,6 +650,12 @@ postgres-types = { git = "https://github.com/MaterializeInc/rust-postgres" }
postgres-openssl = { git = "https://github.com/MaterializeInc/rust-postgres" }
postgres_array = { git = "https://github.com/MaterializeInc/rust-postgres-array" }

# Upstream chrono-tz is unmaintained and stops at tzdata 2025b. The fork's
# `mz_changes` branch carries current IANA data only, no code changes. To bump
# tzdata, update the fork, then follow the bump ceremony documented in
# src/environmentd/tests/testdata/timezones/regenerate.sh.
chrono-tz = { git = "https://github.com/MaterializeInc/chrono-tz.git", rev = "5999cdd1b971694f834ec3467d11ef9147fc297c" }

# Waiting on https://github.com/MaterializeInc/serde-value/pull/35.
serde-value = { git = "https://github.com/MaterializeInc/serde-value.git" }

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14 changes: 7 additions & 7 deletions src/environmentd/tests/testdata/timezones/names-2026-12-15.csv
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Original file line number Diff line number Diff line change
Expand Up @@ -12,14 +12,14 @@ Africa/Blantyre,CAT,02:00:00,f
Africa/Brazzaville,WAT,01:00:00,f
Africa/Bujumbura,CAT,02:00:00,f
Africa/Cairo,EET,02:00:00,f
Africa/Casablanca,+01,01:00:00,f
Africa/Casablanca,+00,00:00:00,f
Africa/Ceuta,CET,01:00:00,f
Africa/Conakry,GMT,00:00:00,f
Africa/Dakar,GMT,00:00:00,f
Africa/Dar_es_Salaam,EAT,03:00:00,f
Africa/Djibouti,EAT,03:00:00,f
Africa/Douala,WAT,01:00:00,f
Africa/El_Aaiun,+01,01:00:00,f
Africa/El_Aaiun,+00,00:00:00,f
Africa/Freetown,GMT,00:00:00,f
Africa/Gaborone,CAT,02:00:00,f
Africa/Harare,CAT,02:00:00,f
Expand Down Expand Up @@ -107,7 +107,7 @@ America/Dawson_Creek,MST,-07:00:00,f
America/Denver,MST,-07:00:00,f
America/Detroit,EST,-05:00:00,f
America/Dominica,AST,-04:00:00,f
America/Edmonton,MST,-07:00:00,f
America/Edmonton,CST,-06:00:00,f
America/Eirunepe,-05,-05:00:00,f
America/El_Salvador,CST,-06:00:00,f
America/Ensenada,PST,-08:00:00,f
Expand Down Expand Up @@ -215,12 +215,12 @@ America/Thunder_Bay,EST,-05:00:00,f
America/Tijuana,PST,-08:00:00,f
America/Toronto,EST,-05:00:00,f
America/Tortola,AST,-04:00:00,f
America/Vancouver,PST,-08:00:00,f
America/Vancouver,MST,-07:00:00,f
America/Virgin,AST,-04:00:00,f
America/Whitehorse,MST,-07:00:00,f
America/Winnipeg,CST,-06:00:00,f
America/Yakutat,AKST,-09:00:00,f
America/Yellowknife,MST,-07:00:00,f
America/Yellowknife,CST,-06:00:00,f
Antarctica/Casey,+08,08:00:00,f
Antarctica/Davis,+07,07:00:00,f
Antarctica/DumontDUrville,+10,10:00:00,f
Expand Down Expand Up @@ -375,9 +375,9 @@ Brazil/West,-04,-04:00:00,f
Canada/Atlantic,AST,-04:00:00,f
Canada/Central,CST,-06:00:00,f
Canada/Eastern,EST,-05:00:00,f
Canada/Mountain,MST,-07:00:00,f
Canada/Mountain,CST,-06:00:00,f
Canada/Newfoundland,NST,-03:30:00,f
Canada/Pacific,PST,-08:00:00,f
Canada/Pacific,MST,-07:00:00,f
Canada/Saskatchewan,CST,-06:00:00,f
Canada/Yukon,MST,-07:00:00,f
CET,CET,01:00:00,f
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2 changes: 1 addition & 1 deletion src/environmentd/tests/testdata/timezones/regenerate.sh
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Expand Up @@ -29,7 +29,7 @@ set -euo pipefail

cd "$(dirname "$0")"

EXPECTED_TZDATA=2025b
EXPECTED_TZDATA=2026c
IMAGE=mz-timezone-snapshot

DATES=("$@")
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57 changes: 57 additions & 0 deletions test/sqllogictest/timezone.slt
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Expand Up @@ -358,6 +358,44 @@ SELECT timezone_offset('Asia/Almaty', '2026-07-15 00:00:00 UTC'), timezone_offse
(+05,05:00:00,00:00:00)
(EEST,02:00:00,01:00:00)

# Zones whose rules changed in tzdata 2025c through 2026c: Morocco moved to
# permanent +00 on 2026-09-20, Alberta and British Columbia abolished DST on
# their 2026 fall-back dates and keep the summer offset, and Moldova follows
# EU transition instants. Both Canadian zones now render a neighbouring
# region's standard-time abbreviation for their permanent offset.

statement ok
SET unsafe_new_transaction_wall_time = '2026-12-15 00:00:00 UTC';

query TTTT
SELECT * FROM pg_catalog.pg_timezone_names
WHERE name IN ('Africa/Casablanca', 'America/Edmonton', 'America/Vancouver', 'Europe/Chisinau')
ORDER BY name
----
Africa/Casablanca
+00
00:00:00
false
America/Edmonton
CST
-06:00:00
false
America/Vancouver
MST
-07:00:00
false
Europe/Chisinau
EET
02:00:00
false

query TTT
SELECT timezone_offset('Africa/Casablanca', '2026-09-21 00:00:00 UTC'), timezone_offset('America/Edmonton', '2026-11-15 00:00:00 UTC'), timezone_offset('America/Vancouver', '2026-11-15 00:00:00 UTC')
----
(+00,00:00:00,00:00:00)
(CST,-06:00:00,00:00:00)
(MST,-07:00:00,00:00:00)

# These pin historical rules: a timestamp from before a zone's rule change
# must resolve under the rules in force at that instant, not current rules.

Expand Down Expand Up @@ -385,3 +423,22 @@ query T
SELECT timezone_offset('Asia/Choibalsan', '1995-06-15 00:00:00 UTC')
----
(+09,08:00:00,01:00:00)

# Moldova has switched at the EU instant, 01:00 UTC, since 2022. Older data
# had it one hour earlier, so for one hour around each transition the two
# disagree. This asserts the current belief about the past. If a data update
# breaks it, IANA rewrote history.

query T
SELECT timezone_offset('Europe/Chisinau', '2023-03-26 00:30:00 UTC')
----
(EET,02:00:00,00:00:00)
Comment on lines +427 to +435

@martykulma martykulma Sep 10, 2026

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should add a similar test for America/Tijuana which retroactively updated DST


# Baja California observed DST in 1953 and 1961 through 1975, following
# California, where earlier data had none. This asserts the current belief
# about the past. If a data update breaks it, IANA rewrote history.

query T
SELECT timezone_offset('America/Tijuana', '1970-07-15 12:00:00 UTC')
----
(PDT,-08:00:00,01:00:00)
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