Hi, Alexander, please add tests with fractional seconds. remember, that in UTC the max timestamp(2) is 2038-01-19 03:14:07.99 and max timestamp(6) is 2038-01-19 03:14:07.999999 On Mar 08, Alexander Barkov wrote:

revision-id: 8c1ad2a9fe9 (mariadb-10.11.1-48-g8c1ad2a9fe9) parent(s): ce4a289f1c3 author: Alexander Barkov committer: Alexander Barkov timestamp: 2023-02-13 17:25:18 +0400 message:

MDEV-30633 DATETIME to TIMESTAMP conversion to return maximum timestamp on overflow

a bit more verbose description would be nice

diff --git a/mysql-test/main/events_bugs.result b/mysql-test/main/events_bugs.result --- a/mysql-test/main/events_bugs.result +++ b/mysql-test/main/events_bugs.result @@ -35,12 +35,34 @@ SET NAMES latin1; set @a=3; CREATE PROCEDURE p_16 () CREATE EVENT e_16 ON SCHEDULE EVERY @a SECOND DO SET @a=5; ERROR HY000: Recursion of EVENT DDL statements is forbidden when body is present +SET time_zone='+00:00'; +SET timestamp=UNIX_TIMESTAMP('2023-02-13 00:00:00'); create event e_55 on schedule at 99990101000000 do drop table t; -ERROR HY000: Incorrect AT value: '99990101000000'

Hmm, why did you not keep it an error?

+Warnings: +Warning 1292 Truncated incorrect timestamp value: '9999-01-01 00:00:00' +Warning 1105 Event scheduler is switched off, use SET GLOBAL event_scheduler=ON to enable it. diff --git a/mysql-test/main/func_time.result b/mysql-test/main/func_time.result --- a/mysql-test/main/func_time.result +++ b/mysql-test/main/func_time.result @@ -599,19 +599,25 @@ Warnings: Warning 1292 Truncated incorrect unixtime value: '2147483648' select unix_timestamp('2039-01-20 01:00:00'); unix_timestamp('2039-01-20 01:00:00') -NULL +2147483647 +Warnings: +Warning 1292 Truncated incorrect timestamp value: '2039-01-20 01:00:00'

it's consistent with MariaDB [test]> select cast(1e30 as int); +---------------------+ | cast(1e30 as int) | +---------------------+ | 9223372036854775807 | +---------------------+ 1 row in set, 1 warning (0.000 sec) Note (Code 1916): Got overflow when converting '1e30' to SIGNED BIGINT. Value truncated good. Except that it's Note vs Warning. Want to unify this somehow?

select unix_timestamp('1968-01-20 01:00:00'); unix_timestamp('1968-01-20 01:00:00') NULL

isn't it strange? That overflow is capped to max value, while underflow is NULL?

diff --git a/mysql-test/main/select.result b/mysql-test/main/select.result --- a/mysql-test/main/select.result +++ b/mysql-test/main/select.result @@ -3766,11 +3766,15 @@ AND t1.ts BETWEEN "2006-01-01" AND "2006-12-31"; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t2 const PRIMARY PRIMARY 4 const 1 1 SIMPLE t1 range ts ts 4 NULL 2 Using index condition; Using where +Warnings: +Warning 1292 Truncated incorrect timestamp value: '2999-12-31 00:00:00'

Looks questionable. The query compares timestamp with a datetime. I think in this case timestamp should be casted to a datetime (so, no warning), not vice versa.

SELECT * FROM t1 LEFT JOIN t2 ON (t1.a=t2.a) WHERE t1.a=30 AND t1.ts BETWEEN t2.dt1 AND t2.dt2 AND t1.ts BETWEEN "2006-01-01" AND "2006-12-31"; a ts a dt1 dt2 30 2006-01-03 23:00:00 30 2006-01-01 00:00:00 2999-12-31 00:00:00 +Warnings: +Warning 1292 Truncated incorrect timestamp value: '2999-12-31 00:00:00' DROP TABLE t1,t2; create table t1 (a bigint unsigned); insert into t1 values diff --git a/sql/item_timefunc.cc b/sql/item_timefunc.cc --- a/sql/item_timefunc.cc +++ b/sql/item_timefunc.cc @@ -2793,11 +2793,17 @@ bool Item_func_convert_tz::get_date(THD *thd, MYSQL_TIME *ltime, return true;

{ - uint not_used; - my_time_tmp= from_tz->TIME_to_gmt_sec(ltime, ¬_used); + uint error_code; + my_time_tmp= from_tz->TIME_to_gmt_sec(ltime, &error_code); ulong sec_part= ltime->second_part; - /* my_time_tmp is guaranteed to be in the allowed range */ - if (my_time_tmp) + /* + my_time_tmp is guaranteed to be in the allowed range. + Don't perform the conversion in case the source DATETIME was above + TIMESTAMP_MAX_VALUE (and was truncated to TIMESTAMP_MAX_VALUE).

why not?

+ */ + if (my_time_tmp && + (my_time_tmp != TIMESTAMP_MAX_VALUE || + error_code != ER_WARN_DATA_OUT_OF_RANGE))

why `my_time_tmp != TIMESTAMP_MAX_VALUE` ? shouldn't error_code check be sufficient?

to_tz->gmt_sec_to_TIME(ltime, my_time_tmp); /* we rely on the fact that no timezone conversion can change sec_part */ ltime->second_part= sec_part;

Regards, Sergei VP of MariaDB Server Engineering and security@mariadb.org