cast string as datetime with time zone results in loss of precision #8754
Description
Bug Report
Please answer these questions before submitting your issue. Thanks!
related to pingcap/tidb#49555
1. Minimal reproduce step (Required)
use test;
drop table if exists t;
create table t(a varchar(50));
alter table test.t set tiflash replica 1;
insert into t values ('2020-01-01 12:00:00.123456 +0600 PST');
insert into t values ('2020-01-01 12:00:00.123456 -0600 PST');
set tidb_allow_mpp=1;set tidb_enforce_mpp=1; set tidb_isolation_read_engines='tiflash';
select cast(a as datetime(3)) from t;
2. What did you expect to see? (Required)
+-------------------------+
| cast(a as datetime(3)) |
+-------------------------+
| 2020-01-01 12:00:00.123 |
| 2020-01-01 12:00:00.123 |
+-------------------------+
3. What did you see instead (Required)
+-------------------------+
| cast(a as datetime(3)) |
+-------------------------+
| 2020-01-01 12:00:00.000 |
| 2020-01-01 12:00:00.000 |
+-------------------------+
4. What is your TiFlash version? (Required)
v8.0.0-alpha-126-gc0476a0