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https://issues.apache.org/jira/browse/FLINK-16938?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17074397#comment-17074397
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YufeiLiu edited comment on FLINK-16938 at 4/3/20, 8:26 AM:
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Hi [~jark], I think timestamp doesn't have timezone, there are same timestamp
in every timezone at same time, which is millisecond offset in UTC, but format
to LocalDateTime need timezone offset.
{{LocalDateTime}} is entirely equals to date string, like
'2020-04-03T16:00:00', we can't convert it to timestamp without timezone
information.
was (Author: liuyufei):
Hi [~jark], I think timestamp doesn't have timezone, there are same timestamp
in every timezone at same time, which is millisecond offset in UTC, but format
to LocalDateTime need timezone offset.
{{LocalDateTime}} is entirely equals to date string, like
'2020-04-03T16:00:00', we can't convert it to timestamp without timezone
information.
{code}
> SqlTimestamp has lag when convert long to Timestamp
> ---------------------------------------------------
>
> Key: FLINK-16938
> URL: https://issues.apache.org/jira/browse/FLINK-16938
> Project: Flink
> Issue Type: Bug
> Components: Table SQL / Planner
> Affects Versions: 1.10.0
> Reporter: YufeiLiu
> Priority: Major
>
> When I set rowtime attribute by using expression 'column.rowtime' , and
> result type is sql.Timestamp, the result will have lag which is equals with
> default timezone offset.
> {code:java}
> tEnv.fromDataStream(stream, "user_action_time.rowtime, user_name, data");
> {code}
> I look into the conversion logic, the field was go through 'long ->
> SqlTimestamp -> Timestamp' conversion.
> {code:java}
> long from = System.currentTimeMillis();
> long to = SqlTimestamp
> .fromEpochMillis(from)
> .toTimestamp()
> .getTime();
> {code}
> The result is {{from!=to}}. In {{SqlTimestamp.toTimestamp()}} using
> {{Timestamp.valueOf(LocalDateTime dateTime)}} which is contain timezone
> infomation, will casue time lag.
> From Timestamp to Timestamp not have this issue, but convert Datastream to
> Table is use StreamRecord.timestamp as rowtime field.
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