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https://issues.apache.org/jira/browse/KYLIN-749?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14990977#comment-14990977
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hongbin ma commented on KYLIN-749:
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timestamp type was not well supported in 1.x versions. In 2.x versions, as we
started to support streaming cases, timestamp type becomes important. We added
support of timestamp by adding a special dictionary called TimeStrDictionary.
TimeStrDictionary fits into current dictionary encoding system, which requires
encoding anything into a 32bit integer. Since timestamp is usually represented
as a 64bit long in java(allowing precision of millisecond), we had to make a
little tradeoff here to fit a timestamp value into a 32 bit integer:
In kylin timestamp type only keeps precision of second. so a 32 bit integer can
represent maximum timestamp of Integer.Max * 1000, which is 2038-01-19
03:14:07, this will be enough for the predictable future use case.
> support timestamp type in II and cube
> -------------------------------------
>
> Key: KYLIN-749
> URL: https://issues.apache.org/jira/browse/KYLIN-749
> Project: Kylin
> Issue Type: New Feature
> Reporter: hongbin ma
> Assignee: hongbin ma
> Fix For: 2.0
>
>
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