[
https://issues.apache.org/jira/browse/HIVE-9298?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Jason Dere updated HIVE-9298:
-----------------------------
Attachment: HIVE-9298.1.patch
Initial patch. This adds a new serde property "timestamp.formats" to pass in a
comma-delimited list of alternate timestamp formats.
For example, the following adds 2 alternate formats: yyyy-MM-dd'T'HH:mm:ss, and
millis since Unix epoch, represented by the special case pattern "millis".
{noformat}
ALTER TABLE timestamp_formats SET SERDEPROPERTIES
("timestamp.formats"="yyyy-MM-dd'T'HH:mm:ss,millis");
{noformat}
I'm using Joda date parsing for this item. There are some advantages to using
the Joda parsing:
- The fractional seconds parsing for Joda seems to be the only one that looks
consistent with the fractional seconds parsing in the default Timestamp format.
For example in Java SimpleDateFormat, 0.1 = 0.001 = 1 millisecond, which is
inconsistent with the current Timestamp format.
- The pattern syntax is mostly compatible with SimpleDateFormat
- It supports adding multiple date formats
- It is extensible enough to add a custom parser to parse numeric values as
millis since Unix epoch (for HIVE-3844).
- It's not perfect either: Joda DateTime only supports up to millisecond
precision, so a custom timestamp format will only be able to support up to
millis precision as opposed to the default Timestamp format which can support
nanosecond precision.
> Support reading alternate timestamp formats
> -------------------------------------------
>
> Key: HIVE-9298
> URL: https://issues.apache.org/jira/browse/HIVE-9298
> Project: Hive
> Issue Type: Bug
> Components: Serializers/Deserializers
> Reporter: Jason Dere
> Assignee: Jason Dere
> Attachments: HIVE-9298.1.patch
>
>
> There are some users who want to be able to parse ISO-8601 timestamps, as
> well to set their own custom timestamp formats. We may be able to support
> this in LazySimpleSerDe through the use of a SerDe parameter to specify one
> or more alternative timestamp patterns to use to parse timestamp values from
> string.
> If we are doing this it might also be nice to work in support for HIVE-3844,
> to parse numeric strings as timestamp by treating the numeric value as millis
> since Unix epoch. This can be enabled through the SerDe params as well.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
