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https://issues.apache.org/jira/browse/HIVE-25104?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17342660#comment-17342660
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Stamatis Zampetakis commented on HIVE-25104:
--------------------------------------------
HIVE-24074 describes the same problem and adapts the Parquet/Avro *readers* to
render timestamps taking into account these differences between old/new java
classes.
With this in place, reading values from older versions of Hive produces more or
less the expected results. However, the writers are not changed as part of
HIVE-24074 which makes this issue visible in the first place.
> Backward incompatible timestamp serialization in Parquet for certain timezones
> ------------------------------------------------------------------------------
>
> Key: HIVE-25104
> URL: https://issues.apache.org/jira/browse/HIVE-25104
> Project: Hive
> Issue Type: Bug
> Components: Serializers/Deserializers
> Affects Versions: 3.1.2
> Reporter: Stamatis Zampetakis
> Assignee: Stamatis Zampetakis
> Priority: Major
>
> HIVE-12192, HIVE-20007 changed the way that timestamp computations are
> performed and to some extend how timestamps are serialized and deserialized
> in files (Parquet, Avro, Orc).
> In versions that include HIVE-12192 or HIVE-20007 the serialization in
> Parquet files is not backwards compatible. In other words writing timestamps
> with a version of Hive that includes HIVE-12192/HIVE-20007 and reading them
> with another (not including the previous issues) may lead to different
> results depending on the default timezone of the system.
> Consider the following scenario where the default system timezone is set to
> US/Pacific.
> At apache/master commit 37f13b02dff94e310d77febd60f93d5a205254d3
> {code:sql}
> CREATE EXTERNAL TABLE employee(eid INT,birth timestamp) STORED AS PARQUET
> LOCATION '/tmp/hiveexttbl/employee';
> INSERT INTO employee VALUES (1, '1880-01-01 00:00:00');
> INSERT INTO employee VALUES (2, '1884-01-01 00:00:00');
> INSERT INTO employee VALUES (3, '1990-01-01 00:00:00');
> SELECT * FROM employee;
> {code}
> |1|1880-01-01 00:00:00|
> |2|1884-01-01 00:00:00|
> |3|1990-01-01 00:00:00|
> At apache/branch-2.3 commit 324f9faf12d4b91a9359391810cb3312c004d356
> {code:sql}
> CREATE EXTERNAL TABLE employee(eid INT,birth timestamp) STORED AS PARQUET
> LOCATION '/tmp/hiveexttbl/employee';
> SELECT * FROM employee;
> {code}
> |1|1879-12-31 23:52:58|
> |2|1884-01-01 00:00:00|
> |3|1990-01-01 00:00:00|
> The timestamp for {{eid=1}} in branch-2.3 is different from the one in master.
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