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Aihua Xu commented on HIVE-19040: --------------------------------- OK. That makes more sense. > get_partitions_by_expr() implementation in HiveMetaStore causes backward > incompatibility easily > ------------------------------------------------------------------------------------------------ > > Key: HIVE-19040 > URL: https://issues.apache.org/jira/browse/HIVE-19040 > Project: Hive > Issue Type: Improvement > Components: Standalone Metastore > Affects Versions: 2.0.0 > Reporter: Aihua Xu > Priority: Major > > In the HiveMetaStore implementation of {{public PartitionsByExprResult > get_partitions_by_expr(PartitionsByExprRequest req) throws TException}} , an > expression is serialized into byte array from the client side and passed > through PartitionsByExprRequest. Then HMS will deserialize back into the > expression and filter the partitions by it. > Such partition filtering expression can contain various UDFs. If there are > some changes to one of the UDFs between different Hive versions, HS2 on the > older version will serialize the expression in old format which won't be able > to be deserialized by HMS on the newer version. One example of that is, > GenericUDFIn class adds {{transient}} to the field constantInSet which will > cause such incompatibility. > One approach I'm thinking of is, instead of converting the expression object > to byte array, we can pass the expression string directly. > > > > > -- This message was sent by Atlassian JIRA (v7.6.3#76005)