Thanks Sorabh, for the analysis and the pointers to the relevant code. Doing the version check check for client and server would be the right thing to do but probably too disruptive at this stage of the release. We should do it for the next release. For 1.13, could the change of the $values$ be reverted to the actual field name of the ValueVector ? Since the DRILL-6049 was a 'hygiene' change, I would think that doing this revert should not break anything...but I am not fully sure of this.
-Aman On Tue, Mar 6, 2018 at 8:01 PM, Sorabh Hamirwasia <shamirwa...@mapr.com> wrote: > Hi All, > > The root cause for DRILL-6216 is due to a recent change made as part of > https://issues.apache.org/jira/browse/DRILL-6049. With this PR a default > field name for values ValueVector inside any NullableValueVector was > introduced which is $values$ [1]. Before this PR the values ValueVector > field name was same as the field name of actual NullableValueVector holding > it [2]. In the load method of certain ValueVectors like BigIntVector there > is an equality check for the ValueVector field name and metadata.name_part > name [3]. > > In setup where Drillbit and DrillClient are running in different version > (between 1.12 and 1.13) the equality check in load method will fail. For > example: When server is running 1.13 and client is on 1.12, in that case > the record batch from server side will come with NullableValueVector (NV1 > with field name as num_val) but with it's values ValueVector field name as > $values$. When on client side corresponding NullableValueVector (NV2) is > created it will use the actual field name (num_val) for values ValueVector. > After calling load on received NullableValueVector NV2 with metadata > information from server that internally alls load on values ValueVector and > the check fails since ($values$ != num_val). > > > Since the change is in template of ValueVector, to fix this issue both > client and server needs to identify their respective version on which they > are running and choose the field name for values ValueVector > correspondingly. Given DRILL-6049 touches huge sets of files I am also not > sure what are the other impacts with it. It would be great to discuss on > how we should proceed with this issue before making any further change. > > > [1]: https://github.com/apache/drill/blob/master/exec/vector/ > src/main/java/org/apache/drill/exec/vector/ValueVector.java#L92 > > https://github.com/apache/drill/blob/master/exec/vector/ > src/main/codegen/templates/NullableValueVectors.java#L82 > > [2]:https://github.com/apache/drill/blob/1.12.0/exec/vector/ > src/main/codegen/templates/NullableValueVectors.java#L70 > > [3]: https://github.com/apache/drill/blob/1.12.0/exec/vector/ > src/main/codegen/templates/FixedValueVectors.java#L238 > > > Thanks, > > Sorabh > >
