Arrow Errors with MongoDB

1

Hi everyone,

I recently installed Dremio, and connected it to MongoDB. Reading some collections work, while others throw an error related to Apache Arrow. Has anyone else encountered a similar problem as below?

Vector already exists: Existing[NullableMapVector], Requested[org.apache.arrow.vector.types.pojo.FieldType@21788cbc]

Thanks

2

Is it possible for you to share your query profile?

Instructions are here: https://www.dremio.com/tutorials/share-query-profile/

Also, it would be good to know what version of MongoDB, and your topology (sharded, connected to secondary, etc).

3

This is a known issue, and will be fixed in an upcoming release. I will post here once that happens.

4

Thanks @steven, @kelly I’m using MongoDB 3.4.5, single node replica.

Out of interest, does using Apache Arrow result in any perf difference in MongoDB reads? I know it should with SQL.

5

I have same issue, when I connect MongoDB to dremio, some collections work, while others throw the following error. What should I do?

Vector already exists: Existing[NullableMapVector], Requested[org.apache.arrow.vector.types.pojo.FieldType@4e9add81]

Thanks

6

@GreeYoN Can you please upload the job profile for the failed job?