Proper filter spec for selecting null values

Hi folks,

I’m having some issues with a Druid query that isn’t returning the results i expect. What is the proper filter spec to use to select data that has no / null / empty-string value for a particular dimension?

I’ve tried the following filters:

{
“type”: “selector”,
“dimension”: “field”,
“value”: “”
}

``

{
“type”: “selector”,
“dimension”: “field”,
“value”: null
}

``

{
“type”: “selector”,
“dimension”: “field”,
}

``

My understanding is that these three filters should actually be equivalent - and they perform the same in the sense that they all return the same wrong results :slight_smile: When this filter is included, no results are returned even though an unfiltered group-by query that groups by the “field” dimension shows null values for that dimension.

This issue seems to be related to https://groups.google.com/forum/#!msg/druid-user/FrQ_W8nYSWQ/LS49sKEA30IJ - ideally I’d like to be able to wrap a NOT filter around the selector filter as well. I noticed a PR containing some null-value-related fixes but as we’re running 0.8.1 I am pretty sure those are already in place.

Thanks,

Mike

Yes it is the same filter
i think you are missing this fix https://github.com/himanshug/druid/commit/fa5c3bb014e557ee6dc6f2278f2ed64cf1584700

can you try updating to the latest RC ?