Amazon Cloudsearch : Filter if exists

Question

I have an amazon cloudsearch domain. The aim is to filter if the field 'language' exists. Not all objects have a language, and I want to have the ones which do have a language filtered, but the ones that do not have any language to also be returned.

I want to filter with ( or language:'en' language:null )

However null cannot be passed within a string.

Is this possible? If so how would it be done.

Answer 1

If you are willing to use the Lucene query parser you can express your query like this:

(*:* OR -language:*) OR language:en

Note: The funky (*:* OR ...) construct is necessary because of the way Lucene treats negated OR clauses.

In general, you can filter by existence / non-existence of a field with the Lucene query parser:

All documents containing field: field:[* TO *]

All documents not containing field: -field:[* TO *]

Note: If field is textual (text or literal datatypes) you don't need range queries and you can shorten the above to:

field:* and -field:*

Answer 2

I looked elsewhere aswell, it seems :

The simplest way to do that, is to set a default value for the field, and then use that value for your null.

For example, set the default to the string "null", then you can easily test for that.

I believe you can add a default value, and re-index, and that should reapply the default.