Search query with Size(0)

[PoOoZaQ]

I am using Search to get docs according to some query.
What I would expect Size(0) to do is just return all the documents that answer the query.
Instead it returns the full object with 0 results, forcing me to execute the same query again with the number of "to-be" results.
Here is the code I wrote:

var resultsCount = _client.Search<JObject>(s => s.Query(q => q.Terms("string.ProgramId", ids))
            .Size(0));

var results = _client.Search<JObject>(s => s.Query(q => q.Terms("string.ProgramId", ids))
            .Size((int)resultsCount.Total));

Here is what I get in the first line:

Am I doing something wrong ?

[gmarz]

Hey @PoOoZaQ, that's not how the size parameter works. size is the number of results to return that match the query and thus setting it to 0 literally means return 0 documents.

This is a common problem. You want to return ALL of the results that match your query, but you're unsure of how many that actually is- could be 1, could be 1,000,000.

There are a few ways to handle this, and ultimately it depends on your application. I'd suggest checking out the sections on pagination and scan and scroll from the Elasticsearch: The Definitive Guide.

Hope that helps!