Need help on understanding Filter Option in OData about odataorg.github.io

[dingeins]

Hi @maheshreeram,

This is a very good question.

I'm not sure if you are asking specifically about the behavior of a library (e.g. the behavior of the ASP.NET Web API for OData), or of the protocol. So I'll try to answer for both cases.

If you are using the ASP.NET Web API for OData, the default behavior when you use the [EnableQuery] attribute to automatically apply the query options to your storage is just the same as you described: it'll fetch all the data and apply the query option in memory, which I know is inefficient for you. But the library also provide the flexibility of enabling you to handle how the query options are applied yourself. You may check out the "Invoking Query Options Directly" section of this sample: http://www.asp.net/web-api/overview/odata-support-in-aspnet-web-api/supporting-odata-query-options to learn how to unwrap the ODataQueryOptions instances to get the actual query string and implement the business logic to apply the query to your storage before you getting any data from it.

If you're asking about the protocol, the protocol actually doesn't have any specification about if query options need to be applied prior to/after the retrieval of the data. It's up to you (the service implementer) to decide.

Hope you are satisfied with the answer.