OData query $filter conditions and case-sensitivity

Question

Does OData specify whether filter conditions on string fields are to be evaluated case-sensitively or case-insensitively?

Example: (from the docs)

/S         


        

Answer 1

It doesn't depend on database. Even if you perform query against database in case in-sensitive way then OData will do his own additional filtering and filter your data out.

Answer 2

It is now possible to do case insensitive compare by setting EnableCaseInsensitive = true on the ODataUriResolver. I used this with Microsoft.AspNetCore.OData 7.1.0.

     var oDataUriParser = new ODataUriParser(model, uri)
     {
        Resolver = new ODataUriResolver { EnableCaseInsensitive = true}
     };

Source: https://github.com/OData/WebApi/issues/812

Answer 3

I would expect this is depended on your database collation setting, as the odata service is just performing a query. If Vitek's answer is correct, then odata is doing some post query filtering on the result set, and that should be strange, right?

Answer 4

The "eq" operator is supposed to be case sensitive. Usage of tolower (or toupper) is the currently recommended way of doing this.