Question

In RavenDB my document (ID = 1234) is

   "datacontainer": {
      "data": [
        {
          "@idx": "1",
          "@idy": "a",
          "value": {
            "#text": "test 2010"
          }
        },
        {
          "@idx": "2",
          "@idy": "b",
          "value": {
            "#text": "test 2011"
          }
        },
        {
          "@idx": "3",
          "@idy": "c",
          "value": {
            "#text": "test 2012"
          }
        }
      ]
   }

I want to create an Index, where I choose my favourite values (for example idx = "2" and idy = "b") and the output will be:

(ID, value_text) = (1234, "test 2011")

Now I can select a single element and check its value in Linq:

where p.datacontainer.data[0]["@idx"] == "2" && p.datacontainer.data[0]["@idy"] == "b"

How can I search the right element in my list?

Answer 1

I solved my problem! In RavenDB the index, called “MyIndex”, is:

Map:

from p in docs
select new  
{  Id = p.id, 
   M = p.dataApplication.datacontainer.data.Where(x => x["@idx"] == "2").First(x => x["@idy"] == "b").value["#text"] 
};

Reduce:

 from test in results
 group test by new {test.Id, test.M   } into g
 select new { g.Key.Id, g.Key.M }

Now I can use this Index in my queries, so I will search for a document that contains a particular value, for example:

 var results = from p in session.Query<QueryResult>("MyIndex")
               where p.M == "test 2011"
               select p;

Maybe there is a better solution, but now it works!