Sorting

Tip: There are many examples of sorting in the FluentApiTests source code to use as examples/reference.

Score

By default search results are ordered by Score descending so there's nothing specific that needs to be done to support this. If you use a different sorting operation then the Score value will be 0 for all results.

Custom sorting

Any field that is a numerical or date based is automatically sortable. To make text based fields sortable you need to explicitly opt-in for that behavior. By default all fields are FieldDefinitionTypes.FullText which are not sortable. To make a text field sortable it needs to be FieldDefinitionTypes.FullTextSortable.

You cannot sort on both the score and a custom field.

Sorting is done by either the OrderBy or OrderByDescending methods using a SortableField and a SortType. The SortType should typically match the field definition type (i.e. Int, Long, Double, etc...)

• For FieldDefinitionTypes.FullTextSortable use SortType.String
• For FieldDefinitionTypes.DateTime use SortType.Long.

Example:

 var searcher = indexer.GetSearcher();

 var orderedResults = searcher
   .CreateQuery("content")
   .Field("writerName", "administrator")
   .OrderBy(new SortableField("name", SortType.String))
   .Execute();
   
var orderedDescendingResults = searcher
   .CreateQuery("content")
   .Field("writerName", "administrator")
   .OrderByDescending(new SortableField("name", SortType.String))
   .Execute();