To be honest, I haven't found a way to include DocumentName into index. This is unfortunate, but maybe if you reach support (support@kentico.com) they could shed some light on it.
But adding a requred Title field for the existing Page Type shouldn't be hard. I see these steps required:
- In your Page Type add a new string field called Title and mark it as required
- In SQL run the following update to copy existing DocumentTitle into new Title field:
Code example for Dancing Goat MVC, Article Page Type and new Title column:
UPDATE
DancingGoatMvc_Article
SET
DancingGoatMvc_Article.Title = View_CMS_Tree_Joined.DocumentName
FROM
View_CMS_Tree_Joined
INNER JOIN DancingGoatMvc_Article
ON View_CMS_Tree_Joined.DocumentForeignKeyValue = DancingGoatMvc_Article.ArticleID
WHERE View_CMS_Tree_Joined.ClassName = 'DancingGoatMvc.Article'
- (optional) And to avoid field duplication, in Fields tab of your Page Type you can select new Title field in the dropdown "Page name source field". That's it!