I recently came across a problem in SharePoint Search which had me flumuxed for a while, looking at the search results below is displayed the results of 2 list items, 1 with a PowerPoint attachment and 1 without any attachment. The 1 with an attachment is showing an extracted document property as the Title managed property value rather than using the listitem’s Title column value;
Removing all of the document properties from the attached file had no effect, as the search result Title text shown is the text of PowerPoint documents first slide.
Managed Property Mappings
Looking at the managed property mappings for the Title managed property shows the following crawled property mappings;
As you can see the MetadataExtractorTitle crawled property is further up the list than the (SharePoint listitem) ows_Title crawled property, so I then tried moving the ows_Title crawled property right to the top of the list which you’d expect to work given the description of crawled property mappings;
Include content from the first crawled property that is not empty, based on the specified order.
This, however, didn’t work either and the search results showed the same.
I then tried moving the ows_Title crawled property to the top and the MetadataExtractorTitle crawled property right to the bottom of the list of crawled property mappings for the Title managed property and this did work, search results showed the Title value from the list item’s Title column;
The search results now show the correct Title value;
The reason as far as I can understand is that, when considering the crawled property to use as the source of the value for a managed property, the crawled property should have a non-empty value, and then when multiple crawled properties have a value, the weight of the crawled property is taken into consideration to determine the final crawled property to use. It would seem that the MetadataExtractorTitle property has a higher weight than ows_Title in this case.