Crawled Properties - Difference between Basic:15 and Created

Question

While configuring Managed Properties a collegue of mine didnt get the Created Crawled Property to work on his Managed Property.

Instead he used Basic:15 for the Created DateTime which just worked.

Can anyone explain to me the difference between those two? Why are there Basic Properties when there are equivalents for them as Created etc.?

Answer 1

The main difference is, that the basic properties are available before the first crawl. The others are the ones returned by the SharePoint search.

So your colleague maybe should start his crawler ;)

The basic crawled property are actually not "crawled", they are the representations of all primitive data values in sharepoint and are hardwired in the code / database.

The normal crawled properties are created for the found search results the same way for the build in content types as for custom content types. I'm quite sure the Created Field is part of the element contenttype, and since all elements in sharepoint derive from element, the first crawl will find it as long as you have at least 1 Web searched.

Some references:

• https://technet.microsoft.com/en-us/library/hh134087(v=office.14).aspx#Anchor_0
• https://blogs.technet.microsoft.com/anneste/2008/11/25/mystery-solved-crawled-properties-in-sharepoint-part-2/

Answer 2

Basically that is how Microsoft has created default crawled properties, they have divided into categories and given property name(integer like 10, 12,15 etc). And there is type of each property like text, integer, binary ,yes/no, date time etc). You can have single crawled property which can be mapped to multiple managed property. This might be required because similar crawled property might be mapped to different managed properties in different sites... Below content might be helpful for your understanding...

Below is content from Ref link

Some important excerpt.

Crawled properties in SharePoint are metadata that is extracted from documents during crawls and is based on the protocol handler used. Metadata includes information such as author, create date, subject, title, etc. Administrators can control which crawled properties are mapped to managed properties, and, in doing so, the end user search experience can be enhanced.

The dilemma comes into play when you’re trying to figure out which crawled property to map to a managed property. Several of the crawled properties do not have descriptive names (propID) but rather an integer for the name. This makes it impossible for one to know which crawled property could be mapped to a managed property.

there are 11 crawled property categories that are available out of the box. Some of the categories are self-explanatory while others may not be so clear. Given that, let’s take a look at what these categories represent.

Basic Category – can contain metadata that is associated with the gatherer, search, core, and storage property sets. In my environment, there are 10 different GUIDs (property sets) in the Basic Crawled Property Category.

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In your case Basic:15

Basic is category of crawled property 15 is Property name - This is the name the development team gave this property when the program was written. It is hard-coded in the program and cannot be changed.

This property set id will have guid..... Below is example for Basic:12, similar way you can do it for Basic:15

Property Set ID – A GUID that identifies the property set for the crawled property. Doing a search for the GUID B725F130-47EF-101A-A5F1-02608C9EEBAC and filtering the results for the Property Name of 12 yields several links to related content. One such link, on MSDN, provides a tremendous amount of information. This tells us that this property set is a System property and the propID of 12 is the file size