Custom Columns are One Part of the Mystery of SharePoint Search

Understanding how SharePoint Online search works is one of the learning curves faced by many Microsoft 365 tenant administrators. Because search is so important to SharePoint, this topic is well-covered ground for people who worked with SharePoint Server (on-premises). The magic that melds managed properties, crawled properties, mapping, custom cpolumns, indexes, and so on into search doesn’t hold any mysteries.

Things are different for those who come to SharePoint because of its core role within Microsoft 365. SharePoint Online is not the center of an ecosystem like SharePoint Server is. Like Exchange Online delivers email services, the cloud version of SharePoint takes on a completely different role as the provider of document management services to other workloads, like Teams. The different role doesn’t make search any less important. People still want to find files quickly and easily but competing demands from across Microsoft 365 mean that administrators sometimes pay less attention to the finer details of search. After all, search just works in the cloud…

Generally, SharePoint search does just work. Sometimes complexities do exist, like finding out how to find files with a specific sensitivity label. Although users mightn’t want to look for labelled files, administrators might need this knowledge to find labelled files in eDiscovery searches, and that’s why some knowledge about how search works is a good skill to acquire, even for non-SharePoint people. In my case, it helped me to maximize the advantage of creating a custom column for a site.

Creating a Custom Column

SharePoint Online is basically a big Azure SQL application based on a database holding many lists (tables). The lists hold data in items with the information for each item stored in columns (fields). SharePoint allows site administrators to define new custom columns at a site or library level. I use this feature to track the topic areas for articles I publish on different sites.

In general, defining custom columns at site level is recommended because the custom columns can then be used in any library. Figure 1 shows the properties of a custom site column called RAInfo.

After creating the site custom column, use the Add from existing site columns option in Library settings to add the column to a document library. Once the column is added to a library, it can be added to the view that exposes file metadata and edited there (or updated programmatically using a Graph API or SDK cmdlet).

Remaining in library settings, go to Indexed columns and add the new custom column as an index. SharePoint libraries support up to 20 indices.

Using Custom Columns

One of the nice things about custom columns is that SharePoint supports their use in filters. In Figure 2 we see that the filter picker shows the values entered for files in the RAInfo custom column. Selecting the desired values for the RAInfo column helps SharePoint to find and display files that meet the filter criteria. Of course, filtering only works if users remember to enter the necessary information for files.

Users can also input a custom column value (for instance, “RA001”) into the search box to search the library for matching files. Because the custom column is part of the document metadata, SharePoint search can use it to find files.

Making Custom Columns More Searchable

The search against document metadata finds matches against any property containing the value. A further step is required to allow searches against the custom column be more specific.

When you create a custom site column, SharePoint Online creates a managed property named using the form CustomColumnName + “OWSText.” In this case, the managed property is called “RAInfoOWSText.” SharePoint also creates a crawled property with the name OWS_Q_TEXT_CustomColumnName, or OWS_Q_TEXT_RAInfo in our case. The crawled property is what SharePoint search extracts from a site.

To allow search to use the managed property, it’s critical to map the managed property to the crawled property and wait for indexing to complete. Once indexing is complete, you can input RAInfoOWSText:RA001 into the search box. This command instructs SharePoint to search against the RAInfoOWSText managed property.

Not everyone will appreciate working with what seems to be odd column names. To solve the problem, go to Site Information, then View all site settings, and select the Search schema. You can now create an alias for the custom column, hopefully giving the column a name that makes more sense to regular users. In Figure 3, I’ve assigned RAInfo as the alias for the RAInforOWSText managed property.

Adding an alias to disguise some of the complexities of SharePoint search is a small but useful step to take. Now users can input search terms like RAInfo:RA003 (Figure 4) into the search box instead of RAInfoOWSText:RA003 and find the same information.

Take Your Time

One thing that you’ll discover when tweaking SharePoint search is that it takes hours and sometimes days for changes to become active in a site. Users need to populate values in the custom column and search needs to index those values, including respecting the changes that you might have made like adding an alias for a managed property. You can force the issue somewhat by requesting a reindex of the document library (in library advanced settings), but SharePoint Online can’t be rushed too much.

Take your time and everything will work in the end. At least, it did for me.