Limit to number of custom fields (columns) added to an OOB table?

[Sam Ogden]

Hi all,

I wanted to know if there was a limit to the number of custom fields that can be added to an OOB table for example demand.  I've received a request which has asked for quite a few new fields to be added (over 20) , but the table already has a lot of previously added custom fields (over 100).  

I've seen this document referring to a limit of 50 fields on custom tables - I think this is part of the newer licence model, but the document is referring to custom fields on custom tables and doesn't mention fields on existing platform tables that are not part of the exempt list such as incident, change, demand etc. 

Thanks

Sam

[Michael Jones - · Accepted solution]

The only hard restrictions that I've ever seen are related to custom tables and exempt tables; for core tables (those that are part of a paid subscription) I have not found a specific, numerical limit listed anywhere. I have, on the other hand, seen instances where there were more than 50 custom fields on the task table or a table extended from task.

The best "answer" that I have seen is in this thread: basically that there isn't an artificial limit but there is an underlying system limit that would eventually come into play. I personally think Chuck would have called out if there was a limit he was aware of. 

I will say this, from past DB experience (not specific to ServiceNow) that the maximum number of fields is usually higher than you would need, but is also usually less than the theoretical maximum depending on how much space is actually allocated to the DB and how growth is restricted. 

For your use case, I don't think you'll encounter any issues, other than perhaps slightly slower load times for records and maybe slow performance when adding the fields (depending on how many records you have). 

Hope this helps. 

If this was helpful or correct, please be kind and click appropriately!

Michael Jones - Proud member of the CloudPires Team!

[Sam Ogden]

Hi Michael,

Thanks for your detail above, it is very helpful.

I totally agree with your points above and also the points Chuck raises in the linked thread in terms of performance and actual usability of forms with too many fields in place.

Thanks

Sam

[DirkRedeker]

Hi 

Even if this is marked as correct, I want to mention, that you have a limit in Record-Size (in number fo bytes), which is (asaif) around 8KB.

This may become quite soon a limit if you add a high number of long string field.

Keep that in mind.

I guess, this is helpful as well.

BR

Dirk