Clone Precedence: Exclude Tables or Profile large table data copy?

[jimsvn]

If you have a table (say, task or metric_instance for example) listed in the Clone Exclude Tables for a given Clone Profile, and you have no Clone Data Preserver defined for the same, and you check the "Exclude tables specified in Exclusion List" box in said profile, how does ServiceNow treat the Clone Profile selection for "Amount of data copied from large tables"? The choices for that selection are "Last 90 days" or "Full". Will ServiceNow always honor the exclusion (yielding an empty task or metric_instance table on the target in this example) or does that "large table data copy" profile option ever take precedence over the Clone Exclude Table entry?

[Michael Jones - · Accepted solution]

If you have setup an Exclude Table record for that profile for the Task table (for example), have the checkbox to exclude tables checked, and have last 90 days set for large tables, and no preserver for task, then at the end of the clone you will have an empty task table. 

It's a little unusual how they actually perform these actions, but you can get the gist of it here.

Basically you start off creating a file for anything you want to preserve on the target, then you clone the source (and you end up with all data in the instance for a time) - once that is done they truncate tables in the exclusion list (you wind up with 0 records for those tables) and then apply the file for preservers (add back data you wanted to keep). 

It's not called out specifically, but I believe that after they process exclusions and before preserved data is applied, they then delete records from the large tables (or not) to match what you selected. 

So in this case, exclusion wins because it targets the specific table and seems to occur before the large table process. 

I hope this helps!

If this was helpful, or correct, please be kind and mark the answer appropriately.

Michael Jones - Proud member of the GlideFast Consulting Team!