A key override changes the Platform’s choice of best key for matching connected datasets, while using multiple key overrides can improve the match rate.
For example, you might have a pair of datasets with two keys: one containing relatively out-of-date data, and one containing data that is known to be current. Normally, InfoSum Platform will select the key with the higher key fill rate. Using a key override, you can tell InfoSum Platform to use a different key even if its fill rate is lower.
Counting and matching prioritised keys in key overrides
Overriding the Platform's automatically selected key creates a lower match rate, but adding multiple common keys in the prioritised key field can improve the match rate. If you choose to match on multiple keys, a match on any key counts towards the audience total (with multiple matches for a record counted only once) because it uses the OR function. For this reason, the total audience count will always be the same, regardless of the order in which prioritised keys are specified.