Hello everyone.
I'm using Customer Insights to match data over multiple data sets and finding some matching rules working intermittently.
The rules that have issues are of the form Full Name + Date of Birth + Postcode.
Entries are the same data types and set to the correct field type in both data sets.
The values are considered a match when joining or using UNION on those three columns using SQL in the source database.
The same values do form a match with the same rule when deduplicating in a single entity. We add un-matched records on to the primary record source and subsequent matching runs take them back out again at the deduplication phase.
The matching rule does not fail for all records (approximately 10% fail to match from a data set of around 500 rows) but does appear to consistently fail for specific sets of values.
I've tried various combinations of options within the Normalize drop down with no impact.
There's nothing visibly different about the combinations that don't match. I've checked for hidden characters, line breaks, non breaking spaces etc.
Any suggestion on further steps I can perform to either resolve the issue or identify the cause?