How would I update an SQL record in Blueprint

I have recently migrated from DataTables to an SQL database and have it running fine except that I am not sure how i would implement updating a single record’s particular field i.e John Smith’s age from 45 to 46. The current update node would seem to change a field for all records in a table; unless you do it by inputting an SQL query into the condition pin - but i wouldn’t know what syntax to use.
Any assistance would be greatly appreciated.