Help Understanding this Script
The script below identifies a way to mark the 1st occurrence of a record with a specific value in a field that appears in a group of imported records. e.g. If multiple records contain a field with "Ray", this script will identify the first imported record with "Ray" in the field being monitored. I've included the entire script but highlighted in blue the portion that makes the relationship and calc field work
It uses a self join and a calculated field to set the value of a field c_FirstAppearance based on the RecordID of the records after import.
The script works but I cannot understand why. The calc field enters a 1 into c_FirstAppearance if the RecordID in Table 1 = the Record ID in table 2. Since this is a self join, aren’t these values always the same? Why does this relationship work?