I have a shapefile of all the addresses in a city and a table of survey results for a sample of addresses, with NO spatial aspect. I am asked to make the survey data spatial, so used a simple join based on address in the table to the address shapefile.
After I performed the join, I discovered that 2,558 of the ~30,000 survey results rows did NOT join. Some of these are due to misspellings in the survey address list, but the vast majority of addresses seem to be present and accurate in BOTH fields. When I search for the addresses manually, they are in both of the fields used to join, and are identical and accurate. I trimmed the fields in both ArcGIS and in Excel, so it shouldn't be leading or trailing spaces.
I am at a complete loss at what could cause identical join values to NOT join. Is there something obvious I'm missing here? Any ideas?