The matching ID fields are identical, there are no extraneous spaces or anything like that. I exported the feature class and table to a gdb, and it joins all but one record (still no difference in the IDs). I need to do this for multiple feature classes. It makes no sense to me that it works in a gdb but not in an mdb.
And yes, the data has to be in a mdb - it's for modelling software.
The field types are identical - string with lengths of 32 in both. No spaces, no dashes, fields start with a letter.
So I just tried joining the exported feature class with the original dbf, and that only matches 90%. But when they are in the same gdb, it does all but one record.
"C_LRC_RCD2_100" is a matching record.
"C_LRC_RCD2_MT_20" is a non-matching record.
Using ArcGIS 10.3.1
Could it have something to do with the feature class join field not being indexed?
It is a simple, one-to-one join
Text from 'Validate Join':
All field and datasource validation tasks were completed successfully.
The number of matching records for the join: - 288 of 317 records matched by joining [INFO_COND_ID] from with [ID] from . Matching records may not appear in table view due to join validation errors.
"C_LRC_RCD2_MT_2" is a matching record, "C_LRC_RCD2_MT_20" is a non-matching record: