If your input file contains field names that match those names that Address Coder uses for items it will be appending to your file, the data in those existing columns will be overwritten. This does not apply if your output is fixed length text files.
These stub names include (but are not limited to) GEOCODE, GEOLEVEL, STATE_FIPS, COUNTYFIPS, TAPESTRY, TAPESTDESC, TAP_LEVEL, LONGITUDE, LATITUDE, CBSA_CODE, CBSA_NAME, and MATCH_CODE.
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