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To help clarify the purpose of each field, I use the FGDC Street Address Data Standard.
Click here is the latest and most complete reference or you can just take a look at draft 2 which is usually adequate.
Click Here here for number suffix.
Click Here here for unit number.
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EAS Field: address_base.base_address_id (int)
XML Field: base_address_id
FGDC Field: na
AVS Field: na
Example:
Comment: EAS primary key
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