What is a File Definition?

File definitions and EDI mapping are two sides of the same coin — one describes the raw data coming in or going out, the other describes what to do with it.

Here's the overall picture — the flow from source file through definition to EDI output:

A file definition and an EDI map are separate but dependent artifacts — the definition must exist before the map can be built.

What a file definition is

A file definition is a schema that tells your translation engine exactly how to read (or write) a non-EDI file. It captures:

• Record structure — what constitutes a header record, a detail record, a trailer record, and how to tell them apart (a record type code in position 1, for example)
• Field layout — for fixed-width: the start position and length of every field. For delimited: the delimiter character, field sequence, and optional qualifier. For XML/JSON: the element path and expected data type
• Data types and formats — character, numeric, date (YYYYMMDD vs MMDDYY), packed decimal, signed/unsigned
• Conditional logic — which records are mandatory, which are optional, how many times a detail record can repeat