Data Contract

A data contract states what a producer supplies and what consumers may rely on. It covers meaning as well as structure: one row per order, a stable order identifier, an amount in the named currency’s minor units, and the time basis for each date. A list of column types cannot express all of those promises.

Name the producer and responsible owner, expected freshness, accepted updates and deletions, quality checks, and the response when a check fails. A daily total also needs a defined population: a timely file can still omit orders. State which checks block publication and which produce a visible warning.

Version the contract and identify affected consumers before a change. Adding a nullable column may preserve named-column queries but break a positional export. Changing the meaning of paid revenue can break a consumer without changing any column. Test actual readers and agree migration and notification steps.

A contract document is not enforcement. Producers need checks and operating procedures that implement it, and consumers need a way to detect violations. The Open Data Contract Standard provides a structured representation; adopting a representation does not by itself prove that delivered data satisfies it.

Reference: Open Data Contract Standard. See Designing End-to-End Data Architecture for the worked example.