Profile format changelog

The generated report.json identifies its contract with two independent fields:

{
  "format_version": "0.1.0a",
  "format_revision": 2
}

format_version names the experimental compatibility family. It remains 0.1.0a throughout the Tabalyst 0.1.0aX application series. format_revision is a monotonic integer incremented for meaningful structural or semantic changes. It does not change for report styling, documentation, performance improvements, or corrections that preserve the JSON contract.

Alpha revisions may be incompatible. No automatic migration is provided yet.

Revision 1 - 2026-09-18

• Established the first explicitly tracked alpha profile contract.
• Includes dataset/source metadata, effective configuration, quality summary, issues, raw preview rows, and global column profiles.
• Column profiles include normalization, inferred and semantic types, errors, occurrences, bounded examples, numeric statistics, date analysis, and string length statistics.
• Added format_version and monotonic format_revision identifiers.

Revision 2 - 2026-09-23

• Materialized per-column with_issues, defined as missing values or inferred type mixed.
• Added dataset-level physical/semantic type distributions and report section counts.
• Added dataset-level date aggregates and per-date-column ambiguity summaries.
• Added present counts and percentages to date profiles, numeric ranges, and relative/representative string-length values used by the report.