datom 0.1.1

Initial CRAN release. datom provides version-controlled data management for reproducible scientific and clinical workflows — tables are tracked as code in git while actual data lives in cloud storage (S3) or a local filesystem backend.

datom is experimental: the API may change without a deprecation cycle until it reaches a stable release.

datom requires R >= 4.1.0.

Table identity: the datom-cv1 canonical hash

Table identity is defined by a canonical hash of a table’s values (datom-cv1), not by the bytes of its parquet serialization. Hashing the serialization tied identity to the writer: an arrow upgrade or a different compression default produced different bytes for identical data, and therefore a spurious new version. See vignette("design-version-shas") for the model and the identity decisions.

• Pre-release data_sha values change, and there is no migration path. Any table written by a pre-release build carries a data_sha computed by the old algorithm. Those values are not recomputed, converted, or reconciled — pilots should re-onboard their data.
• Three SHAs are now recorded per table: data_sha (content identity), metadata_sha (the version you pass to datom_read(version = )), and parquet_sha (the stored object’s SHA-256, verified on read before parsing).
• metadata.json gains hash_algo, parquet_sha, and column_hashes — an ordered per-column digest index from which data_sha can be re-derived without downloading data.

Deliberate narrowings

Three capabilities were narrowed on purpose relative to pre-release behaviour.

• List and exotic columns are refused. A column must be a supported atomic type; list columns and exotic classes now abort the write with actionable

  advice. See datom_check_hashable() for a pre-flight check.

• datom_sync() accepts only allowlisted formats. Flat tabular files only (csv, tsv, parquet, sas7bdat, xpt, sav, dta, xls, xlsx). Read unsupported formats yourself and pass the data frame to datom_write().

• Internal sort_columns / sort_rows removed. Row and column order are significant; sort explicitly before writing if order should not matter.

Full API

See the reference index for the complete exported surface at 0.1.0.