sgr's main purpose is to build, extend, manipulate and share data images. Data
images are essentially snapshots of a PostgreSQL schema at a given point in
time, much like Docker images are snapshots of the filesystem.
An image consists of tables. Tables are composed of
content-addressable objects, so that when multiple images contain the
same table (or overlapping subsets of it),
sgr only stores one copy of the
You can create Splitgraph images in multiple ways. You can “check out” any image
into a PostgreSQL schema and interact with it using any PostgreSQL client.
will capture your changes to the data,
and then you can commit them as delta-compressed changesets that you can package
into new images.
You can also create Splitgraph images using a declarative Splitfile language, which offers a similar experience to Dockerfiles, including a caching system for efficient rebuilds that execute only when upstream sources change.
Under the hood, Splitgraph image metadata (including parents and provenance) is
splitgraph_meta.images table and table metadata is stored in