Great Expectations

Overview

Great Expectations (GX) lets you define, run, and document data quality checks. GX 1.0 (released 2025) was a ground-up rewrite: the global DataContext/CLI-driven project from the 0.18 series is gone, replaced by an in-code context you build with gx.get_context(). There is no more great_expectations init scaffolding step — if an older tutorial opens with that command, it is describing the pre-1.0 API and the rest of its code will not run.

Current version is GX Core 1.23 (pip show great_expectations). The core flow is: Data Source → Data Asset → Batch Definition → Batch, then Expectation Suite → Validation Definition → Checkpoint.

Instructions

Install

python -m venv .venv && source .venv/bin/activate
pip install great_expectations
# SQL sources need their driver too, e.g.:
pip install psycopg2-binary