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Quickstart

Three minutes, no cloud account. The repo ships a runnable demo and a small real table.

On a real table (no setup)

The repo includes fixtures/taxi-nyc, a small Delta table written from public NYC TLC yellow-taxi data, partitioned by pickup date:

# date is the partition column: directory-level pruning, exact
delta-explain fixtures/taxi-nyc -w "pickup_date = '2024-01-03'"

# date prunes partitions, fare prunes on min/max stats within them
delta-explain fixtures/taxi-nyc -w "pickup_date = '2024-01-03' AND fare_amount > 50"

# a predicate that does NOT prune - and the tool tells you why
delta-explain fixtures/taxi-nyc -w "PULocationID = 132" --explain-why

That last command is the point of the tool: the pickup-zone column is not clustered, so data skipping cannot help, and --explain-why says so with a fix. See Why isn't it pruning?.

The full demo (Docker)

examples/quickstart/ brings up a MinIO + demo-table stack and walks the gate story end to end (a healthy table, a layout regression the gate catches, the JSON contract). Follow its README:

cd examples/quickstart
docker compose up -d
# then the commands in examples/quickstart/README.md

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