sdks/python/apache_beam/testing/benchmarks/tpcds/README.md

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# Apache Beam Python TPC-DS Benchmark & Evaluation Suite

This package provides a Python TPC-DS benchmark and correctness suite that uses:
- **Cross-language Beam SQL Expansion Service** (`:sdks:java:extensions:sql:expansion-service:shadowJar`) via `apache_beam.transforms.sql.SqlTransform`
- **Prism Runner** via `PrismRunner`
- **Java TPC-DS schemas and queries** copied into `tpcds/build` via Gradle (`copyTpcdsResources`)
- **GCS TPC-DS datasets** (`gs://beam-tpcds/datasets/text/10MB`, `1GB`, `10GB`, `100GB`)

## Running via Gradle

The Gradle tasks in `:sdks:python:apache_beam:testing:benchmarks:tpcds` automatically copy the Java TPC-DS schemas and queries into `tpcds/build` and build the Java SQL expansion service shadow jar before running Python.

### 1. Run the Supported TPC-DS Queries on the 10MB Dataset

```bash
./gradlew :sdks:python:apache_beam:testing:benchmarks:tpcds:run \
  -Ptpcds.args="--queries=supported --data_size=10MB"
```

### 2. Run the 13 Canonical Multi-Table Queries

```bash
./gradlew :sdks:python:apache_beam:testing:benchmarks:tpcds:run \
  -Ptpcds.args="--queries=canonical13 --data_size=10MB"
```

### 3. Run Specific Queries on 1GB GCS Data

```bash
./gradlew :sdks:python:apache_beam:testing:benchmarks:tpcds:run \
  -Ptpcds.args="--queries=3,7,42,43,52,55,96 --data_size=1GB --results_directory=/tmp/tpcds_results"
```

### 4. Run the Pytest Evaluation Suite

```bash
./gradlew :sdks:python:apache_beam:testing:benchmarks:tpcds:pytest
```