tpcds/README.md

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# TPC-DS

## Generating TPC-DS data with Spark

Databricks provides tooling for generating TPC-DS datasets in a Spark cluster:

[https://github.com/databricks/spark-sql-perf](https://github.com/databricks/spark-sql-perf)

## Generating TPC-DS data without Spark

For local development and testing, we provide a Python script to generate TPC-DS CSV data and convert it into Parquet,
using DataFusion.

Download the TPC-DS data generator (tpc-ds-tool.zip) from https://www.tpc.org/tpc_documents_current_versions/current_specifications5.asp
and place in this directory.

Note that the TPC-DS generator no longer compiles on modern gcc versions so we need to use a Docker container.

## Build Image

```shell
docker build -t datafusion-benchmarks/tpcdsgen .
```

## Generate Data

Run the Docker container in interactive mode.

```shell
docker run -it -v `pwd`/data:/data datafusion-benchmarks/tpcdsgen
```

Use tpctools to generate the data

```shell
tpctools generate --benchmark tpcds \
  --scale 100 \
  --partitions 12 \
  --generator-path /DSGen-software-code-3.2.0rc1/tools \
  --output /data
```

Exit the container

```shell
exit
```

## Convert the CSV data to Parquet

Use tpcdsgen.py to convert the data

Paths are hard-coded in the script

Do not run in container

```shell
python3 tpcdsgen.py convert --scale-factor 100 --partitions 12
```