README.md

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# Apache DataSketches library functions for Google BigQuery 

[User-Defined Aggregate Functions (UDAFs)](https://cloud.google.com/bigquery/docs/user-defined-aggregates) and
[non-aggregate (scalar) functions (UDFs)](https://cloud.google.com/bigquery/docs/user-defined-functions) for BigQuery SQL engine.

Please visit the main 
[Apache DataSketches website](https://datasketches.apache.org) 
for more information about DataSketches library.

If you are interested in making contributions to this project please see our 
[Community](https://datasketches.apache.org/docs/Community/) 
page for how to contact us.

## Requirements

- Requires [Emscripten (emcc compiler)](https://emscripten.org/)
- Requires a link to **/datasketches-cpp** in this repository
- Requires make utility
- Requires [Google Cloud CLI](https://cloud.google.com/sdk/docs/install)


## Building, Installing, and Testing

- Requires setting environment variables 
    - GCS_BUCKET: to hold compiled artifacts
    - BQ_DATASET: location of stored SQL functions (routines)

```
make          # performs compilation
make install  # upload to $GCS_BUCKET & create functions in $BQ_DATASET
make test     # runs predefined tests in BQ
```

The above steps can be executed in the root directory to install everything, or can be run from an individual sketch directory to install only that particular sketch.

## Examples
For examples see test directories in individual sketch directories.