hyparquet-writer/README.md

# Hyparquet Writer

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## Usage

Call `parquetWrite` with a list of columns, each column is an object with a `name` and `data` field. The `data` field should be an array of same-type values.

```javascript
import { parquetWrite } from 'hyparquet-writer'

const arrayBuffer = parquetWrite({
  columnData: [
    { name: 'name', data: ['Alice', 'Bob', 'Charlie'], type: 'STRING' },
    { name: 'age', data: [25, 30, 35], type: 'INT32' },
  ],
})
```

## References

 - https://github.com/hyparam/hyparquet
 - https://github.com/hyparam/hyparquet-compressors
 - https://github.com/apache/parquet-format
 - https://github.com/apache/parquet-testing
Plain string support 2025-03-26 03:15:14 +00:00			`# Hyparquet Writer`

Snappy compression 2025-03-27 06:37:05 +00:00			`[![npm](https://img.shields.io/npm/v/hyparquet-writer)](https://www.npmjs.com/package/hyparquet-writer)`
Optional compression flag 2025-03-27 07:27:22 +00:00			`[![minzipped](https://img.shields.io/bundlephobia/minzip/hyparquet-writer)](https://www.npmjs.com/package/hyparquet-writer)`
Handle byte array vs string, and change parquetWrite column api 2025-03-26 07:45:22 +00:00			`[![workflow status](https://github.com/hyparam/hyparquet-writer/actions/workflows/ci.yml/badge.svg)](https://github.com/hyparam/hyparquet-writer/actions)`
Plain string support 2025-03-26 03:15:14 +00:00			`[![mit license](https://img.shields.io/badge/License-MIT-orange.svg)](https://opensource.org/licenses/MIT)`
Option for key_value_metadata 2025-03-31 20:42:57 +00:00			`![coverage](https://img.shields.io/badge/Coverage-96-darkred)`
Use constants from hyparquet 2025-04-01 06:32:14 +00:00			`[![dependencies](https://img.shields.io/badge/Dependencies-1-blueviolet)](https://www.npmjs.com/package/hyparquet-writer?activeTab=dependencies)`
Support nullable columns 2025-03-26 05:36:06 +00:00
			`## Usage`

Handle byte array vs string, and change parquetWrite column api 2025-03-26 07:45:22 +00:00			Call `parquetWrite` with a list of columns, each column is an object with a `name` and `data` field. The `data` field should be an array of same-type values.

Support nullable columns 2025-03-26 05:36:06 +00:00			```javascript
Handle byte array vs string, and change parquetWrite column api 2025-03-26 07:45:22 +00:00			`import { parquetWrite } from 'hyparquet-writer'`
Support nullable columns 2025-03-26 05:36:06 +00:00
Optional compression flag 2025-03-27 07:27:22 +00:00			`const arrayBuffer = parquetWrite({`
			`columnData: [`
Allow specifying column type 2025-03-28 23:13:27 +00:00			`{ name: 'name', data: ['Alice', 'Bob', 'Charlie'], type: 'STRING' },`
			`{ name: 'age', data: [25, 30, 35], type: 'INT32' },`
Optional compression flag 2025-03-27 07:27:22 +00:00			`],`
			`})`
Support nullable columns 2025-03-26 05:36:06 +00:00			```

			`## References`

			`- https://github.com/hyparam/hyparquet`
Publish v0.1.4 2025-03-31 21:51:11 +00:00			`- https://github.com/hyparam/hyparquet-compressors`
Support nullable columns 2025-03-26 05:36:06 +00:00			`- https://github.com/apache/parquet-format`
			`- https://github.com/apache/parquet-testing`