duckdb data accelerator.md

DuckDB Data Accelerator

To use DuckDB as Data Accelerator, specify duckdb as the engine for acceleration.

datasets:
  - from: spice.ai:path.to.my_dataset
    name: my_dataset
    acceleration:
      engine: duckdb

Configuration

Spice.ai currently only supports mode: memory for DuckDB accelerator.

Configuration params are provided in the acceleration section for a data store. Other common acceleration fields can be configured for DuckDB, see see datasets.

{% hint style="warning" %} LIMITATIONS

The DuckDB accelerator does not support nested lists, or structs with nested structs/lists field types. For example:
- Supported:
  - SELECT {'x': 1, 'y': 2, 'z': 3}
- Unsupported:
  - SELECT [['duck', 'goose', 'heron'], ['frog', 'toad']]
  - SELECT {'x': [1, 2, 3]}
The DuckDB accelerator does not support enum, dictionary, or map field types. For example:
- Unsupported:
  - SELECT MAP(['key1', 'key2', 'key3'], [10, 20, 30])
The DuckDB accelerator does not support Decimal256 (76 digits), as it exceeds DuckDB's maximum Decimal width of 38 digits.
Updating a dataset with DuckDB acceleration while the Spice Runtime is running (hot-reload) will cause the DuckDB accelerator query federation to disable until the Runtime is restarted. {% endhint %}

{% hint style="warning" %} MEMORY CONSIDERATIONS

When accelerating a dataset using mode: memory (the default), some or all of the dataset is loaded into memory. Ensure sufficient memory is available, including overhead for queries and the runtime, especially with concurrent queries. {% endhint %}