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README updates!
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README.md

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@@ -20,8 +20,8 @@ import xarray_sql as qr
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ds = xr.tutorial.open_dataset('air_temperature')
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# The same as a dask-sql Context; i.e. an Apache DataFusion Context.
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c = qr.Context(ds)
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c.create_table('air', ds, chunks=dict(time=24))
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c = qr.XarrayContext(ds)
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c.from_dataset('air', ds, chunks=dict(time=24))
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df = c.sql('''
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SELECT
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''')
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# A table of the average temperature for each location across time.
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df.compute()
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df.to_pandas()
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# Alternatively, you can just create the DataFrame from the Dataset:
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df = qr.read_xarray(ds)
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df = qr.read_xarray(ds).to_pandas()
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df.head()
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```
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`from_map()` and `to_dataframe()`. For SQL support, we just use `dask-sql`.
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That's it!
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_2025 update_: This library now implements a dask-like `from_map` interface in
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pure `datafusion` and `pyarrow`, but works with the same principle!
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## Why does this work?
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Underneath Xarray, Dask, and Pandas, there are NumPy arrays. These are paged in
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## What are the current limitations?
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Dask doesn't support
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`MultiIndex`s ([dask/dask#1493](https://github.com/dask/dask/issues/1493)). If
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it did, I suspect performance for many types of queries would greatly improve.
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Further, while this does play well with `dask-geopandas` (for geospatial query
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support), certain types of operations don't quite match standard geopandas.
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Spatial joins come to mind as a killer feature, but only inner joins are
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supported ([geopandas/dask-geopandas#72](https://github.com/geopandas/dask-geopandas/issues/72))
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.
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_2025 update_: TBD, `datafusion` provides a whole new world!
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## What would a deeper integration look like?
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