substrait.py

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from datafusion import SessionContext
from datafusion import substrait as ss


# Create a DataFusion context
ctx = SessionContext()

# Register table with context
ctx.register_csv(
    "aggregate_test_data", "./testing/data/csv/aggregate_test_100.csv"
)

substrait_plan = ss.substrait.serde.serialize_to_plan(
    "SELECT * FROM aggregate_test_data", ctx
)
# type(substrait_plan) -> <class 'datafusion.substrait.plan'>

# Encode it to bytes
substrait_bytes = substrait_plan.encode()
# type(substrait_bytes) -> <class 'bytes'>, at this point the bytes can be distributed to file, network, etc safely
# where they could subsequently be deserialized on the receiving end.

# Alternative serialization approaches
# type(substrait_bytes) -> <class 'bytes'>, at this point the bytes can be distributed to file, network, etc safely
# where they could subsequently be deserialized on the receiving end.
substrait_bytes = ss.substrait.serde.serialize_bytes(
    "SELECT * FROM aggregate_test_data", ctx
)

# Imagine here bytes would be read from network, file, etc ... for example brevity this is omitted and variable is simply reused
# type(substrait_plan) -> <class 'datafusion.substrait.plan'>
substrait_plan = ss.substrait.serde.deserialize_bytes(substrait_bytes)

# type(df_logical_plan) -> <class 'substrait.LogicalPlan'>
df_logical_plan = ss.substrait.consumer.from_substrait_plan(
    ctx, substrait_plan
)

# Back to Substrait Plan just for demonstration purposes
# type(substrait_plan) -> <class 'datafusion.substrait.plan'>
substrait_plan = ss.substrait.producer.to_substrait_plan(df_logical_plan)