python/examples/readme_standalone.py

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# to you under the Apache License, Version 2.0 (the
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#
#   http://www.apache.org/licenses/LICENSE-2.0
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# under the License.

# %%

from ballista import BallistaBuilder
from datafusion.context import SessionContext

ctx: SessionContext = (
    BallistaBuilder()
    .config("ballista.job.name", "Readme Example")
    .config("datafusion.execution.target_partitions", "4")
    .standalone()
)

ctx.sql("create external table t stored as parquet location '../testdata/test.parquet'")

# %%
df = ctx.sql("select * from t limit 5")
pyarrow_batches = df.collect()
pyarrow_batches[0].to_pandas()
# %%
df = ctx.read_parquet("../testdata/test.parquet").limit(5)
pyarrow_batches = df.collect()
pyarrow_batches[0].to_pandas()
# %%