format (DataStreamWriter)

Anger den underliggande utdatakällan.

Syntax

format(source)

Parameters

Retur

DataStreamWriter

Exempel

df = spark.readStream.format("rate").load()
df.writeStream.format("text")
# <...streaming.readwriter.DataStreamWriter object ...>

Skriva en frekvenskällaström till CSV:

import tempfile
import time
with tempfile.TemporaryDirectory(prefix="format1") as d:
    with tempfile.TemporaryDirectory(prefix="format2") as cp:
        df = spark.readStream.format("rate").load()
        q = df.writeStream.format("csv").option("checkpointLocation", cp).start(d)
        time.sleep(5)
        q.stop()
        spark.read.schema("timestamp TIMESTAMP, value STRING").csv(d).show()