formato (DataStreamWriter)

Specifica l'origine dati di output sottostante.

Sintassi

format(source)

Parametri

Restituzioni

DataStreamWriter

Examples

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

Scrivere un flusso di origine rate in 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()