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A handle to a query that is executing continuously in the background as new data arrives. All methods are thread-safe.
Syntax
# Returned by DataStreamWriter.start() or DataStreamWriter.toTable()
q = df.writeStream.format("console").start()
Properties
| Property | Description |
|---|---|
id |
Returns the unique ID of this query that persists across restarts from checkpoint data. |
runId |
Returns the unique ID of this query that does not persist across restarts. |
name |
Returns the user-specified name of the query, or None if not specified. |
isActive |
Returns whether this streaming query is currently active. |
status |
Returns the current status of the query as a dict. |
recentProgress |
Returns an array of the most recent StreamingQueryProgress updates for this query. |
lastProgress |
Returns the most recent StreamingQueryProgress update, or None if there have been no updates. |
Methods
| Method | Description |
|---|---|
awaitTermination(timeout) |
Waits for the termination of this query, either by stop() or by an exception. |
processAllAvailable() |
Blocks until all available data in the source has been processed and committed to the sink. Intended for testing. |
stop() |
Stops this streaming query. |
explain(extended) |
Prints the (logical and physical) plans to the console for debugging. |
exception() |
Returns the StreamingQueryException if the query terminated with an exception, or None. |
Examples
sdf = spark.readStream.format("rate").load()
sq = sdf.writeStream.format('memory').queryName('this_query').start()
sq.isActive
# True
sq.name
# 'this_query'
sq.awaitTermination(5)
# False
sq.stop()
sq.isActive
# False