WriteToStream Logical Operator¶

WriteToStream is a unary logical operator (Spark SQL) that represents WriteToStreamStatement operator at execution time (of a streaming query).

WriteToStream is used to create the stream execution engines:

• MicroBatchExecution
• ContinuousExecution

Creating Instance¶

WriteToStream takes the following to be created:

• Name
• Checkpoint Location
• Sink Table (Spark SQL)
• OutputMode
• deleteCheckpointOnStop flag
• LogicalPlan (Spark SQL) of the Input Query
• Optional TableCatalog and Identifier (default: undefined)

WriteToStream is created when:

• ResolveWriteToStream logical resolution rule is executed (to resolve WriteToStreamStatement operators)

isStreaming¶

isStreaming: Boolean

isStreaming is part of the LogicalPlan (Spark SQL) abstraction.

isStreaming is true.

Output Schema¶

output: Seq[Attribute]

output is part of the QueryPlan (Spark SQL) abstraction.

output is empty (Nil)