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StreamingRelationV2 Leaf Logical Operator¶

StreamingRelationV2 is a leaf logical operator that represents SupportsRead streaming tables (with MICRO_BATCH_READ or CONTINUOUS_READ capabilities) in a logical plan of a streaming query.

Tip

Learn more about Leaf Logical Operators, SupportsRead and Table Capabilities in The Internals of Spark SQL online book.

Creating Instance¶

StreamingRelationV2 takes the following to be created:

TableProvider (Spark SQL)
Source Name
Table (Spark SQL)
Extra Options
Output Attributes (Spark SQL)
StreamingRelation
SparkSession (Spark SQL)

StreamingRelationV2 is created when:

DataStreamReader is reqested to load data (for a SupportsRead table with MICRO_BATCH_READ or CONTINUOUS_READ capabilities)
MemoryStreamBase is requested for a logical query plan

Logical Resolution¶

StreamingRelationV2 is resolved to the following leaf logical operators:

StreamingDataSourceV2Relation or StreamingExecutionRelation when MicroBatchExecution stream execution engine is requested for an analyzed logical plan
StreamingDataSourceV2Relation when ContinuousExecution stream execution engine is created (and initializes an analyzed logical plan)