Literal
Describes the literal relation operator in the multi-stage query engine.
The literal operator is used to define a constant value in the query. This operator may be generated by the multi-stage query engine when you use a constant value in a query.
Blocking nature
The literal operator is a blocking operator, but given its trivial nature it should not matter.
Implementation details
The literal operator is a simple operator that does not require any computation.
Hints
None
Stats
executionTimeMs
Type: Long
The summation of time spent by all threads executing the operator. This means that the wall time spent in the operation may be smaller that this value if the parallelism is larger than 1.
emittedRows
Type: Long
The number of groups emitted by the operator. It should always be one.
Explain attributes
None
Tips and tricks
Avoid very large literals
Take care when using very large literals (in the order hundreds of KBs), as they may need to be sent from brokers to servers and in general may introduce latencies in the parsing and query optimization.