query
Calcite framework
core operators:
Scan Filter Project Join Sort Aggregate Union Values
Streaming operators:
Delta(converts relation to stream)
Chi(converts stream to relation)
In SQL, the STREAM keyword signifies Delta.
Streaming algebra
Filter Route Partition Round-robin Queue Aggregate Merge Stor Replay Sort Lookup
Optimizing streaming queries
優(yōu)化流查詢单旁，傳統(tǒng)數(shù)據(jù)庫理論中的關系轉(zhuǎn)化任然適用：條件下推碉纳、列裁剪斤斧、消除空輸入源俗慈。
