-
Type:
Sub-task
-
Status: Resolved
-
Priority:
Major
-
Resolution: Invalid
-
Affects Version/s: None
-
Fix Version/s: None
-
Component/s: None
-
Labels:None
This patch introduces CBO step in SemanticAnalyzer. For now the CostBasedOptimizer is an empty shell.
The contract between SemAly and CBO is:
- CBO step is controlled by the 'hive.enable.cbo.flag'.
- When true Hive SemAly will hand CBO a Hive Operator tree (with operators annotated with stats). If it can CBO will return a better plan in Hive AST form.