ASTNode getOptimizedAST() throws SemanticException {
    return getOptimizedAST(logicalPlan());
  }
Get Optimized AST for the given QB tree in the semAnalyzer.

@return Optimized operator tree translated in to Hive AST
@throws SemanticException
ql/src/java/org/apache/hadoop/hive/ql/parse/CalcitePlanner.java