Class ImplementExceptAll

java.lang.Object
io.trino.sql.planner.iterative.rule.ImplementExceptAll
All Implemented Interfaces:
Rule<ExceptNode>

public class ImplementExceptAll extends Object implements Rule<ExceptNode>
Implement EXCEPT ALL using union, window and filter.

Transforms:

 - Except all
   output: a, b
     - Source1 (a1, b1)
     - Source2 (a2, b2)
     - Source3 (a3, b3)
 
Into:
 - Project (prune helper symbols)
   output: a, b
     - Filter (row_number invalid input: '<'= greatest(greatest(count1 - count2, 0) - count3, 0))
         - Window (partition by a, b)
           count1 invalid input: '<'- count(marker1)
           count2 invalid input: '<'- count(marker2)
           count3 invalid input: '<'- count(marker3)
           row_number invalid input: '<'- row_number()
               - Union
                 output: a, b, marker1, marker2, marker3
                   - Project (marker1 invalid input: '<'- true, marker2 invalid input: '<'- null, marker3 invalid input: '<'- null)
                       - Source1 (a1, b1)
                   - Project (marker1 invalid input: '<'- null, marker2 invalid input: '<'- true, marker3 invalid input: '<'- null)
                       - Source2 (a2, b2)
                   - Project (marker1 invalid input: '<'- null, marker2 invalid input: '<'- null, marker3 invalid input: '<'- true)
                       - Source3 (a3, b3)