Parsed test spec with 2 sessions

starting permutation: s1prep s2text s1member s1end
step s1prep: BEGIN;
		  PREPARE member AS SELECT grp, sum((m ->> 'a')::float8) AS s FROM iso_vl GROUP BY grp ORDER BY grp;
		  PREPARE len AS SELECT grp, sum(jsonb_array_length(doc -> 'l')) AS s FROM iso_vl GROUP BY grp ORDER BY grp;
		  EXPLAIN (COSTS OFF) EXECUTE member;
		  EXPLAIN (COSTS OFF) EXECUTE len;
QUERY PLAN                   
-----------------------------
Custom Scan (SiftAgg)        
  Index: iso_vl_col          
  Group Keys: grp            
  Pushed Aggregates: sum(m.a)
(4 rows)

QUERY PLAN                                         
---------------------------------------------------
Custom Scan (SiftAgg)                              
  Index: iso_vl_col                                
  Group Keys: grp                                  
  Pushed Aggregates: sum(jsonb_array_length(doc.l))
(4 rows)

step s2text: INSERT INTO iso_vl VALUES (100001, 0, jsonb_build_object('a', 'x'), jsonb_build_object('l', jsonb_build_array(1)));
step s1member: EXECUTE member;
ERROR:  sift: a column of the aggregate scan holds values its index cannot store
step s1end: ROLLBACK; DEALLOCATE ALL;

starting permutation: s1prep s2scalar s1len s1end
step s1prep: BEGIN;
		  PREPARE member AS SELECT grp, sum((m ->> 'a')::float8) AS s FROM iso_vl GROUP BY grp ORDER BY grp;
		  PREPARE len AS SELECT grp, sum(jsonb_array_length(doc -> 'l')) AS s FROM iso_vl GROUP BY grp ORDER BY grp;
		  EXPLAIN (COSTS OFF) EXECUTE member;
		  EXPLAIN (COSTS OFF) EXECUTE len;
QUERY PLAN                   
-----------------------------
Custom Scan (SiftAgg)        
  Index: iso_vl_col          
  Group Keys: grp            
  Pushed Aggregates: sum(m.a)
(4 rows)

QUERY PLAN                                         
---------------------------------------------------
Custom Scan (SiftAgg)                              
  Index: iso_vl_col                                
  Group Keys: grp                                  
  Pushed Aggregates: sum(jsonb_array_length(doc.l))
(4 rows)

step s2scalar: INSERT INTO iso_vl VALUES (100002, 0, jsonb_build_object('a', 1), jsonb_build_object('l', 'x'));
step s1len: EXECUTE len;
ERROR:  sift: a column of the aggregate scan holds values its index cannot store
step s1end: ROLLBACK; DEALLOCATE ALL;

starting permutation: s1prep s2num s1member s1rollback s1again s1drop
step s1prep: BEGIN;
		  PREPARE member AS SELECT grp, sum((m ->> 'a')::float8) AS s FROM iso_vl GROUP BY grp ORDER BY grp;
		  PREPARE len AS SELECT grp, sum(jsonb_array_length(doc -> 'l')) AS s FROM iso_vl GROUP BY grp ORDER BY grp;
		  EXPLAIN (COSTS OFF) EXECUTE member;
		  EXPLAIN (COSTS OFF) EXECUTE len;
QUERY PLAN                   
-----------------------------
Custom Scan (SiftAgg)        
  Index: iso_vl_col          
  Group Keys: grp            
  Pushed Aggregates: sum(m.a)
(4 rows)

QUERY PLAN                                         
---------------------------------------------------
Custom Scan (SiftAgg)                              
  Index: iso_vl_col                                
  Group Keys: grp                                  
  Pushed Aggregates: sum(jsonb_array_length(doc.l))
(4 rows)

step s2num: INSERT INTO iso_vl VALUES (100003, 0, jsonb_build_object('a', '7'), jsonb_build_object('l', jsonb_build_array(1)));
step s1member: EXECUTE member;
ERROR:  sift: a column of the aggregate scan holds values its index cannot store
step s1rollback: ROLLBACK;
step s1again: EXECUTE member; EXPLAIN (COSTS OFF) EXECUTE member;
grp|   s
---+----
  0|3010
  1|3000
  2|2997
(3 rows)

QUERY PLAN                    
------------------------------
GroupAggregate                
  Group Key: grp              
  ->  Sort                    
        Sort Key: grp         
        ->  Seq Scan on iso_vl
(5 rows)

step s1drop: DEALLOCATE ALL;

starting permutation: s1prep s2begin s2text s1member s2abort s1member s1end
step s1prep: BEGIN;
		  PREPARE member AS SELECT grp, sum((m ->> 'a')::float8) AS s FROM iso_vl GROUP BY grp ORDER BY grp;
		  PREPARE len AS SELECT grp, sum(jsonb_array_length(doc -> 'l')) AS s FROM iso_vl GROUP BY grp ORDER BY grp;
		  EXPLAIN (COSTS OFF) EXECUTE member;
		  EXPLAIN (COSTS OFF) EXECUTE len;
QUERY PLAN                   
-----------------------------
Custom Scan (SiftAgg)        
  Index: iso_vl_col          
  Group Keys: grp            
  Pushed Aggregates: sum(m.a)
(4 rows)

QUERY PLAN                                         
---------------------------------------------------
Custom Scan (SiftAgg)                              
  Index: iso_vl_col                                
  Group Keys: grp                                  
  Pushed Aggregates: sum(jsonb_array_length(doc.l))
(4 rows)

step s2begin: BEGIN;
step s2text: INSERT INTO iso_vl VALUES (100001, 0, jsonb_build_object('a', 'x'), jsonb_build_object('l', jsonb_build_array(1)));
step s1member: EXECUTE member;
grp|   s
---+----
  0|3003
  1|3000
  2|2997
(3 rows)

step s2abort: ROLLBACK;
step s1member: EXECUTE member;
grp|   s
---+----
  0|3003
  1|3000
  2|2997
(3 rows)

step s1end: ROLLBACK; DEALLOCATE ALL;