Postgres 14

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CREATE TABLE marginality_by_channel (dist_chann_name int, year int, operative_margin int);
INSERT INTO marginality_by_channel VALUES
    ('1', '2020', '20783'),
    ('1', '2021', '5791'),
    ('2', '2020', '30362'),
    ('3', '2021', '14501'),
    ('3', '2020', '2765'),
    ('3', '2021', '4535');
6 rows affected

SELECT *
FROM  crosstab(
   $$
   SELECT dist_chann_name, year, operative_margin
   FROM   marginality_by_channel
   ORDER  BY 1, 2
   $$
 , 'VALUES (2020), (2021)'
   ) AS ct ("DC" int, "2020" int, "2021" int);


DC
2020
2021


1
20783
5791

2
30362
null

3
2765
4535


-- This works, too, with the 2-parameter form:
SELECT *
FROM  crosstab(
   $$
   SELECT dist_chann_name::text, year, operative_margin::text
   FROM   marginality_by_channel
   ORDER  BY 1, 2
   $$
 , 'VALUES (2020), (2021)'
   ) AS ct ("DC" int, "2020" int, "2021" int);


DC
2020
2021


1
20783
5791

2
30362
null

3
2765
4535


-- But not with the 1-parameter form:
SELECT *
FROM  crosstab(
   $$
   SELECT dist_chann_name::text, year, operative_margin
   FROM   marginality_by_channel
   ORDER  BY 1, 2
   $$
   ) AS ct ("DC" int, "2020" int, "2021" int);
ERROR:  invalid return type
DETAIL:  SQL rowid datatype does not match return rowid datatype.


-- And this raises your error exactly:
SELECT *
FROM  crosstab(
   $$
   SELECT dist_chann_name, year, operative_margin::text  -- !
   FROM   marginality_by_channel
   ORDER  BY 1, 2
   $$
   ) AS ct ("DC" int, "2020" int, "2021" int);
ERROR:  return and sql tuple descriptions are incompatible