MySQL 5.5

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CREATE TABLE table_1 (
  `category` VARCHAR(2),
  `user_id` INT(2), 
  `value` DECIMAL(3,2)
 );
INSERT INTO table_1
(`category`, `user_id`, `value`)
VALUES
('A', 1, 0.01),
('A', 2, 0.05),
('A', 3, 0.09),
('A', 4, 0.12),
('B', 1, 0.34),
('B', 2, 0.27),
('B', 3, 0.08),
('B', 4, 0.12)
;
 CREATE TABLE table_2 (
  `category` VARCHAR(2),
  `user_id_type` VARCHAR(4), 
  `value` DECIMAL(3,2)
 );
select category, 
case when user_id % 2 = 0 then 'even' else 'odd' end user_id_type, 
sum(value) from table_1 group by user_id_type, category ORDER BY category;


category
user_id_type
sum(value)


A
odd
0.10

A
even
0.17

B
odd
0.42

B
even
0.39


select * from table_2;
insert into table_2
select category, 
case when user_id % 2 = 0 then 'even' else 'odd' end user_id_type, 
sum(value) from table_1 group by user_id_type, category ORDER BY category;
select * from table_2;


category
user_id_type
value


A
odd
0.10

A
even
0.17

B
odd
0.42

B
even
0.39