MySQL 8.0

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select version();


version()


8.0.22


create table sampledata (
id int,
age int,
seeing int,
hearing int,
walking int,
PRIMARY KEY (id)
);

INSERT INTO `sampledata` VALUES (1,64,1,1,1),(2,63,2,2,1),(3,32,3,2,1),(4,39,4,2,1),(5,11,5,2,2),(6,3,NULL,NULL,NULL),(7,30,NULL,2,2),(8,7,2,2,2);

create table difficulty (
id int,
code int,
description varchar(50),
PRIMARY KEY (id)
);

INSERT INTO difficulty VALUES (1,1,'No, No Difficulty'),(2,2,'Yes, Some Difficulty'),(3,3,'Yes, A Lot of Difficulty'),(4,4,'Cannot do it at all');
select 
t3.category,
if(grouping(t3.description) ,
'Total', t3.description) as description,
sum(t4.count_) as count from 
( 
select c2.category, c1.description 
from (
select  description from difficulty union all select 'Valid Blank' 
union all select 'NOT VALID' 
union all select 'InValid Blank')c1 
cross join 
(
select 'seeing' as category 
union all select 'hearing' 
union all select 'walking') c2 
) 
t3

left join

(select 
t5.category,
t5.description,
count(*) as count_
from 
(select 
t2.category, 
case 
when t2.value is null and t2.age<5 then 'Valid Blank'
when t2.value is not null and t1.code is null  then 'NOT VALID'
when t1.code is null and t2.age>5 then 'InValid Blank'
else t1.description
end description
from difficulty t1 right join 
(
select 'seeing' as category, age, seeing as value from sampledata
union all
select 'hearing', age,hearing from sampledata
union all 
select 'walking', age,walking from sampledata
)t2 on t1.code=t2.value
) t5
group by t5.category,
t5.description
) t4
  on 
t3.category=t4.category and t3.description=t4.description

group by t3.category,
t3.description with rollup


category
description
count


hearing
Cannot do it at all
null

hearing
InValid Blank
null

hearing
No, No Difficulty
1

hearing
NOT VALID
null

hearing
Valid Blank
1

hearing
Yes, A Lot of Difficulty
null

hearing
Yes, Some Difficulty
6

hearing
Total
8

seeing
Cannot do it at all
1

seeing
InValid Blank
1

seeing
No, No Difficulty
1

seeing
NOT VALID
1

seeing
Valid Blank
1

seeing
Yes, A Lot of Difficulty
1

seeing
Yes, Some Difficulty
2

seeing
Total
8

walking
Cannot do it at all
null

walking
InValid Blank
null

walking
No, No Difficulty
4

walking
NOT VALID
null

walking
Valid Blank
1

walking
Yes, A Lot of Difficulty
null

walking
Yes, Some Difficulty
3

walking
Total
8

null
Total
24

category	description	count
hearing	Cannot do it at all	null
hearing	InValid Blank	null
hearing	No, No Difficulty	1
hearing	NOT VALID	null
hearing	Valid Blank	1
hearing	Yes, A Lot of Difficulty	null
hearing	Yes, Some Difficulty	6
hearing	Total	8
seeing	Cannot do it at all	1
seeing	InValid Blank	1
seeing	No, No Difficulty	1
seeing	NOT VALID	1
seeing	Valid Blank	1
seeing	Yes, A Lot of Difficulty	1
seeing	Yes, Some Difficulty	2
seeing	Total	8
walking	Cannot do it at all	null
walking	InValid Blank	null
walking	No, No Difficulty	4
walking	NOT VALID	null
walking	Valid Blank	1
walking	Yes, A Lot of Difficulty	null
walking	Yes, Some Difficulty	3
walking	Total	8
null	Total	24