Question

Here is my table emp :

+---------+------------------+
| emp     |  id      | color |
+---------+------------------+
| hary    | 123      |  red  |
+---------+------------------+
| lary    | 125      | green |
+---------+------------------+
| gary    | 038      |  red  |
+---------+------------------+
| Kris    | 912      | blue  |
+---------+------------------+
| hary    | 123      |  red  |
+---------+------------------+
| Ronn    | 334      | green |
+---------+------------------+

Now I want to find out the count of each colour i.e red,green and blue;

On this context I’m trying to write down the query in terms of where color like '%bl%',like '%ree%',like %ed%. and to want this result

+--------------------------+
| red | blue | green       |
+--------------------------+
|   3 |   1  |  2          | 
+--------------------------+

I have tried this thing:

    select count(case when color='green' then 1 end) as Green,count(case when 
color='blue' then 1 end) as Blue,count(case when color='Red' then 1 end) as Red from emp;

I don’t want to hardcode their name(as I’ll use it in my code jdbc).
I’ll appreciate any input’s regarding this questain.

Answer 1

select color,count(*) clrCount
from emp 
group by color

with where clause

select color,count(*) clrCount
from emp where (color like '%bl%' or color like '%ree%')
group by color