SQL split values to multiple rows

Question

I have table :

id | name    
1  | a,b,c    
2  | b

i want output like this :

id | name    
1  | a    
1  | b    
1  | c             


        

Answer 1

If you can create a numbers table, that contains numbers from 1 to the maximum fields to split, you could use a solution like this:

select
  tablename.id,
  SUBSTRING_INDEX(SUBSTRING_INDEX(tablename.name, ',', numbers.n), ',', -1) name
from
  numbers inner join tablename
  on CHAR_LENGTH(tablename.name)
     -CHAR_LENGTH(REPLACE(tablename.name, ',', ''))>=numbers.n-1
order by
  id, n

Please see fiddle here.

If you cannot create a table, then a solution can be this:

select
  tablename.id,
  SUBSTRING_INDEX(SUBSTRING_INDEX(tablename.name, ',', numbers.n), ',', -1) name
from
  (select 1 n union all
   select 2 union all select 3 union all
   select 4 union all select 5) numbers INNER JOIN tablename
  on CHAR_LENGTH(tablename.name)
     -CHAR_LENGTH(REPLACE(tablename.name, ',', ''))>=numbers.n-1
order by
  id, n

an example fiddle is here.