select - MySQL - How to display row value as column name using concat and group_concat

Question

Table 1:

id   | typeid | available|
0    | 1      | 12       |
0    | 2      | 44       |

Table 2:

typeid   | typename   |
1        | CL          |
2        | ML          |

I have a query using concat and group_concat:

select id,concat(group_concat(typename,available)) as types from table1
join table2 on table2.typeid=table1.typeid

I got the result as:

id | types   | 
0  | CL12,ML44 |

But I want to display it like this:

id   | CL   | ML    |
0    | 12   | 44    |

Is there any way to split the group_concat result to columns heads?

I want dynamically fetch data from table2. Some user can add data to table2. So hard-coding typename is not possible.

Answer 1

You should use table pivoting. There is no PIVOT command in MySQL, so you can use this query -

SELECT
  t1.id,
  MAX(IF(t2.typename = 'CL', t1.available, NULL)) AS CL,
  MAX(IF(t2.typename = 'ML', t1.available, NULL)) AS ML
FROM table1 t1
  JOIN table2 t2
    ON t1.typeid = t2.typeid
GROUP BY
  t1.id;

MySQL pivot tables (transform rows to columns).

Use GROUP_CONCAT function instead of MAX, if multiple available values are possible.