Table column to row mysql query - mysql

Question

I have 2 tables i need the result table almost converted from column to row converted
Table 1 : master_table
master_id user_name
1 name1
2 name2
3 name3
4 name4
Table 2 : master_meta_table
id master_id meta_key meta_value
1 1 f_name fname1
2 2 f_name fname2
3 2 l_name lname2
4 2 age age2
5 3 l_name lnam3
6 3 age age3
7 4 sex male
I would like to get the result like this
master_id user_name f_name l_name age sex
1 name1 fname1
2 name2 fname2 lname2 age2
3 name3 lname3 age3
4 name4 fname4 male
Please some one help me with this...

Answer 1

Try:
select
mt1.master_id,
mt1.user_name,
max(case when mt2.meta_key = 'f_name' then mt2.meta_value end) as fname,
max(case when mt2.meta_key = 'l_name' then mt2.meta_value end) as lname,
max(case when mt2.meta_key = 'age' then mt2.meta_value end) as age,
max(case when mt2.meta_key = 'sex' then mt2.meta_value end) as sex
from
master_table mt1
join master_meta_table mt2 on mt1.master_id = mt2.master_id
group by
mt1.master_id,
mt1.user_name
Fiddle: http://sqlfiddle.com/#!2/af277e/3/0

Answer 2

Here is your DDL
create table master_table
(
master_id int,
user_name varchar(20)
);
create table master_meta_table
(
id int,
master_id int,
meta_key varchar(20),
meta_value varchar(20)
);
insert into master_table
values (
1,'name1');
insert into master_table
values (
2,'name2');
insert into master_table
values (
3,'name3');
insert into master_table
values (
4,'name4');
insert into master_meta_table
values (
1,1,'f_name','fname1');
insert into master_meta_table
values (
2,2,'f_name','fname2');
insert into master_meta_table
values (
3,2,'l_name','lname2');
insert into master_meta_table
values (
4,2,'age','age2');
insert into master_meta_table
values (
5,3,'l_name','lname3');
insert into master_meta_table
values (
6,3,'age','age3');
insert into master_meta_table
values (
7,4,'sex','male');
your query
select
mt.master_id,
mt.user_name,
max (case when mmt.meta_key = 'f_name' then mmt.meta_value end) as fname,
max (case when mmt.meta_key = 'l_name' then mmt.meta_value end) as lname,
max (case when mmt.meta_key = 'age' then mmt.meta_value end) as age,
max (case when mmt.meta_key = 'sex' then mmt.meta_value end) as sex
from
master_table mt,master_meta_table mmt
where mt.master_id = mmt.master_id
group by mt.master_id,mt.user_name
http://sqlfiddle.com/#!4/55845/8