如何在MySQL中将行合并为具有相同列值的行

Question

I have a table like this:

id  value  
1   a   
1   b   
2   c   
2   d   
2   e   

I want to combine rows with the same ids into one,here is what i want as result:

id  value  
1   a b 
2   c d e   

Answer 1

try this

select id,group_concat(value) as value from tb_name group by id;

if you want space instead ',' then try below query

select id,replace(group_concat(value), ',' ,' ') as value from tb_name group by id;