Selecting all items in one table and join with another table, allowing nulls
you must use left join
instead of right join
The different joins
inner join
: keep only the rows where there's data in both table
left join
: keep all the rows of the left table and add what is possible from the right one
right join
: keep all the rows of the right table and add what is possible from the left one
The left table is always the table we already have and the right table is the one we are joining with.
For the record, there is also a cross join
which joins each row in the left table with each row in the right table, but this one isn't used very often.
I hope all this is now clearer for you :)
Corrected query
select bird_name, member_id
from birds
left join bird_likes on birds.bird_id = bird_likes.bird_id
where member_id = 2;
Be aware that this assumes that the column member_id
is in the bird table, otherwise you can keep the condition like this :
select bird_name, member_id
from birds
left join bird_likes on
birds.bird_id = bird_likes.bird_id and
bird_likes.member_id = 2;
SELECT bird_name, member_id
FROM birds
LEFT JOIN bird_likes ON birds.bird_id=bird_likes.bird_id AND member_id=2
You want to use left outer join
in this case
select bird_name, member_id
from birds
left outer join bird_likes on birds.bird_id = bird_likes.bird_id
where member_id = 2;
This will return all bird names and 'null' for ones with empty likes.