php - MYSQL | Request from two tables 2 -

i have 2 mysql tables:

a (users table):

id username room

1    user1    1  2    user2    1 3    user3    1

b (blocked users):

id   username 1    user3

my request here (i user1 , user2 user3 in block):

select a.id, a.username `table1` a, `table2` b    a.roomid = 1 , a.username != b.username

but wrong request. thanks!

you need either join 2 tables a&b like

select a.id, a.username `table1` join `table2` b on `table1`.id = `table2`.id a.room = 1 , a.username != b.username

or column name room not roomid like

select a.id, a.username `table1` a, `table2` b  a.room = 1 , a.username != b.username

Error