create temporary table t1(id int);
create temporary table t2(id int, num int);

insert into t1 values ( 1 );
insert into t1 values ( 2 );
insert into t1 values ( 3 );
insert into t1 values ( 4 );
insert into t1 values ( 5 );
insert into t1 values ( 6 );
insert into t1 values ( 7 );
insert into t1 values ( 8 );

insert into t2 values ( 1 , 0 );
insert into t2 values ( 3 , 0 );
insert into t2 values ( 5 , 0 );
insert into t2 values ( 2 , 3 );
insert into t2 values ( 4 , 3 );

select * from t1;
+ ------+
 
| id   |
+ ------+
 
|     1  |
|     2  |
|     3  |
|     4  |
|     5  |
+ ------+
 

select * from t2;
+ ------+------+
 
| id   | num  |
+ ------+------+
 
|     1  |     0  |
|     3  |     0  |
|     5  |     0  |
|     2  |     3  |
|     4  |     3  |
+ ------+------+
 

select t2.id as id2, t2.num, t1.id as id1
from
t1 left join t2 on t1.id=t2.id
where
t2.id is null or (t2.num<> 3 );
+ ------+------+------+
 
| id2  | num  | id1  |
+ ------+------+------+
 
|     1  |     0  |     1  |
|     3  |     0  |     3  |
|     5  |     0  |     5  |
| NULL | NULL |     6  |
| NULL | NULL |     7  |
| NULL | NULL |     8  |
+ ------+------+------+