I have two tables, in which table 1 contains 4 columns while table 2 contains 8 columns. I have two columns in table1 that I want to compare them with two columns in table2.
NOT EXISTS
is a "null safe" version of NOT IN
.
If you mean the combination column1 AND column2 not in same row in table2:
select *
from table1
where NOT EXISTS (select 1 from table2
where table1.column1 = table2.column6
and table1.column2 = table2.column7)
Or if you mean just column1 and column2 values can't even be in different rows in table2:
select *
from table1
where NOT EXISTS (select 1 from table2
where table1.column1 = table2.column6)
and NOT EXISTS (select 1 from table2
where table1.column2 = table2.column7)