expect column not null values to be equal to

I want to compare the not null values in column of one table with the count of values in another table.
How can we do this ??
tab1:
c1 c2 c3
111 abc 21
222 abc 31
333 abc 41
null abc 51
444 def null
555 ghi 61

tab2:
c1 c2 c3 c4
324 aaa 1 null
24234 bbb 2 g
212 ccc null r
454 ddd 4 x
232 eee 5 null
454 fff null sd
212 ggf 8 csd

Now here, in this case I want to compare the counts of tab1 c1 (not null) and tab2 c2 .... If the count are same then success otherwise False