EXPERT RESPONSE
You are likely referring to the recent question
Counting a row's NULL columns. (Note: that title is a bit misleading.
It should actually have been Counting a row's NOT NULL columns.)
If your table is similar to the sample table in that question, then the
answer is the same: you shouldn't need to write that horrendous series of CASE
expressions for each column. Normalize the table, so that you have a single column
with multiple rows, instead of multiple columns in one row.
Then the counting becomes trivial:
select count(columnx) as not_null_columns
from TableB
where id = 937
Notice that this gives the non-NULL count (it's the same query from the
previous question). The trick for counting NULL values—if you can call
it a trick—is that the normalized table would typically not
have a row for a NULL, i.e. a value that isn't there!
In the unnormalized table, you can count the number of NULLs using a similarly
horrendous series of CASE expressions, with IS NULL instead of IS NOT NULL.
In the normalized table, there are no NULLs at all, so there is nothing to count!
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