I am working on a query that is fairly similar the following:
CREATE TABLE #test (a char(1), b char(1)) INSERT INTO #test(a,b) VALUES ('A',NULL), ('A','B'), ('B',NULL), ('B',NULL) SELECT DISTINCT a,b FROM #test DROP TABLE #test
The result is, unsurprisingly,
a b ------- A NULL A B B NULL
The output I would like to see in actuality is:
a b ------- A B B NULL
That is, if a column has a value in some records but not in others, I want to throw out the row with NULL for that column. However, if a column has a NULL value for all records, I want to preserve that NULL.
What's the simplest/most elegant way to do this in a single query?
I have a feeling that this would be simple if I weren't exhausted on a Friday afternoon.