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CREATE TABLE YourTable (
"Id" INTEGER,
"QuestionId" VARCHAR(14)
);
INSERT INTO YourTable
("Id", "QuestionId")
VALUES
('1', 'MyQuestionId'),
('1', NULL),
('2', NULL),
('2', NULL);
4 rows affected
SELECT * FROM YourTable;
| Id | QuestionId |
|---|---|
| 1 | MyQuestionId |
| 1 | null |
| 2 | null |
| 2 | null |
WITH cte AS (
SELECT *,
CountNonNulls = COUNT(t.QuestionId) OVER (PARTITION BY t.Id)
FROM YourTable t
)
DELETE cte
WHERE CountNonNulls = 0;
Warning: Null value is eliminated by an aggregate or other SET operation.
2 rows affected
SELECT * FROM YourTable;
| Id | QuestionId |
|---|---|
| 1 | MyQuestionId |
| 1 | null |