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create table myTable (
Column1 int ,
Column2 int ) ;
insert into myTable values
(10,Null),
(9,15);
Records: 2 Duplicates: 0 Warnings: 0
select * from myTable;
| Column1 | Column2 |
|---|---|
| 10 | null |
| 9 | 15 |
SELECT
CASE
WHEN Column1 IS null THEN Column2
WHEN Column2 IS null THEN Column1
ELSE (Column1+Column2) / 2
END as column3
FROM myTable
| column3 |
|---|
| 10 |
| 12.0000 |