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sqlnullcoalesce

SQL how to find non null column?

I have a table with lots of columns, say I have columns

A, B, C, D

in each of these columns, only one column in any one record will be filled and the others will always be NULL.

I need a select statement that will return the Column of the non null Column.

I've tried coalesce, but this return a value, not the column to which the value belongs to.

Anyone know the simplest way to do this?

Solution 
  • SELECT
    CASE
        WHEN A IS NOT NULL THEN 'A'
        WHEN B IS NOT NULL THEN 'B'
        WHEN C IS NOT NULL THEN 'C'
        WHEN D IS NOT NULL THEN 'D'
    END
FROM
    MyTable