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I am trying to return Col1 as a value for a list, IF Col2 = NULL

I am trying to return all Col1 values IF the respective Col2 value = NULL I have thought of IF Col2 = NULL Return Col2 END IF, But I am unsure of how to format this, because when I run it I get errors saying invalid relational operator. Thank you for your time.

SELECT Col1 FROM mytable WHERE IF NULL Col2 = 0;

IF Col2 = NULL RETURN COL1 ELSE END IF;

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I apologize for the lack of information/Show of research. First post, So I have been searching google for different IF then statements to deal with NULL values. Everything I have found this far has only showed how to Ignore/convert to 0 so that you can easily work with them. Nothing on how to use them to return values from another col1

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Answer

SELECT Col1
FROM mytable
WHERE Col2 IS NULL

No IF is required. WHERE is the SQL IF for row selection. This returns only the rows where Col2 is null.

If you want to return all the rows, but want to return Col1 when Col2 is null and NULL otherwise, use

SELECT 
    CASE WHEN Col2 IS NULL THEN Col1 ELSE NULL END as myResultColumn
FROM mytable
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