Multiple choice technology testing

How many columns are presented after executing this query: SELECT address1||','||address2||','||address2 "Adress" FROM employee;

  1. 1

  2. 2

  3. 3

  4. 0

  5. 4
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A Correct answer
Explanation

The query uses string concatenation operators to combine multiple columns into a single expression aliased as Adress. Regardless of how many columns are concatenated inside the expression, the SELECT clause projects only one resulting column.

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