A.6. Chapter 6

  1. A subquery is allowed in which parts of a SQL SELECT statement?

    Answer: A subquery is allowed in the SELECT clause, the FROM clause, and the WHERE clause.

  2. True or false: A correlated subquery references a table in the SELECT clause.

    Answer: False, the correlated subquery references a column in the main query.

  3. Which set operator will not remove duplicate rows from the result of a compound query?

    Answer: UNION ALL will not remove duplicate rows from the result of a compound query.

  4. What characteristics of the columns in a compound query using INTERSECT must match?

    Answer: The number of columns and their datatypes must match in a compound query using INTERSECT. The lengths of the columns and the names do not need to match.

  5. How are NULL values ...

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