COMPUTER SCIENCE AND ENGINEERING
SQL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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They are nested queries.
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Subqueries are executed first.
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Only one subquery can be nested.
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None of these.
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Detailed explanation-1: -Answer: C. Multi-row operators cannot be used in single-row sub-queries and vice versa.
Detailed explanation-2: -3. Which of the following statements are False regarding subqueries? Explanation: Only two subqueries can be placed at one level statements are False regarding subqueries.
Detailed explanation-3: -A subquery can be nested inside the WHERE or HAVING clause of an outer SELECT, INSERT, UPDATE, or DELETE statement, or inside another subquery. Up to 32 levels of nesting is possible, although the limit varies based on available memory and the complexity of other expressions in the query.
Detailed explanation-4: -A useful function in SQL is creating a query within a query, also known as a subquery or nested query. A nested query is a SELECT statement that is typically enclosed in parentheses, and embedded within a primary SELECT, INSERT, or DELETE operation.