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Introduction to SQL MCQs

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Practice free Introduction to SQL multiple-choice questions with instant answer feedback and step-by-step solutions. Click an option to check yourself, reveal the full explanation, and work through all 73 questions — no login required.

Question 46easy

Each index consumes extra storage space and also requires overhead maintenance time whenever indexed data change value.

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Question 47easy

The HAVING clause acts like a WHERE clause, but it identifies groups that meet a criterion, rather than rows.

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Question 48easy

SQL is a data sublanguage.

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Question 49easy

The qualifier DISTINCT must be used in an SQL statement when we want to eliminate duplicate rows.

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Question 50easy

DISTINCT and its counterpart, ALL, can be used more than once in a SELECT statement.

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Question 51easy

The result of every SQL query is a table.

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Question 52easy

COUNT(field_name) tallies only those rows that contain a value; it ignores all null values.

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Question 53easy

SUM, AVG, MIN, and MAX can only be used with numeric columns.

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Question 54easy

Most companies keep at least two versions of any database they are using.

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