Reda AZIZI
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Question of
What does SQL stand for?
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Structured Language
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Sequential Query Language
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Structured Query Language
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Systematic Query Language
Correct Wrong
Explanation: SQL stands for Structured Query Language, and it is a domain-specific language used for managing and manipulating relational databases.
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Question of
Which SQL clause is used to filter the results of a query?
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GROUP BY
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ORDER BY
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WHERE
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HAVING
Correct Wrong
Explanation: The WHERE clause is used to filter the results of a query based on a specified condition.
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Question of
Which SQL command is used to retrieve all the columns from a table named “employees”?
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SELECT * FROM employees;
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SHOW COLUMNS FROM employees;
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DESCRIBE employees;
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SELECT ALL FROM employees;
Correct Wrong
Explanation: The SELECT statement is used to retrieve data from a database. The asterisk (*) is used to select all columns, and "employees" is the name of the table.
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Question of
In SQL, which data type is used to store a date?
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VARCHAR
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DATE
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INT
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FLOAT
Correct Wrong
Explanation: The DATE data type in SQL is used to store date values.
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Question of
What is the purpose of the SQL JOIN clause?
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To combine rows from different tables based on a related column between them
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To filter rows based on a specified condition.
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To sort the result set in ascending or descending order.
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To group rows that have the same values in specified columns.
Correct Wrong
Explanation: The JOIN clause is used to combine rows from two or more tables based on a related column.
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Question of
Which SQL statement is used to update data in a table?
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ALTER
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UPDATE
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MODIFY
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CHANGE
Correct Wrong
Explanation: The UPDATE statement is used to modify existing records in a table.
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Question of
What is the function of the SQL GROUP BY clause?
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To filter rows based on a specified condition.
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To join tables based on a related column.
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To group rows that have the same values in specified columns.
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To sort the result set in ascending or descending order.
Correct Wrong
Explanation: The GROUP BY clause is used to group rows based on the values in specified columns.
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Question of
Which SQL command is used to remove a table from the database?
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REMOVE TABLE table_name;
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DROP TABLE table_name;
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DELETE TABLE table_name;
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REMOVE FROM table_name;
Correct Wrong
Explanation: The DROP TABLE statement is used to remove a table from the database.
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Question of
Which of the following is not a valid SQL aggregate function?
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COUNT
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AVG
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TOTAL
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SUM
Correct Wrong
Explanation: The ORDER BY clause is used to sort the result set in ascending or descending order based on one or more columns.
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Question of
In SQL, what is the purpose of the ORDER BY clause?
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To filter rows based on a specified condition.
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To join tables based on a related column.
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To sort the result set in ascending or descending order.
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To group rows that have the same values in specified columns.
Correct Wrong
Explanation: The correct aggregate function is SUM, not TOTAL. SQL aggregate functions include COUNT, AVG, SUM, and others for performing operations on sets of values. "TOTAL" is not a recognized aggregate function in standard SQL.
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