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SQL Basics

1/25 With SQL, how do you select all the columns from a table named "Products"?
- SELECT [all] FROM Products
- SELECT All Products
- SELECT *.Products
- SELECT * FROM Products
2/25 What SQL statement is used to extract data from a database?
- GET
- OPEN
- EXTRACT
- SELECT
3/25 Can the SELECT clause list have a computed value like in the example below? SELECT CustomerName, UnitPrice * NumberofUnits FROM Sale.
- No
- Yes
4/25 What does the TRUNCATE TABLE do?
- Deletes all rows from a table
- Deletes the table
- Checks if the table has primary key specified
5/25 Which SQL data type is used to store fixed-length character strings?
- VARCHAR
- TEXT
- CHAR
- STRING
6/25 What is the purpose of constraints in SQL?
- To limit the type of data that can be stored in a column.
- To join tables together based on a condition.
- To sort the data in ascending or descending order.
- To group data based on column values.
7/25 What is the purpose of the 'LIKE' operator in SQL?
- To compare a value to similar values using wildcard operators.
- To check for exact matches in a column.
- To perform mathematical operations.
- To limit the number of rows returned in a query.
8/25 What is the result of executing a SQL statement that includes a WHERE clause with a non-existent value?
- An error message.
- All records from the table.
- No records (an empty result set).
- The first record in the table.
9/25 What does the SQL clause 'LIMIT 10' do when added to a SELECT statement?
- Limits the result to the first 10 rows.
- Selects only the 10th row.
- Limits each column to 10 characters.
- Throws an error as 'LIMIT' is not a valid SQL clause.
10/25 In SQL, what does the 'BETWEEN' operator do?
- Checks whether a value lies within a specified range.
- Compares two values for equality.
- Sorts the result set between two columns.
- Divides the result set into two parts.
11/25 Which SQL statement is used to return the number of records in the 'Employees' table?
- COUNT(Employees)
- SELECT COUNT(*) FROM Employees
- GET NUMBER OF Employees
- SELECT ROWS FROM Employees
12/25 How do you perform a LEFT JOIN between 'Employees' and 'Departments' tables on the 'DepartmentID' column?
- SELECT * FROM Employees LEFT JOIN Departments ON Employees.DepartmentID = Departments.DepartmentID
- JOIN Employees, Departments USING (DepartmentID)
- SELECT * FROM Employees, Departments WHERE Employees.DepartmentID = Departments.DepartmentID
- SELECT * FROM Employees JOIN Departments ON DepartmentID
13/25 How do you rename a column 'EmployeeName' to 'FullName' in the 'Employees' table?
- ALTER TABLE Employees RENAME COLUMN EmployeeName TO FullName
- UPDATE TABLE Employees CHANGE EmployeeName FullName
- ALTER TABLE Employees MODIFY COLUMN EmployeeName AS FullName
- RENAME COLUMN EmployeeName TO FullName IN Employees
14/25 Which SQL clause is used to filter the results of a GROUP BY operation?
- FILTER BY
- HAVING
- WHERE
- GROUP WHERE
15/25 What does the following SQL statement do: SELECT EmployeeName, SUM(Salary) OVER (PARTITION BY DepartmentID) FROM Employees?
- Summarizes the total salary for each department
- Displays an error as the syntax is incorrect
- Displays the sum of salaries within each department for each employee
- Calculates the overall sum of salaries in the Employees table
16/25 Which statement is used to add a new row to a table in SQL?
- ADD ROW INTO tableName (column1, column2) VALUES (value1, value2)
- INSERT INTO tableName (column1, column2) VALUES (value1, value2)
- CREATE ROW IN tableName (column1, column2) VALUES (value1, value2)
- APPEND INTO tableName (column1, column2) VALUES (value1, value2)
17/25 What is the primary purpose of the SQL 'INNER JOIN' clause?
- To combine rows from two or more tables based on a related column between them
- To retrieve rows that exist in one table but not in another
- To select all rows from both tables regardless of the match between columns
- To update records in one table based on values in another table
18/25 Which SQL clause is used to specify a condition while fetching data from a single table or joining multiple tables?
- HAVING
- WHERE
- ON
- AND
19/25 Which SQL function is used to return the largest value of the selected column?
- MAX()
- BIG()
- UPPER()
- TOP()
20/25 What is the purpose of the 'GROUP BY' clause in SQL?
- To group rows that have the same values in specified columns into summary rows
- To group the output of a SQL query by the values of a specific column
- To sort the result set of a query by the specified column values
- To filter rows based on the condition specified by the aggregate function
21/25 In SQL, what is a subquery?
- A query within another query
- A function used to pass parameters to a query
- A method to rename a query
- A special operator to join queries
22/25 How can you insert multiple rows into a table named 'Orders'?
- INSERT INTO Orders VALUES (value1, value2), (value3, value4)
- INSERT MULTIPLE INTO Orders VALUES (value1, value2), (value3, value4)
- ADD INTO Orders VALUES (value1, value2), (value3, value4)
- INSERT INTO Orders VALUES (value1, value2) AND (value3, value4)
23/25 Which SQL clause is used to sort the result set in ascending or descending order?
- SORT BY
- ORDER BY
- ARRANGE BY
- SEQUENCE BY
24/25 In SQL, which command is used to add a new column to an existing table?
- ADD COLUMN column_name TO table_name
- INSERT COLUMN column_name INTO table_name
- ALTER TABLE table_name ADD column_name column_type
- UPDATE TABLE table_name SET ADD column_name column_type
25/25 What does the SQL 'CROSS JOIN' clause do?
- Joins two tables in such a way that each row of the first table is combined with each row of the second table
- Joins only the matching rows between two tables
- Creates a join that can be filtered using a WHERE clause
- Combines rows from two tables based on a related column
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