SQL Select

What is the basic syntax for a SQL SELECT statement?

• SELECT FROM table_name;

• SELECT * FROM table_name;

• SELECT column1, column2 FROM table_name;

• SELECT column1, column2, ... FROM table_name;

How can you filter rows in a SQL SELECT statement using the WHERE clause?

• SELECT * FROM table_name WHERE column_name <> 'value';

• SELECT * FROM table_name WHERE column_name != 'value';

• SELECT * FROM table_name WHERE column_name LIKE 'value';

• SELECT * FROM table_name WHERE column_name = 'value';

What is the purpose of the ORDER BY clause in a SQL SELECT statement?

• To delete records from the table

• To sort the result set based on specified columns in ascending or descending order.

• To update records in the table

• To create a new table

How can you retrieve only unique values in a SQL SELECT statement using the DISTINCT keyword?

• SELECT DISTINCT * FROM table_name;

• SELECT DISTINCT column_name FROM table_name;

• SELECT column_name FROM table_name GROUP BY column_name;

• SELECT UNIQUE column_name FROM table_name;

In a SQL SELECT statement, what does the '*' symbol represent?

• Select all columns

• Select all rows

• Select all tables

• Select all databases

What is the difference between WHERE and HAVING clauses in a SQL SELECT statement?

• The WHERE clause is used for numeric comparisons, while the HAVING clause is used for string comparisons.

• The WHERE clause is used for filtering columns, while the HAVING clause is used for filtering rows.

• The WHERE clause is used to filter rows before any groupings are made, while the HAVING clause is used to filter rows after the grouping is done.

• The WHERE clause can only be used with aggregate functions, while the HAVING clause can only be used with regular functions.

How can you sort the result set in descending order in a SQL SELECT statement?

• SELECT * FROM table_name ORDER BY column_name DESC;

• SELECT * FROM table_name ORDER column_name DESC;

• SELECT * FROM table_name SORT BY column_name DESC;

• SELECT * FROM table_name ORDER BY column_name ASC;

What is the purpose of the LIMIT clause in a SQL SELECT statement?

• To restrict the number of rows returned by the query result.

• To filter rows based on a condition

• To sort the rows in ascending order

• To update the values in the selected rows

Explain the difference between the GROUP BY and ORDER BY clauses in a SQL SELECT statement.

• The GROUP BY clause filters rows, while the ORDER BY clause groups rows.

• The GROUP BY clause sorts rows, while the ORDER BY clause groups rows.

• The GROUP BY clause groups rows, while the ORDER BY clause sorts rows.

• The GROUP BY clause orders rows, while the ORDER BY clause filters rows.

How can you perform calculations on columns in a SQL SELECT statement?

• Use functions like SUM(), AVG(), COUNT(), etc. along with column names in the SELECT statement.

• Create a separate table to store the calculated values and join it with the original table in the SELECT statement

• Perform calculations directly within the WHERE clause of the SELECT statement

• Use functions like SUBTRACT(), MULTIPLY(), DIVIDE() along with column names in the SELECT statement