U3.3. PreparedStatements (JDBC)

Which of the following statements about PreparedStatements is true?

• • PreparedStatements cannot accept parameters.

• • PreparedStatements are precompiled SQL statements.

• PreparedStatements are only used for SELECT statements.

• • PreparedStatements are slower than regular Statements.

Which method is used to create a PreparedStatement in JDBC?

• Connection.createStatement()

• • Connection.prepareCall()

• Connection.prepareStatement()

• Connection.setStatement()

Why is PreparedStatement recommended for user input compared to Statement?

• • It allows dynamic table names.

• • It’s faster than Statement.

• It protects against SQL injection attacks.

• It automatically handles connections.

What does the following code do?

• • Inserts a new employee named Manuel, age 30, into the employees table.

• • Updates the employees table by setting age to 30 for Manuel.

• • Selects employees with name Manuel and age 30.

• • Deletes an employee named Manuel.

In the following code, what does ? represent?

• A table name placeholder

• A column name placeholder

• A parameter placeholder

• A SQL function

Which method would you use to set an integer parameter in a PreparedStatement?

• setInt()

• setInteger()

• setNumber()

• setParamInt()

What is the correct way to set the first parameter in a PreparedStatement to the string "Vicente"?

• stt.setString(0, "Vicente");

• stt.setString(1, "Vicente");

• stt.setString(2, "Vicente");

• stt.setName(1, "Vicente");

How do PreparedStatements help improve performance in SQL operations?

• • They cache the database connection.

• • They only allow one-time use of the SQL statement.

• • They allow pre-compilation of SQL, reducing parsing time for repeated queries.

• • They store the results for faster retrieval.

Which of these statements would cause an error in a PreparedStatement and why?

• • No error. This is a valid PreparedStatement.

• • It will cause an error because PreparedStatements cannot replace table names with ?.

• • It will cause an error because setString must be used instead of setInt.

• It will cause an error because ? can only be used for INSERT statements.

Which method is used to execute an INSERT statement with a PreparedStatement?

• executeInsert()

• • executeQuery()

• executeUpdate()

• executeStatement()

Answer explanation

• executeQuery() → for SELECT queries

• executeUpdate() → for INSERT, UPDATE, DELETE or DDL