Upwork/oDesk JDBC 2.1 Test

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1. Please select all the correct options. JDBC Driver Manager is:
Answers:
• Able to activate registered drivers
• Able to activate unregistered drivers
• Not required for activation of drivers with DataSource
• Required for activation of drivers with DataSource

2. Under which category does the following driver fall:

WebLogic's Tengah "all Java Type-3 driver"
Answers:
• JDBC-ODBC Bridge Driver
• Native-API Partly-Java Driver
• Net-Protocol All-Java Driver
• Native-Protocol All-Java Driver
• Native-Protocol Part-Java Driver
3. Which JDBC driver is considered best in terms of performance and efficiency?
Answers:
• Type-1 Driver
• Type-2 Driver
• Type-3 Driver
• Type-4 Driver
4. Consider the following statement:

PreparedStatement ps=con.prepareStatement("INSERT INTO ORDER (CUSTOMER_ID ,PRICE) VALUES(?,?)");

Which of the following should come after this statement?
Answers:
• ps.clearParameters(); ps.setInt(1,3); ps.setDouble(2,790.50); ps.executeUpdate(sql);
• ps.clearParameters(); ps.setInt(1,3); ps.setDouble(2,790.50); ps.executeUpdate();
• ps.clear(); ps.setInt(1,3); ps.setDouble(2,790.50); ps.executeUpdate(sql);
• ps.clearParameters(); ps.setInt(1,3.09); ps.setDouble(2,790.50); ps.execute(sql);
• ps.clearParameters(); ps.setDouble(2,790.50); ps.execute(sql);
5. You want to start a transaction for bank account processing. Which of the following methods will you execute on the Connection object to begin it?
Answers:
• con.setAutoCommit(false);
• con.setCommit(false);
• con.setAutoCommit();
• con.setAutoCommit(true);
• con.autoCommit();
6. You need to use a third party driver for establishing a connection with the database. The subprotocol is "webx" and the DSN is "webdsn". What is the syntax of the URL?
Answers:
• jdbc:odbc:webx:webdsn
• odbc:jdbc:webx:webdsn
• jdbc:webx:webdsn
• thin:jdbc:odbc:dsn:webdsn
• thick:jdbc:odbc:dsn:webdsn
• None of the above
7. You have to handle an erroneous situation in a transaction. Which method comes handy in this case?
Answers:
• con.commit(false);
• con.commit();
• con.rollback();
• con.revertback();
• con.rollback(true);
8. How will you create a new instance of a JDBC driver explicitly?
Answers:
• Class.forName("driver");
• Class.newInstance("driver");
• Class.driver("driver");
• Class.getDriver("driver");
• Class.forName("driver").newInstance();
9. JDBC is based on:
Answers:
• X/Open CLI (Call Level Interface)
• JDBC/Open CLI
• Java/Open CLI
• V/OPEN CLI
• X/Close CLI
10. You are developing a shopping cart for your client. Where would you like to put your business logic?
Answers:
• Inside the database
• Inside the client application
• In middleware servlets
• In COM / DCOM components
• Inside the code for the cart
11. You want to execute the following query string, using the connection named "con":

String query = "SELECT * FROM CUSTOMER";

What should the syntax be?
Answers:
• Statement stmt=con.createStatement(); ResultSet rs=stmt.executeQuery(query);
• Statement stmt=new Statement(); ResultSet rs=stmt.executeQuery(query);
• Statement stmt=con.createStatement(); ResultSet rs=stmt.execute(query);
• Statement stmt=con.getStatement(); ResultSet rs=stmt.executeQuery(query);
• Statement stmt=con.getStatement(); ResultSet rs=con.executeQuery(query);
12. Which exception will be thrown in your code, if the specified driver could not be loaded?
Answers:
• ActivationException
• ClassNotFoundException
• ClassNotAvailableException
• ClassUnavailableException
• InstantiationException
13. A process allows you to group multiple SQL statements. Commit or Rollback can be performed on the group together. This process is known as:
Answers:
• Binding
• Synchronization
• Registry
• Transaction
• Late binding
14. Which of the following JDBC methods is used for retrieving large text strings?
Answers:
• getBinaryStream
• getText
• getAsciiStream
• getString
• getObjectStream
15. Open Database Connectivity is:
Answers:
• Platform independent
• Platform dependent
• Architecture neutral
• Network independent
• Machine independent
16. Which of the following methods eliminates the need to call wasNull() method to handle null database fields?
Answers:
• getObject();
• getInt();
• getString();
• getFloat();
• getNull();
17. Transactions have a property called atomicity, which means:
Answers:
• Everything takes place one by one
• Everything takes place once
• Everything takes place randomly
• Everything takes place twice
• Everything takes place thrice
18. What should the syntax be to establish a connection with a Database?
Answers:
• Connection con = DriverManager.getConnection(url,"myLogin", "myPassword");
• Connection con = DriverManager.getConnection("myLogin", "myPassword",url);
• Connection con = DriverManager.getConnection("myLogin", "myPassword");
• Connection con = DriverManager.setConnection(url,"myLogin", "myPassword");
• Connection con = DriverManager.createConnection(url,"myLogin", "myPassword");
19. ResultSet objects follow index patterns of:
Answers:
• Array standard
• Java standard
• RDBMS standard
• C++ standard
• PL/SQL standard
20. When you are handling user-submitted SQL, you may retrieve a ResultSet or a count. Which of the following methods is handy in this situation?
Answers:
• executeQuery()
• exceuteUpdate()
• execute()
• executeQueryUpdate()
• update()
21. You want to execute a CallableStatement named 'cs'. It is expected to return multiples results. Which of the following methods will you choose?
Answers:
• ResultSet rs=cs.execute()
• ResultSet rs=cs.executeQuery()
• ResultSet rs=cs.executeUpdate()
• ResultSet rs=cs.executeQuery(sql)
• ResultSet rs=execute()
22. Your project leader has asked you to improve the performance of JDBC connectivity by reusing objects in your Servlet's code. Which of the following is an appropriate solution?
Answers:
• Reuse the database connection and reuse PreparedStatement objects
• Reuse the database connection and use PreparedStatement objects with synchronized blocks
• Reuse the database connection only
• Reuse the PreparedStatement objects only
• Reuse the GetPreparedStatement objects only
23. Which of the following methods will you use to execute INSERT, UPDATE and DELETE SQL statements?
Answers:
• executeQuery();
• executeUpdate();
• executeQueryUpdate();
• update();
• query();
24. How do you register a JDBC driver?
Answers:
• Class.forName("driver");
• Class.newInstance("driver");
• Class.driver("driver");
• Class.getDriver("driver");
• Class.postDriver("driver");
25. Which of the following JDBC methods is used for retrieving large binary objects?
Answers:
• getBinaryStream
• getText
• getAsciiStream
• getString
• getObjectStream
26. Name the interface you will use to retrieve the underlying structure of the query result:
Answers:
• ResultSet
• ResultSetMetaData
• ResultStructure
• Result
• ResultMetaData
27. Which type of statement object will you use to execute a stored procedure?
Answers:
• Statement
• PreparedStatement
• CallableStatement
• StoredStatement
• Stat
28. A warning can be thrown by a Connection object, a Statement object or a  ResultSet object. Which method is used to retrieve the warning:
Answers:
• getWarnings()
• getWarned()
• getWarning()
• getError()
• getErrorsWarning()
29. You have obtained a ResultSet object named 'rs' after executing the following query:

SELECT * FROM CUSTOMER

Which loop can you use to return all the records in the ResultSet?
Answers:
• while(rs.next())
• while(rs.hasNext())
• while(true)
• while(rs.nextElement())
30. You executed a query to retrieve 40 products from the database and obtained a scrollable ResultSet named 'scrollrs'. You started scrolling the ResultSet as follows:

scrollrs.next();
scrollrs.absolute(-10);
scrollrs.relative(-6);

At which row number is the cursor currently located?
Answers:
• 16
• 24
• 26
• 17
• 6
31. The code segment below defines a query:

String qry="SELECT CUS_NAME, PRICE FROM CUSTOMER";

Which of the following code snippets will create a scrollable ResultSet?
Answers:
• Statement st=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY); ResultSet srs=st.executeQuery(qry);
• Statement st=con.createStatement(qry,ResultSet.CONCUR_READ_ONLY,ResultSet.TYPE_SCROLL_SENSITIVE); ResultSet srs=st.executeQuery();
• Statement st=con.createStatement(qry,ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY); ResultSet srs=st.executeQuery();
• Statement st=con.createStatement(ResultSet.CONCUR_READ_ONLY,ResultSet.TYPE_SCROLL_SENSITIVE); ResultSet srs=st.executeQuery(qry);
32. Which of the following is the syntax for creating a CallableStatement?
Answers:
• CallableStatement cs=con.prepareCall("{call SHOW_ORDER}")
• CallableStatement cs=con.prepareCall('{call SHOW_ORDER}')
• CallableStatement cs=con.prepareCall("(call SHOW_ORDER)")
• CallableStatement cs=con.prepareCall("call SHOW_ORDER")
• CallableStatement cs=prepareCall("call SHOW_ORDER")
33. Which of the following is not true for a ResultSet?
Answers:
• JDBC 2.0 API supports Scrollable ResultSets
• ResultSet cursors are moved forward using next() method
• ResultSet cursors are moved backwards using previous() method
• Methods next() and previous() return -1 beyond the ResultSet
34. Java Database Connectivity (JDBC) is a:
Answers:
• Database-dependent API
• Database-independent API
• Machine-dependent API
• Network-dependent database API
35. Servlet developers should avoid using JDBC-ODBC bridge driver because:
Answers:
• Drivers are bundled with JDK
• The driver's native code can crash the entire server
• The driver is not secure
• The driver is of Type-1
• The driver is of Type-2
36. You have obtained a scrollable ResultSet named 'srs' by executing a query. Which of the following methods will you use to verify the position of the cursor?
Answers:
• srs.relative(-4)
• srs.relative()
• srs.absolute(-4)
• srs.getRow()
• srs.postRow()
37. A user leaves an online shopping cart without checking out. Which of following interfaces will notify to Rollback the transaction?
Answers:
• HttpSession
• HttpSessionBindingListener
• HttpServlet
• SingleThreadModel
• FtpSession
38. After executing the following code, resultvar contains false. What should the next step be?

boolean resultvar=stmt.execute(sql);
Answers:
• stmt.getResultSet();
• stmt.getUpdateCount();
• stmt.executeUpdate();
• stmt.executeQuery();
• stmt.executeUpdateQuery();
39. SQLException has a method, which provides the feature of chaining or encapsulation of additional Exception objects. Identify the method from the following:
Answers:
• getEncapsulatedException()
• getEncapException()
• getMessage()
• getNextException()
• getException()
40. Your project leader has given you a new task. You have to work on a module in which the transaction has to be extended across multiple page requests and multiple servlets. How will you implement this?
Answers:
• By synchronizing the doPost() method
• By creating a new connection for each transaction
• By session tracking and using HttpSession to hold a connection for each user
• By creating a single connection in the init() method and implementing SingleThreadModel
• By synchronizing doGet ()
41. SQLWarning object deals with database access warnings. It is a subclass of:
Answers:
• SQLWarn
• SQLException
• SQLError
• SQLWarning
• SQLErrorsWarning
42. Will the below script execute properly?

1.CREATE TABLE CUSTOMER       
2.(
3.CUS_NAME VARCHAR(32), SUP_ID INTEGER, PRICE FLOAT, SALES INTEGER
4.)
Answers:
• Yes. The table will be created successfully.
• No. Line 3 should be modified to: VARCHAR(32) CUS_NAME,INTEGER SUP_ID ,FLOAT PRICE , INTEGER SALES
• No. Line 3 should be modified to: 'CUS_NAME VARCHAR(32)','SUP_ID INTEGER',' PRICE FLOAT', 'SALES INTEGER'
• No. Line 3 should be modified to: 'CUS_NAME' VARCHAR(32),'SUP_ID' INTEGER,'PRICE' FLOAT, 'SALES' INTEGER
43. You are trying to connect to a database through JDBC. There is a problem with one of the methods immediately after the driver has been loaded. Which exception will be thrown?
Answers:
• ClassNotFoundException
• SQLException
• SQLNotFoundException
• ActivationException
• JDBCException

44. Which of the following is not true?
Answers:
• CallableStatement is a subclass of PreparedStatement
• CallableStatement can take PreparedStatement as an input parameter
• CallableStatement can use executeUpdate() method
• CallableStatement can use execute() method
• CallableStatement cannot take INOUT parameters