Prepare Interview

Exams Attended

Mock Exams

Make Homepage

Bookmark this page

Subscribe Email Address

JDBC Interview Questions and Answers

Test your skills through the online practice test: JDBC Quiz Online Practice Test

Intermediate / 1 to 5 years experienced level questions & answers

Ques 1. What is Connection pooling?

Connection pooling is a technique used for sharing server resources among requesting clients. Connection pooling increases the performance of Web applications by reusing active database connections instead of creating a new connection with every request. Connection pool manager maintains a pool of open database connections.

Is it helpful? Add Comment View Comments
 

Ques 2. Is JDBC-ODBC bridge multi-threaded?

No

Is it helpful? Add Comment View Comments
 

Ques 3. Does the JDBC-ODBC Bridge support multiple concurrent open statements per connection?

No

Is it helpful? Add Comment View Comments
 

Ques 4. How can you move the cursor in scrollable result sets?

One of the new features in the JDBC 2.0 API is the ability to move a result set’s cursor backward as well as forward. There are also methods that let you move the cursor to a particular row and check the position of the cursor.
Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_READ_ONLY);
ResultSet srs = stmt.executeQuery("SELECT EMP_NAME, SAL FROM EMPLOYEE");

The first argument is one of three constants added to the ResultSet API to indicate the type of a ResultSet object: TYPE_FORWARD_ONLY, TYPE_SCROLL_INSENSITIVE , and TYPE_SCROLL_SENSITIVE. The second argument is one of two ResultSet constants for specifying whether a result set is read-only or updatable: CONCUR_READ_ONLY and CONCUR_UPDATABLE. The point to remember here is that if you specify a type, you must also specify whether it is read-only or updatable. Also, you must specify the type first, and because both parameters are of type int , the compiler will not complain if you switch the order. Specifying the constant TYPE_FORWARD_ONLY creates a nonscrollable result set, that is, one in which the cursor moves only forward. If you do not specify any constants for the type and updatability of a ResultSet object, you will automatically get one that is TYPE_FORWARD_ONLY and CONCUR_READ_ONLY.

Is it helpful? Add Comment View Comments
 

Ques 5. What’s the difference between TYPE_SCROLL_INSENSITIVE , and TYPE_SCROLL_SENSITIVE?

You will get a scrollable ResultSet object if you specify one of these ResultSet constants.The difference between the two has to do with whether a result set reflects changes that are made to it while it is open and whether certain methods can be called to detect these changes. Generally speaking, a result set that is TYPE_SCROLL_INSENSITIVE does not reflect changes made while it is still open and one that is TYPE_SCROLL_SENSITIVE does. All three types of result sets will make changes visible if they are closed and then reopened:
Statement stmt =
con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
ResultSet srs =
stmt.executeQuery("SELECT EMP_NAME, SAL FROM EMPLOYEE");
srs.afterLast();
while (srs.previous())
{
String name = srs.getString("EMP_NAME");
float sal = srs.getFloat("SAL");
System.out.println(name + " " + sal);
}

Is it helpful? Add Comment View Comments
 

Ques 6. How to Make Updates to Updatable Result Sets?

Another new feature in the JDBC 2.0 API is the ability to update rows in a result set using methods in the Java programming language rather than having to send an SQL command. But before you can take advantage of this capability, you need to create a ResultSet object that is updatable. In order to do this, you supply the ResultSet constant CONCUR_UPDATABLE to the createStatement method.
Connection con =
DriverManager.getConnection("jdbc:mySubprotocol:mySubName");
Statement stmt =
con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
ResultSet uprs =
stmt.executeQuery("SELECT EMP_NAME, SAL FROM EMPLOYEE");

Is it helpful? Add Comment View Comments
 

Most helpful rated by users:

Related differences

JDBC vs JPA

Related interview subjects

JUnit interview questions and answers - Total 24 questions
Spring Framework interview questions and answers - Total 53 questions
Java Design Patterns interview questions and answers - Total 15 questions
Core Java interview questions and answers - Total 306 questions
Tomcat interview questions and answers - Total 16 questions
Apache Wicket interview questions and answers - Total 26 questions
Java Applet interview questions and answers - Total 29 questions
JAXB interview questions and answers - Total 18 questions
JMS interview questions and answers - Total 64 questions
Log4j interview questions and answers - Total 35 questions
Struts interview questions and answers - Total 84 questions
RMI interview questions and answers - Total 31 questions
Apache Camel interview questions and answers - Total 20 questions
JDBC interview questions and answers - Total 27 questions
Java 11 interview questions and answers - Total 24 questions
JPA interview questions and answers - Total 41 questions
EJB interview questions and answers - Total 80 questions
GWT interview questions and answers - Total 27 questions
Kotlin interview questions and answers - Total 30 questions
Glassfish interview questions and answers - Total 8 questions
Google Gson interview questions and answers - Total 8 questions
JSP interview questions and answers - Total 49 questions
J2EE interview questions and answers - Total 25 questions
Apache Tapestry interview questions and answers - Total 9 questions
Java Swing interview questions and answers - Total 27 questions
Java Mail interview questions and answers - Total 27 questions
Hibernate interview questions and answers - Total 52 questions
JSF interview questions and answers - Total 24 questions
Java 8 interview questions and answers - Total 30 questions
Java 15 interview questions and answers - Total 16 questions
JBoss interview questions and answers - Total 14 questions
Web Services interview questions and answers - Total 10 questions
RichFaces interview questions and answers - Total 26 questions
Servlets interview questions and answers - Total 34 questions
Java Beans interview questions and answers - Total 57 questions
Spring Boot interview questions and answers - Total 50 questions
©2023 WithoutBook