Before establishing any kind of connection between front and back end which is your Java program and database. You should try to learn what precisely a JDBC is Why it came to existence and how to setup jdbc connection in java.
Today in this blog post we will discuss JDBC in detail and also resolve all your doubts related to the topic. If you are struggling with your java homework, just connect with our online programming experts to get your query resolved in no time.
You are probably not able to make a JDBC connection to complete your java project. Hence, you can rely on our java assignment online help to get done with it. If you are a student you can visit our official website for more exciting blogs like this. Let’s continue with JDBC..
- If you find this blog entry to be advanced, we recommend going to our basic blog entry on how to setup java environment.
- You can also read about top 10 tips to do your java homework before jumping into advanced concepts of java.
What is JDBC ?
We can understand JDBC as an acronym or Java database connectivity. Basically it is an advanced version of ODBC ( Open Database Connectivity ). With the help of JDBC we can move data from frontend to backend.
It is standard API specification. This API consists of classes and interfaces which are written in Java. The main purpose of JDBC is to provide a channel and work as an interface between your program and database. It helps to establish a link between the two. So that a programmer could send data from Java code and easily store it in the database for future purposes.
Why JDBC come into existence ?
We have earlier discussed that JDBC is an advanced version of ODBC, this version had a lot of drawbacks. ODBC API was written by using C, C + + Python, Core Java. As we all know except from Java and some parts of python, all mentioned languages are platform-dependent. And due to dependency, they were causing a lot of issues. To overcome this issue JDBC was developed by a database vendor that consists of interfaces in-class written in Java. So read further how java helpers at javahomeworkhelp.com give comprehensive detail about connection.
Steps for connectivity between Java program and database
Loading the Driver
When you begin, your first requirement is to load the driver or register it in the program. Registration is essential and it should be done once in your program.
You can register a driver by following way mentioned below:
Class.forName() : Load the driver’s class file into memory at the runtime. Without using new or creation of an object .The following example uses Class.forName() to load the Oracle driver Class.forName(“oracle.jdbc.driver.OracleDriver”);
DriverManager.registerDriver(): DriverManager is a Java inbuilt class with a static member register. Here we call the constructor of the driver class at compile time.
The following example uses DriverManager.registerDriver()to register the Oracle driver –DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver())
Create the connections
Establish connections using : Connection con = DriverManager.getConnection(URL,user,password)
user – username from which your SQL command prompt can be accessed.
password – password from which your SQL command prompt can be accessed.
con: is a reference to the Connection interface.
URL : Uniform Resource Locator. It can be created as follows:
String url = “ jdbc:oracle:thin:@localhost:1521:xe”
Create a statement
Once a connection is successfully established between program and database now you are allowed to interact with the database. You can use JDBC Statement, CallableStatement, and PreparedStatement interfaces methods that allow you to send SQL commands and receive data from your database.
Use of JDBC Statement is as follows:
Statement st = con.createStatement();
Here, con is a reference to Connection interface used in previous step .
Execute the query
The most important part you need to work with execution of the query. As we know there are multiple types of queries some of them are as follows:
Query for updating / inserting table in a database.
The query for retrieving data. We use The executeQuery() method of Statement interface to execute queries of retrieving values from the database. We use The executeUpdate(SQL query) method of statement interface to execute queries of updating/inserting .
Example:
int m = st.executeUpdate(sql);
if (m==1)
System.out.println(“inserted successfully : “+sql);
else
System.out.println(“insertion failed”);
Here sql is sql query of the type String
Close the connections
Finally, we have delivered the data to the specified location and we are on the verge of completing a task. Once we are done with the task we need to close the connection. For this, we use the by closing connection, objects of statement and resultset will be closed automatically. The close() method of the Connection interface is used to close the connection.
Example :
con.close();
Conclusion
So, this was the complete connectivity procedure for JDBC in Java and we hope you know how to setup jdbc connection in java. If you want to learn more concepts of java in an exciting and innovative way javahomeworkhelp.com and counter some exciting blogs and articles. Moreover, you can connect with out online chat support to discuss any further queries on jdbc connection issues and troubleshooting.
