Implementation to retrieve data from a ResultSet in JDBC
Below we have provided one example for ResultSet interface and Its functionality.
For this example,
- We already created one database named books in this database.
- Then, created one table named book with some data.
In this example, by using ResultSet we will see the data which is already exist in books table.
Note: We have already the Book table in Books database, and we have inserted some rows in book table. Now we will use this table for retrieve data from ResultSet in JDBC.
Data in Book Table:
Below we can see the existing Table and Its data.
Below is the example to retrieve data from a ResultSet in JDBC.
Java
// Java Program to retrieve data from a ResultSet in JDBC package w3wiki; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; // Driver Class public class RetrieveDataExample { // Main Function public static void main(String[] args) { try { // Load the MySQL JDBC driver Class.forName( "com.mysql.cj.jdbc.Driver" ); // Establish a connection to the database Connection con = DriverManager.getConnection( "jdbc:mysql://localhost:3306/books" , "root" , "password" ); if (con != null ) { // Prepare the SQL query to select all records from the book table String selectQuery = "SELECT * FROM book" ; PreparedStatement statement = con.prepareStatement(selectQuery); // Execute the query and retrieve the result set ResultSet resultSet = statement.executeQuery(); System.out.println( "The Available Data\n" ); // Iterate over the result set and print the retrieved data while (resultSet.next()) { int id = resultSet.getInt( "id" ); String author_name = resultSet.getString( "author" ); String book_name = resultSet.getString( "name" ); String book_price = resultSet.getString( "price" ); System.out.println( "ID: " + id + ", Author_Name: " + author_name + ", Book_Name: " + book_name + ", Book_Price " +book_price); } } else { System.out.println( "Not Connected..." ); } } catch (Exception e) { // Print any exceptions that occur during database access System.out.println( "Exception is " + e.getMessage()); } } } |
Output:
Here we have the output of the available data.
Explanation of the code:
In this above code, first we have created connection for MySQL database by using Connection class which is available in java.sql package. While connecting we need to provide some properties like Database URL, Username, Password.
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/books", "root", "password");
After this connection we write SQL query for selecting all records from the table by using PreparedStatement class with connection object. Refer below query statement for better understanding.
String selectQuery = "SELECT * FROM book";
PreparedStatement statement = con.prepareStatement(selectQuery);
Now we got result of SQL query. So, now we call the executeQuery method by using statement object.
Now we assign this result to ResultSet after that by using resultSet.next() in while we display the result in the console. (Already provided the output image above)
ResultSet resultSet = statement.executeQuery();
System.out.println("The Available Data\n");
while (resultSet.next()) {
int id = resultSet.getInt("id");
String author_name = resultSet.getString("author");
String book_name = resultSet.getString("name");
String book_price = resultSet.getString("price");
System.out.println("ID: " + id + ", Author_Name: " + author_name + ", Book_Name: "
+ book_name + ", Book_Price "+book_price);
}
How to Retrieve Data from a ResultSet in JDBC?
In Java database connectivity, the ResultSet is an interface, and it has a lot of built-in methods for handling the results of SQL queries. In this article, we will learn to retrieve data from a ResultSet in JDBC.