JDBC - Prepared Statement Object Examples

Following is the example, which makes use of the PreparedStatement along with opening and closing statements −

This sample code has been written based on the environment and database setup done in the previous chapters.

Using PreparedStatement to Update int Value Example

In this example, we've five static strings containing a dababase connection url, username, password, SELECT Query and an UDPATE query. UPDATE Query has placeholders for age and id which will be filled by PreparedStatement. Now using DriverManager.getConnection() method, we've prepared a database connection. Once connection is prepared, we've created a PreparedStatement object using connection.prepareStatement() method. Now using setInt() method, we've set the placeholder values of age and id accordingly.

Using statement.executeUpdate(), we've run the update query and modified row count is stored in rows variable. Lastly using statement.executeQuery(), the SELECT Query is executed and result is stored in a resultset. Now resultset is iterated and each record is printed to check the updated content.

Copy and paste the following example in JDBCPreparedStatementExample.java, compile and run as follows −

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class JDBCPreparedStatementExample {
   static final String DB_URL = "jdbc:mysql://localhost/TUTORIALSPOINT";
   static final String USER = "guest";
   static final String PASS = "guest123";
   static final String QUERY = "SELECT id, first, last, age FROM Employees";
   static final String UPDATE_QUERY = "UPDATE Employees set age=? WHERE id=?";

   public static void main(String[] args) {
      // Open a connection
      try(Connection conn = DriverManager.getConnection(DB_URL, USER, PASS);
         PreparedStatement stmt = conn.prepareStatement(UPDATE_QUERY);
      ) {		      
         // Bind values into the parameters.
         stmt.setInt(1, 35);  // This would set age
         stmt.setInt(2, 102); // This would set ID

         // Let us update age of the record with ID = 102;
         int rows = stmt.executeUpdate();
         System.out.println("Rows impacted : " + rows );

         // Let us select all the records and display them.
         ResultSet rs = stmt.executeQuery(QUERY);		      

         // Extract data from result set
         while (rs.next()) {
            // Retrieve by column name
            System.out.print("ID: " + rs.getInt("id"));
            System.out.print(", Age: " + rs.getInt("age"));
            System.out.print(", First: " + rs.getString("first"));
            System.out.println(", Last: " + rs.getString("last"));
         }
         rs.close();
      } catch (SQLException e) {
         e.printStackTrace();
      } 
   }
}

Output

Now let us compile the above example as follows −

C:\>javac JDBCPreparedStatementExample.java
C:\>

When you run JDBCPreparedStatementExample, it produces the following result −

C:\>java JDBCPreparedStatementExample
Return value is : false
Rows impacted : 1
ID: 100, Age: 18, First: Zara, Last: Ali
ID: 101, Age: 25, First: Mehnaz, Last: Fatma
ID: 102, Age: 35, First: Zaid, Last: Khan
ID: 103, Age: 30, First: Sumit, Last: Mittal
C:\>

Using PreparedStatement to Update String Value Example

In this example, we've five static strings containing a dababase connection url, username, password, SELECT Query and an UDPATE query. UPDATE Query has placeholders for age and id which will be filled by PreparedStatement. Now using DriverManager.getConnection() method, we've prepared a database connection. Once connection is prepared, we've created a PreparedStatement object using connection.prepareStatement() method. Now using setString() method, we've set the placeholder values of dept and using setInt() method, we've set the id accordingly.

Using statement.executeUpdate(), we've run the update query and modified row count is stored in rows variable. Lastly using statement.executeQuery(), the SELECT Query is executed and result is stored in a resultset. Now resultset is iterated and each record is printed to check the updated content.

Copy and paste the following example in JDBCPreparedStatementExample.java, compile and run as follows −

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class JDBCPreparedStatementExample {
   static final String DB_URL = "jdbc:mysql://localhost/TUTORIALSPOINT";
   static final String USER = "guest";
   static final String PASS = "guest123";
   static final String QUERY = "SELECT StudentID, LastName, FirstName, Dept FROM Students";
   static final String UPDATE_QUERY = "UPDATE Students set Dept=? WHERE studentid=?";

   public static void main(String[] args) {
      
        try{
          // Open a connection
          Connection conn = DriverManager.getConnection(DB_URL, USER, PASS);
         PreparedStatement pstmt = conn.prepareStatement(UPDATE_QUERY);
              
         // Bind values into the parameters.
         pstmt.setString(1, "Mathematics");  
         pstmt.setInt(2, 1000); 

         // Updating Dept of the record with StudentID = 1000
         int rows = pstmt.executeUpdate();
         System.out.println("Rows impacted : " + rows );

         // Let us select all the records and display them.
         ResultSet rs = pstmt.executeQuery(QUERY);		      

         // Extract data from result set
         while (rs.next()) {
            // Retrieve by column name
            System.out.print("ID: " + rs.getInt("StudentID"));
            System.out.print(", LastName: " + rs.getString("LastName"));
            System.out.print(", FirstName: " + rs.getString("FirstName"));
            System.out.println(", Dept: " + rs.getString("Dept"));
         }
         rs.close();
         pstmt.close();
      } catch (SQLException e) {
         e.printStackTrace();
      } 
      
   }
}

Output

Now let us compile the above example as follows −

C:\>javac JDBCPreparedStatementExample.java
C:\>

When you run JDBCPreparedStatementExample, it produces the following result −

C:\>java JDBCPreparedStatementExample

Rows impacted : 1
ID: 1000, LastName: Agarwal, FirstName: Bonny, Dept: Mathematics
ID: 1001, LastName: Pandey, FirstName: Amit, Dept: Physics
ID: 1002, LastName: Kumar, FirstName: Shefali, Dept: English
ID: 1004, LastName: Ali, FirstName: Mohammed, Dept: Mathematics
ID: 1005, LastName: Kumar, FirstName: Kishore, Dept: Biology

C:\>
jdbc-statements.htm
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