The Java java.sql.Statement interface is used to execute SQL statements against a relational database. You obtain a JDBC Statement from a JDBC Connection. Once you have a Java Statement instance you can execute either a database query or a database update with it.
Learn Java JDBC at https://www.javaguides.net/p/jdbc-tutorial.html
JDBC Statement Example - Select Records
In this example, we will use the executeQuery() method to select records from a database table using the JDBC Statement interface.
package com.javaguides.jdbc.statement.examples;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
/**
* Select Statement JDBC Example
* @author Ramesh Fadatare
*
*/
public class SelectStatementExample {
private static final String QUERY = "select id,name,email,country,password from Users";
public static void main(String[] args) {
// using try-with-resources to avoid closing resources (boilerplate code)
// Step 1: Establishing a Connection
try (Connection connection = DriverManager
.getConnection("jdbc:mysql://localhost:3306/mysql_database?useSSL=false", "root", "root");
// Step 2:Create a statement using connection object
Statement stmt = connection.createStatement();
// Step 3: Execute the query or update query
ResultSet rs = stmt.executeQuery(QUERY)) {
// Step 4: Process the ResultSet object.
while (rs.next()) {
int id = rs.getInt("id");
String name = rs.getString("name");
String email = rs.getString("email");
String country = rs.getString("country");
String password = rs.getString("password");
System.out.println(id + "," + name + "," + email + "," + country + "," + password);
}
} catch (SQLException e) {
printSQLException(e);
}
// Step 4: try-with-resource statement will auto close the connection.
}
public static void printSQLException(SQLException ex) {
for (Throwable e: ex) {
if (e instanceof SQLException) {
e.printStackTrace(System.err);
System.err.println("SQLState: " + ((SQLException) e).getSQLState());
System.err.println("Error Code: " + ((SQLException) e).getErrorCode());
System.err.println("Message: " + e.getMessage());
Throwable t = ex.getCause();
while (t != null) {
System.out.println("Cause: " + t);
t = t.getCause();
}
}
}
}
}
Output:
1,Ram,tony@gmail.com,US,secret
3,Pramod,pramod@gmail.com,India,123
4,Deepa,deepa@gmail.com,India,123
5,Tom,top@gmail.com,India,123
Reference
https://www.javaguides.net/2018/10/jdbc-statement-interface.html
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