Kode Java

 
package org.kodejava.example.sql;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
 
import java.util.ArrayList;
 
public class MetadataColumnExample {
    private static final String DRIVER = "com.mysql.jdbc.Driver";
    private static final String URL = "jdbc:mysql://localhost/testdb";
    private static final String USERNAME = "root";
    private static final String PASSWORD = "";
    
    public static void main(String[] args) throws Exception {
	Connection connection = null;
	try {
	    //
	    // As the usual ritual, load the driver class and get connection
	    // from database.
	    //
	    Class.forName(DRIVER);	    
	    connection = DriverManager.getConnection(URL, USERNAME, PASSWORD);
	    
	    //
	    // In the statement below we'll select all records from users table
	    // and then try to find all the columns it has.
	    //
	    Statement statement = connection.createStatement();
	    ResultSet resultSet = statement.executeQuery("SELECT * FROM users");
	    
	    //
	    // The ResultSetMetaData is where all metadata related information
	    // for a result set is stored.
	    //
	    ResultSetMetaData metadata = resultSet.getMetaData();
	    int columnCount = metadata.getColumnCount();
	    
	    // 
	    // To get the column names we do a loop for a number of column count
	    // returned above. And please remember a JDBC operation is 1-indexed
	    // so every index begin from 1 not 0 as in array.
	    //
	    ArrayList<String> columns = new ArrayList<String>();
	    for (int i = 1; i < columnCount; i++) {
		String columnName = metadata.getColumnName(i);
		columns.add(columnName);
	    }
	    	    
	    //
	    // Later we use the collected column names to get the value of the
	    // column it self.
	    //
	    while (resultSet.next()) {
		for (String columnName : columns) {
		    String value = resultSet.getString(columnName);
		    System.out.println(columnName + " = " + value);
		}
	    }
	    
	} catch (SQLException e) {
	    e.printStackTrace();
	} finally {
	    connection.close();
	}
    }
}
 
 

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