import java.sql.*;
public class mysql {
public static String url = "jdbc:mysql://localhost:3306/test";//characterEncoding=GBK
public static String username = "root";
public static String password = "root";
public static Connection con;
public static Statement stmt;
public static ResultSet rs;
public static void main(String[] args) throws SQLException {
connect();
operation();
stmt.close();
con.close();
}
public static void test() {
String sql_select = "select * from tablename where id=1";
String sql_insert = "insert into tablename (col1,col2..) values('1','2'...)";
String sql_update = "update tablename set colname='update' where id=1";
//insert(sql_insert);
//select(sql_select);
//update(sql_update);
}
public static void connect() {
// 定位驱动
try {
Class.forName("com.mysql.jdbc.Driver");
System.out.println("加载驱动成功!");
} catch (ClassNotFoundException e) {
System.out.println("加载驱动失败!");
e.printStackTrace();
}
// 建立连接
try {
con = DriverManager.getConnection(url, username, password);
stmt = con.createStatement();
System.out.println("数据库连接成功!");
} catch(SQLException e) {
System.out.println("数据库连接失败!");
}
}
public static void select(String sql) {
try {
rs = stmt.executeQuery(sql);
ResultSetMetaData meta_data = rs.getMetaData();//列名
for (int i_col = 1; i_col <= meta_data.getColumnCount(); i_col++) {
System.out.print(meta_data.getColumnLabel(i_col) + " ");
}
System.out.println();
while (rs.next()) {
for (int i_col = 1; i_col <= meta_data.getColumnCount(); i_col++) {
System.out.print(rs.getString(i_col) + " ");
}
System.out.println();
}
rs.close();
}catch (Exception e) {
System.out.println("数据查询失败!");
}
}
public static void insert(String sql) {
try {
stmt.clearBatch();
stmt.addBatch(sql);
stmt.executeBatch();
System.out.println("数据插入成功!");
}catch (Exception e) {
System.out.println("数据插入失败!");
}
}
public static void update(String sql) {
try {
stmt.executeUpdate(sql);
System.out.println("数据更新成功!");
}catch (Exception e) {
System.out.println("数据更新失败!");
}
}
}
