JDBC

Driver

DriverManager.registerDriver(new org.postgresql.Driver());
Class.forName("org.postgresql.Driver");

Connection

NO	方法	描述
1	Statement createStatement()	创建 Statement 对象
2	PreparedStatement prepareStatement(String sql)	预编译 sql 的 Statement 对象
3	CallableStatement prepareCall(String sql)	执行存储过程的 Statement
4	void setAutoCommit(boolean autoCommit)	事务自动提交
5	void commit()	提交事务
6	void rollback()	回滚事务

Connection connection = DriverManager.getConnection(url, user, password);
Statement statement = connection.createStatement();

Statement

NO	方法	描述
1	ResultSet executeQuery(String sql)	查询
2	int executeUpdate(String sql)	增删改
3	boolean execute(String sql)	任意SQL
4	void addBatch(String sql)	批处理
5	int[] executeBatch()	批处理执行

ResultSet resultSet = statement.executeQuery(sql);

预编译 SQL 解决注入问题

String sql = "SELECT * FROM y_production_order WHERE order_code = ?";
PreparedStatement statement = connection.prepareStatement(sql);
statement.setString(1, "RBJ3086B1023");
ResultSet resultSet = statement.executeQuery();

ResultSet

NO	方法	描述
1	Object getObject(String columnLabel)	获取任意类型的数据
2	String getString(String columnLabel)	获取指定类型的数据
3	boolean next()
4	boolean previous()
5	boolean absolute(int row)
6	void beforeFirst()
7	void afterLast()

while (resultSet.next()) {
    String order_no  = resultSet.getString("order_no");
    System.out.println("order_no: " + order_no);
}