用Java语句创建订单表，用户表，价格表和管理员表，并且表与表之间建立连接，实现增删改查要有触发器

好的，下面是一个示例代码，可以创建这些表并建立连接，并实现增删改查以及触发器：

// 导入所需的包
import java.sql.*;

public class CreateTable {
    public static void main(String[] args) throws Exception {
        // 数据库连接信息
        String url = "jdbc:mysql://localhost:3306/mydatabase";
        String username = "root";
        String password = "root";

        // 建立连接
        Connection conn = DriverManager.getConnection(url, username, password);

        // 创建用户表
        String sql1 = "CREATE TABLE users (" +
                "id INT NOT NULL AUTO_INCREMENT," +
                "username VARCHAR(50) NOT NULL," +
                "password VARCHAR(50) NOT NULL," +
                "PRIMARY KEY (id)" +
                ")";
        PreparedStatement stmt1 = conn.prepareStatement(sql1);
        stmt1.executeUpdate();

        // 创建价格表
        String sql2 = "CREATE TABLE prices (" +
                "id INT NOT NULL AUTO_INCREMENT," +
                "name VARCHAR(50) NOT NULL," +
                "price DECIMAL(10,2) NOT NULL," +
                "PRIMARY KEY (id)" +
                ")";
        PreparedStatement stmt2 = conn.prepareStatement(sql2);
        stmt2.executeUpdate();

        // 创建订单表
        String sql3 = "CREATE TABLE orders (" +
                "id INT NOT NULL AUTO_INCREMENT," +
                "user_id INT NOT NULL," +
                "price_id INT NOT NULL," +
                "order_time TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP," +
                "PRIMARY KEY (id)," +
                "FOREIGN KEY (user_id) REFERENCES users(id)," +
                "FOREIGN KEY (price_id) REFERENCES prices(id)" +
                ")";
        PreparedStatement stmt3 = conn.prepareStatement(sql3);
        stmt3.executeUpdate();

        // 创建管理员表
        String sql4 = "CREATE TABLE admins (" +
                "id INT NOT NULL AUTO_INCREMENT," +
                "username VARCHAR(50) NOT NULL," +
                "password VARCHAR(50) NOT NULL," +
                "PRIMARY KEY (id)" +
                ")";
        PreparedStatement stmt4 = conn.prepareStatement(sql4);
        stmt4.executeUpdate();

        // 创建触发器，实现订单表插入数据时更新用户的余额信息
        String sql5 = "CREATE TRIGGER update_user_balance AFTER INSERT ON orders FOR EACH ROW " +
                "UPDATE users SET balance = balance - (SELECT price FROM prices WHERE id = NEW.price_id) " +
                "WHERE id = NEW.user_id";
        PreparedStatement stmt5 = conn.prepareStatement(sql5);
        stmt5.executeUpdate();

        // 插入一些示例数据
        String sql6 = "INSERT INTO users (username, password) VALUES ('user1', 'password1')";
        PreparedStatement stmt6 = conn.prepareStatement(sql6);
        stmt6.executeUpdate();

        String sql7 = "INSERT INTO prices (name, price) VALUES ('product1', 10.00)";
        PreparedStatement stmt7 = conn.prepareStatement(sql7);
        stmt7.executeUpdate();

        String sql8 = "INSERT INTO orders (user_id, price_id) VALUES (1, 1)";
        PreparedStatement stmt8 = conn.prepareStatement(sql8);
        stmt8.executeUpdate();

        // 查询示例数据
        String sql9 = "SELECT * FROM users";
        PreparedStatement stmt9 = conn.prepareStatement(sql9);
        ResultSet rs1 = stmt9.executeQuery();
        while (rs1.next()) {
            System.out.println("id: " + rs1.getInt("id") + ", username: " + rs1.getString("username") + ", password: " + rs1.getString("password"));
        }

        String sql10 = "SELECT * FROM prices";
        PreparedStatement stmt10 = conn.prepareStatement(sql10);
        ResultSet rs2 = stmt10.executeQuery();
        while (rs2.next()) {
            System.out.println("id: " + rs2.getInt("id") + ", name: " + rs2.getString("name") + ", price: " + rs2.getDouble("price"));
        }

        String sql11 = "SELECT * FROM orders";
        PreparedStatement stmt11 = conn.prepareStatement(sql11);
        ResultSet rs3 = stmt11.executeQuery();
        while (rs3.next()) {
            System.out.println("id: " + rs3.getInt("id") + ", user_id: " + rs3.getInt("user_id") + ", price_id: " + rs3.getInt("price_id") + ", order_time: " + rs3.getTimestamp("order_time"));
        }

        // 更新示例数据
        String sql12 = "UPDATE users SET password = 'newpassword' WHERE id = 1";
        PreparedStatement stmt12 = conn.prepareStatement(sql12);
        stmt12.executeUpdate();

        // 删除示例数据
        String sql13 = "DELETE FROM orders WHERE id = 1";
        PreparedStatement stmt13 = conn.prepareStatement(sql13);
        stmt13.executeUpdate();

        // 关闭连接
        conn.close();
    }
}

这段代码可以创建四个表，并且实现了增删改查以及一个触发器，当订单表插入数据时自动更新用户的余额信息。

希望这能对您有所帮助！