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  • Java_JDBC一般写法

    JDBC是Java DataBase Connectivity,Java程序访问数据库的标准接口。

    如果是maven工程先加入依赖的jar包:

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.35</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.35</version>
    </dependency>

    Statement

    String url = "jdbc:mysql://localhost:3306/test_db";
    String userName = "root";
    String password = "123";
    try(Connection conn = DriverManager.getConnection(url, userName,password)) {
        try(Statment sm = conn.createStatement()) {
        String name = "小明";
            try (ResultSet sm = ps.excuteQuery("SELECT * FROM test_table WHERE name='"+  +"'")) {
                while (rs.next()) {
                    System.out.println(rs.getString("name"));
                }
            }
        }
    }

    PreparedStatement

    1.查询

    String url = "jdbc:mysql://localhost:3306/test_db";
    String userName = "root";
    String password = "123";
    try(Connection conn = DriverManager.getConnection(url, userName,password)) {
        try(PreparedStatment ps = conn.preparedStatement("SELECT * FROM test_table WHERE name=?")) {
            ps.setObject(1, "rick");
            try (ResultSet rs = ps.excuteQuery()) {
                while (rs.next()) {
                    System.out.println(rs.getString("name"));
                }
            }
        }
    }

    2.新增、更新、删除

    String url = "jdbc:mysql://localhost:3306/test_db";
    String userName = "root";
    String password = "123";
    try(Connection conn = DriverManager.getConnection(url, userName,password)) {
        try(PreparedStatment ps = conn.preparedStatement("UPDATE test_table SET age = ? WHERE name=?")) {
            ps.setObject(2, "rick");
            ps.setInt(1, 18);
            int n = ps.excuteQuery(); //成功执行的数据条数
        }
    }
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  • 原文地址:https://www.cnblogs.com/amiezhang/p/9570966.html
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