MySQL时间类型与Java日期时间类对应关系示例详解

try (ResultSet rs = stmt.executeQuery("SELECT * FROM time_table")) {
    while (rs.next()) {
        LocalDate date = rs.getObject("date_column", LocalDate.class);
        LocalTime time = rs.getObject("time_column", LocalTime.class);
        LocalDateTime dateTime = rs.getObject("datetime_column", LocalDateTime.class);
        Instant timestamp = rs.getObject("ts_column", Instant.class);
    }
}

PreparedStatement ps = conn.prepareStatement(
    "INSERT INTO time_table (date_column, time_column, datetime_column, ts_column) " +
    "VALUES (?, ?, ?, ?)");
    
ps.setObject(1, LocalDate.now());
ps.setObject(2, LocalTime.now());
ps.setObject(3, LocalDateTime.now());
ps.setObject(4, Instant.now());

ps.executeUpdate();

// Java 端处理微秒（MySQL DATETIME(6)）
LocalDateTime ldt = LocalDateTime.now()
    .withNano(456000000); // 456毫秒

// MySQL 创建表
CREATE TABLE events (
    event_time DATETIME(6) // 支持微秒级精度
);

// 写入统一使用 UTC 时间
ps.setObject(4, Instant.now()); // UTC 时间戳

// 读取时转换为本地时间
Instant dbTime = rs.getObject("event_time", Instant.class);
ZonedDateTime localTime = dbTime.atZone(ZoneId.systemDefault());

-- 检查时区设置
SELECT @@global.time_zone, @@session.time_zone;

-- 推荐设置为 UTC
SET GLOBAL time_zone = '+00:00';

LocalDate start = LocalDate.of(2023, 1, 1);
LocalDate end = LocalDate.of(2023, 12, 31);

PreparedStatement ps = conn.prepareStatement(
    "SELECT * FROM orders WHERE order_date BETWEEN ? AND ?");
    
ps.setObject(1, start);
ps.setObject(2, end);

Instant startInstant = ZonedDateTime.of(
    2023, 5, 1, 0, 0, 0, 0, 
    ZoneId.of("Asia/Shanghai")).toInstant();

PreparedStatement ps = conn.prepareStatement(
    "SELECT * FROM transactions WHERE create_time >= ?");
    
ps.setObject(1, startInstant);

LocalDateTime orderTime = rs.getObject("order_time", LocalDateTime.class);
LocalDateTime deliveryTime = rs.getObject("delivery_time", LocalDateTime.class);

Duration interval = Duration.between(orderTime, deliveryTime);
System.out.printf("配送耗时: %.1f小时", interval.toMinutes() / 60.0);

// 传统转现代
Timestamp ts = rs.getTimestamp("create_time");
LocalDateTime ldt = ts.toLocalDateTime();

// 现代转传统
LocalDateTime now = LocalDateTime.now();
Timestamp ts = Timestamp.valueOf(now);

graph LR
    A[业务系统时间\nLocalDateTime] -->|应用时区| B[JVM 默认时区]
    B -->|转换为UTC| C[Instant/UTC时间]
    C -->|存储至MySQL| D[TIMESTAMP列]
    D -->|读取为Instant| E[Java Instant类型]
    E -->|转换至目标时区| F[用户时区显示]