java增删改查怎么写
时间: 2023-11-11 10:13:44 浏览: 26
对于您的第一个问题,我可以给您提供一些基本的Java操作示例:
1. 增加数据:
```
// 插入数据 INSERT INTO table_name (column1, column2, column3, ...) VALUES (value1, value2, value3, ...);
String sql = "INSERT INTO user (name, age, gender) VALUES ('Tom', 18, 'male')";
stmt.executeUpdate(sql); //stmt 是声明的 Statement 对象
```
2. 删除数据:
```
// 删除数据 DELETE FROM table_name WHERE condition;
String sql = "DELETE FROM user WHERE id = 1";
stmt.executeUpdate(sql);
```
3. 修改数据:
```
// 修改数据 UPDATE table_name SET column1 = value1, column2 = value2, ... WHERE condition;
String sql = "UPDATE user SET age = 20 WHERE id = 1";
stmt.executeUpdate(sql);
```
4. 查询数据:
```
// 查询数据 SELECT column1, column2, ... FROM table_name WHERE condition;
String sql = "SELECT * FROM user WHERE id = 1";
ResultSet rs = stmt.executeQuery(sql); // rs 是查询结果集对象
while(rs.next()) {
String name = rs.getString("name");
int age = rs.getInt("age");
String gender = rs.getString("gender");
System.out.println("Name: " + name + ", Age: " + age + ", Gender: " + gender);
}
```
希望以上示例能够对您有所帮助!