用jdbc实现对数据库增删改查代码
时间: 2024-03-20 22:41:34 浏览: 16
好的,以下是使用JDBC实现数据库增删改查的示例代码:
1. 连接数据库
```
String jdbcUrl = "jdbc:mysql://localhost:3306/myDatabase";
String username = "myUsername";
String password = "myPassword";
try {
Connection connection = DriverManager.getConnection(jdbcUrl, username, password);
// 连接成功
} catch (SQLException e) {
// 连接失败
}
```
2. 插入数据
```
try {
String sql = "INSERT INTO myTable (column1, column2, column3) VALUES (?, ?, ?)";
PreparedStatement statement = connection.prepareStatement(sql);
statement.setString(1, "value1");
statement.setInt(2, 2);
statement.setDouble(3, 3.14);
int rowsInserted = statement.executeUpdate();
if (rowsInserted > 0) {
System.out.println("数据插入成功");
}
} catch (SQLException e) {
System.out.println("数据插入失败:" + e.getMessage());
}
```
3. 更新数据
```
try {
String sql = "UPDATE myTable SET column1 = ? WHERE column2 = ?";
PreparedStatement statement = connection.prepareStatement(sql);
statement.setString(1, "new value");
statement.setInt(2, 2);
int rowsUpdated = statement.executeUpdate();
if (rowsUpdated > 0) {
System.out.println("数据更新成功");
}
} catch (SQLException e) {
System.out.println("数据更新失败:" + e.getMessage());
}
```
4. 删除数据
```
try {
String sql = "DELETE FROM myTable WHERE column2 = ?";
PreparedStatement statement = connection.prepareStatement(sql);
statement.setInt(1, 2);
int rowsDeleted = statement.executeUpdate();
if (rowsDeleted > 0) {
System.out.println("数据删除成功");
}
} catch (SQLException e) {
System.out.println("数据删除失败:" + e.getMessage());
}
```
5. 查询数据
```
try {
String sql = "SELECT * FROM myTable WHERE column2 = ?";
PreparedStatement statement = connection.prepareStatement(sql);
statement.setInt(1, 2);
ResultSet resultSet = statement.executeQuery();
while (resultSet.next()) {
String column1Value = resultSet.getString("column1");
int column2Value = resultSet.getInt("column2");
double column3Value = resultSet.getDouble("column3");
System.out.println(column1Value + ", " + column2Value + ", " + column3Value);
}
} catch (SQLException e) {
System.out.println("数据查询失败:" + e.getMessage());
}
```
希望这可以帮助您使用JDBC实现数据库增删改查。