| | |
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| | | } |
|---|
| | | } |
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| | | |
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| | | public static Double getTotal(String tableName) { |
|---|
| | | // 1. 创建SQLite数据库连接 |
|---|
| | | try (Connection conn = DriverManager.getConnection("jdbc:sqlite:rainfall.db")) { |
|---|
| | | if (conn != null) { |
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| | | // 2. 执行SQL查询 |
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| | | String queryDataSql = "select sum(rainfall_difference) as total from(SELECT ABS( (SELECT rainfall FROM " + tableName + " WHERE station_name = s.station_name ORDER BY datetime ASC LIMIT 1) - (SELECT rainfall FROM " + tableName + " WHERE station_name = s.station_name ORDER BY datetime DESC LIMIT 1)) AS rainfall_difference FROM " + tableName + " s GROUP BY station_name)"; |
|---|
| | | // 3. 处理查询结果 |
|---|
| | | try (PreparedStatement pstmt = conn.prepareStatement(queryDataSql)) { |
|---|
| | | ResultSet rs = pstmt.executeQuery(); |
|---|
| | | while (rs.next()) { |
|---|
| | | // 获取总和 |
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| | | return rs.getDouble("total"); |
|---|
| | | } |
|---|
| | | } catch (SQLException e) { |
|---|
| | | System.err.println("查询数据时出错: " + e.getMessage()); |
|---|
| | | } |
|---|
| | | } |
|---|
| | | } catch (SQLException e) { |
|---|
| | | System.err.println("SQLite连接失败: " + e.getMessage()); |
|---|
| | | } |
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| | | |
|---|
| | | return null; |
|---|
| | | } |
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| | | |
|---|
| | | public static Integer getDuration(String tableName) { |
|---|
| | | return 1440; |
|---|
| | | } |
|---|
| | | } |
|---|
