jTDS当前不支持SQL Server 2008中引入的datetimeoffset
数据类型。
有人可以建议是否可以通过jTDS使用datetimeoffset
类型吗?
最佳答案
如datetimeoffset documentation的“下级客户端的向后兼容性”部分所述,我们可以使用datetimeoffset
值的字符串表示形式。实际上,如果使用jTDS 1.3.1检索datetimeoffset
值,我们将获得以下形式的java.lang.String
值:
YYYY-MM-DD hh:mm:ss[.nnnnnnn] {+|-}hh:mm
可以这样解析这样的值:
// rs is our ResultSet object
String valueRetrieved = rs.getString(1); // e.g., "2016-12-08 12:34:56.7850000 -07:00"
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.SSSSSSS ZZZZZ");
ZonedDateTime zdt = ZonedDateTime.parse(valueRetrieved, dtf);
至于将
datetimeoffset
值写入SQL Server,jTDS无法使用.setTimestamp
正确处理更新,例如在我的机器上...java.sql.Timestamp ts = java.sql.Timestamp.valueOf("2016-12-08 12:34:56.785"); // local
String tsString = formatTimestampForDateTimeOffset(ts); // (see below)
System.out.printf(" java.sql.TimeStamp value: %s (%d ms since epoch)%n", tsString, ts.getTime());
System.out.println();
System.out.println("Saving via setTimestamp ...");
String sqlUpdate = "UPDATE dtoTable SET dtoCol = ? WHERE id=1";
try (PreparedStatement s = conn.prepareStatement(sqlUpdate)) {
s.setTimestamp(1, ts); // pass the Timestamp itself
s.executeUpdate();
}
String valueRetrieved;
try (
Statement s = conn.createStatement();
ResultSet rs = s.executeQuery("SELECT dtoCol FROM dtoTable WHERE id=1")) {
rs.next();
valueRetrieved = rs.getString(1);
System.out.printf(" jTDS saved the TimeStamp value as: %s%n", valueRetrieved);
}
...产生...
java.sql.TimeStamp value: 2016-12-08 12:34:56.785 -07:00 (1481225696785 ms since epoch)
Saving via setTimestamp ...
jTDS saved the TimeStamp value as: 2016-12-08 12:34:56.7870000 +00:00
...不仅将时区偏移错误地设置为+00:00(而不更改日期/时间值本身),而且还增加了几毫秒的娱乐时间。
但是,如果我们将Timestamp值转换为格式正确的字符串,例如...
public static String formatTimestampForDateTimeOffset(java.sql.Timestamp ts) {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS ZZZZZ");
String s = sdf.format(new Date(ts.getTime()));
// T-SQL *requires* the colon in the timezone offset: -07:00, not -0700
int colonPosition = s.length() - 2;
return s.substring(0, colonPosition) + ":" + s.substring(colonPosition);
}
...,并使用
.setString
而不是.setTimestamp
,则正确保存了datetimeoffset
值:Saving via setString ...
jTDS saved the formatted String as: 2016-12-08 12:34:56.7850000 -07:00
parsed to ZonedDateTime: 2016-12-08T12:34:56.785-07:00
converted to Instant: 2016-12-08T19:34:56.785Z
converted to java.util.Date: Thu Dec 08 12:34:56 MST 2016
关于sql-server - 在jTDS中使用datetimeoffset数据类型,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/36405320/