OCP-1Z0-053-V12.02-463题

463.Which of the following datatypes store time-zone information in the database?

A. TIMESTAMP

B. DATE

C. TIMESTAMP WITH TIME ZONE

D. TIMESTAMP WITH LOCAL TIME ZONE

E. DATETIME

Answer: C

答案解析:

参考:http://docs.oracle.com/cd/E11882_01/server.112/e41084/sql_elements001.htm#SQLRF00205


TIMESTAMP WITH TIME ZONE Data Type

TIMESTAMP WITH TIME ZONE is a variant of TIMESTAMP that includes a time zone region name or a time zone offset in its value. The time zone offset is the difference (in hours and minutes) between local time and UTC (Coordinated Universal Time—formerly Greenwich Mean Time). This data type is useful for preserving local time zone information.

Specify the TIMESTAMP WITH TIME ZONE data type as follows:

TIMESTAMP [(fractional_seconds_precision)] WITH TIME ZONE

where fractional_seconds_precision optionally specifies the number of digits Oracle stores in the fractional part of the SECOND datetime field. When you create a column of this data type, the value can be a number in the range 0 to 9. The default is 6.

Oracle time zone data is derived from the public domain information available at http://www.iana.org/time-zones/. Oracle time zone data may not reflect the most recent data available at this site.


 

TIMESTAMP WITH LOCAL TIME ZONE Data Type

TIMESTAMP WITH LOCAL TIME ZONE is another variant of TIMESTAMP that is sensitive to time zone information. It differs from TIMESTAMP WITH TIME ZONE in that data stored in the database is normalized to the database time zone, and the time zone information is not stored as part of the column data. When a user retrieves the data, Oracle returns it in the user's local session time zone. This data type is useful for date information that is always to be displayed in the time zone of the client system in a two-tier application.

Specify the TIMESTAMP WITH LOCAL TIME ZONE data type as follows:

TIMESTAMP [(fractional_seconds_precision)] WITH LOCAL TIME ZONE

where fractional_seconds_precision optionally specifies the number of digits Oracle stores in the fractional part of the SECOND datetime field. When you create a column of this data type, the value can be a number in the range 0 to 9. The default is 6.

Oracle time zone data is derived from the public domain information available at http://www.iana.org/time-zones/. Oracle time zone data may not reflect the most recent data available at this site.


 
原文地址:https://www.cnblogs.com/hzcya1995/p/13316364.html