This article aims to provide an objective comparison between the Datetime and Timestamp data types in BigQuery.

The Datetime data type represents civil time and lacks timezone information, whereas the Timestamp data type refers to an absolute point in time and incorporates timezone details.

The primary distinction lies in their representation of time, with Datetime representing the civil time observed on a watch or calendar, and Timestamp representing an absolute point in time, including timezone information.

While Datetime is seldom used and typically employed to represent a specific date and time without timezone, Timestamp is the preferred data type in most cases.

BigQuery interprets timezone information for Timestamp and internally represents it as a UTC timestamp.

By understanding the differences and usage scenarios of these data types, users can make informed decisions when working with temporal data in BigQuery.

What is it?

The difference between Datetime and Timestamp in BigQuery lies in their representation of time.

Datetime represents the civil time seen on a watch or calendar. It does not refer to an absolute instance in time and does not have timezone information. It is typically used to represent a specific date and time without timezone.

Timestamp, on the other hand, refers to an absolute point in time and is internally represented as a UTC timestamp. It includes timezone information and allows for the interpretation of timezone information. It is the preferred data type in most cases.

BigQuery stores Timestamp internally as a UTC timestamp, ensuring consistency in its representation of time.

Differences and Usage

Differences between the two data types can be observed in their representation of time.

• datetime represents the civil time seen on a watch or calendar.
• timestamp represents an absolute point in time, including timezone information.

Datetime does not have timezone information and is often used to represent a specific date and time without considering the timezone.

On the other hand, timestamp is the preferred data type in most cases as it stores an absolute point in time and internally represents it as a UTC timestamp.

BigQuery interprets timezone information for timestamp and represents it as a UTC timestamp.

Therefore, the choice between datetime and timestamp depends on the need for timezone information and the specific use case.

Representation of time

One important aspect to consider when discussing the representation of time in these two data types is their handling of timezone information.

Datetime does not include timezone information and represents the civil time seen on a watch or calendar. It is typically used to represent a specific date and time without any reference to a particular timezone.

On the other hand, Timestamp includes timezone information and represents an absolute point in time. It is internally stored as a UTC timestamp and BigQuery interprets the timezone information accordingly.

This makes Timestamp the preferred data type in most cases, especially when dealing with time-sensitive data that requires accurate representation of time in different timezones.

Overall, the difference in representation of time between Datetime and Timestamp lies in the inclusion or exclusion of timezone information.