Why is the Timestamp function useful when creating unique keys?

The Timestamp function is particularly useful when creating unique keys because it provides a constantly changing value that is unique to each row. This feature ensures that every entry in a dataset can be distinguished from all others based on the specific time at which it was created or updated. This is important in environments where multiple records might be created in rapid succession, as each record can be assigned a unique key based on the exact timestamp down to milliseconds.

Using a timestamp allows for accurate tracking and auditing, especially in cases where data integrity and uniqueness are critical. This functionality is beneficial in a variety of applications, such as inventory management or transaction processing, where it is necessary to have a precise sequence of events without the risk of duplication in keys.

The other options do not align with the primary utility of the Timestamp function in this context. For example, generating the same value for all records would defeat the purpose of creating unique keys. Limiting keys to business hours could restrict data handling and management flexibility, while formatting keys in a textual representation does not inherently provide uniqueness or cater to the need for precise timestamps. Thus, using timestamps is a rational choice for ensuring each record has a distinctive identifier.