createtime

Createtime refers to a timestamp marking when an entity was created. It is used to establish provenance, support auditing, enable versioning, and aid data retention. The exact meaning can vary by system, and it is not a universal standard. In many Unix-like systems, the common timestamps are atime (last access), mtime (last modification), and ctime (change). Creation time may not be available or standardized in all environments. Some filesystems, such as ext4, HFS+, and NTFS, offer a birth time or crtime, which some tools can expose, while others rely on application-managed timestamps.

In databases and application code, createtime is typically stored as a field such as created_at or creation_time. Common data types include TIMESTAMP, DATETIME, or ISO 8601 strings. Createtime is frequently indexed to accelerate queries by date and to support retention policies or audit reporting. In APIs and programming languages, createtime may be represented as a Unix epoch value (seconds or milliseconds) or as ISO 8601-formatted strings; adopting UTC and a consistent representation is recommended.

Best practices include recording createtime at the moment of creation, using a uniform time standard (preferably UTC), and treating the field as immutable when possible. It is also advisable to document the precise semantics (whether the timestamp reflects the object's birth time, an initial creation event, or a logical creation in an application) and to consider time zone normalization to ensure reliable cross-system comparisons.