versionId

VersionId is a label assigned to a specific version of a resource, document, or artifact in computing systems. It serves to distinguish successive revisions, enabling history tracking, data integrity, and coordination across clients and services. The resource’s core identity often remains the same while the versionId changes with each update. In APIs and data stores, versionId can be used to implement optimistic concurrency control: a client sends the versionId it retrieved, and an update proceeds only if the current version matches, preventing lost updates.

Formats for versionId vary. They may be simple numeric counters, semantic version strings (for example, 2.1.0), timestamps (such as 2024-12-31T23:59:59Z), or opaque identifiers like UUIDs. Some systems store versionId in a dedicated field, others expose it in headers or as part of a resource URL. A versionId is typically distinct from the resourceId, which identifies the object across all versions.

In practical use, versionId supports features such as historical queries, rollback, synchronization, and cache invalidation. It is often used alongside metadata like lastModified timestamps or HTTP ETags in web services to manage caching and consistency. Best practices include making version identifiers immutable once assigned, choosing a suitable format for the deployment context, and updating the versionId with each meaningful change to reflect the new state of the resource.