The last access time (LastAccessTime) is an important attribute of an Object Storage Service (OSS) object. This attribute is commonly used in scenarios such as billing and object lifecycle management. After access tracking is enabled for a bucket, specific operations on an object can update the last access time of the object.
The following table describes the operations that update LastAccessTime and some of those that do not affect it.
Operation | Operation description | Impact on LastAccessTime |
CopyObject | If the source object and destination object are different, copies the source object and overwrites the destination object. | The LastAccessTime attribute of the destination object is updated, while the LastAccessTime attribute of the source object remains unchanged. |
If the source object and destination object are the same, copies the object and modifies its access control list (ACL), user metadata, storage class, and encryption type. | The LastAccessTime attribute of the object is updated. | |
PutObjectACL | Modifies the object ACL. | The LastAccessTime attribute of the object is updated. |
PutObject, PostObject, and CompleteMultipartUpload | Overwrites an existing object. | The LastAccessTime attribute of the object is updated. |
AppendObject | Appends content to an object in a versioned bucket. | The LastAccessTime attribute of the object remains unchanged. Note OSS appends new content specified in an AppendObject operation to the latest version of the object, instead of creating a separate version for the content appended by each AppendObject operation. Also note that OSS records the LastAccessTime of the first AppendObject operation on an object. Subsequent AppendObject operations on the object will not update its LastAccessTime attribute. |
Appends content to an object in a non-versioned bucket. | The LastAccessTime attribute of the object is updated. | |
GetObject | Queries an object. | The LastAccessTime attribute of the object is updated. Note When you call the GetObject operation to access an object to which a symbolic link points, the last access time of the object is also updated. |
Processes an image. | The LastAccessTime attribute of the object remains unchanged. | |
SelectObject | Performs SQL queries. | The LastAccessTime attribute of the object remains unchanged. |