ADLS2 Blob Storage "Last Modified Date" generation timestamp

Question

I have a data integration process that brings multiple files into ADLS2 Blob.

The interesting thing found is some files that arrive late (appears later in the Blob) but has earlier Last Modified Date.

For example, File A was loaded into Blob at timestamp "10:30:00" has Last Modified Date of "10:29:55". File B was loaded into Blob at timestamp "10:30:05" has Last Modified Date of "10:29:50".

Does it indicates the Last Modified Date is generated/recorded at the "file receive timestamp" instead of the "file close timestamp"?

Answer 1

These are my observations when I tried in my environment.

You can see that even though file is started uploading on a certain time, the last modified time was taken when total file uploaded successfully.

It is the same result when modifying the file as well. The time stamp will be taken when the file is last time saved in the case of modification and uploaded time in the case of new file creation.

I checked this for various sizes of files, and all gave the same result. I suggest you recheck your total file loading time and last modified time.

If the issue still persists, then it's better to raise a Support ticket on this for deeper investigation.