Updating blob contents in sqlite

I have a few Word documents stored in sqliteblobs. From time to time the documents need updating.
Can I overwrite blob contents by writing the new contents to the blob (yes, I know you can’t resize the blob) or does the new stuff simply get added at the end of the existing contents. If not, I will have to delete the record with the current blob contents and recreate it with the new contents in the blob.
Any suggestions?

Generally in SQL databases, one update is one insert followed by one delete, so SQLite will do the “recreate” for You in any update.

update it and you should be fine