Technical Information

How the Archives work

Understanding some key terms and the way archives are structured will help you understand how things work. You may find it more appropriate to read this section once you have done some archiving and have something to look at on your computer.

E-Rkive archives consist of a number of files. The main file, commonly referred to as the archive database, is always located in a folder called Archive and is always called EmailArchive.ekdb. The archive database is the central data file, E-Rkive cannot function without it.

When messages are archived, all text (sender, sender email, recipients, recipient emails, subject, body etc) is extracted from the message and stored in this database. The message itself is exported out of Outlook to a .msg format file which is then stored in a message data file (sort of like a mini-pst).

There can be 9,999 message data files. Only 500 messages are stored in each message data file so as one becomes full, a new one is automatically created. These message data files are stored in a folder called Archive\Messages. As the limit of message data files is set to 9,999, this means you can only ever archive 4,999,500 messages into one Archive.

NOTE: Please note that this is the count of messages archived over time and not the number of messages currently present in an Archive. If you archive 500 messages and delete 200 messages, the count still stands at 500, not 300.

The message data files are only ever used when you want to open a message or restore it back into Outlook. Viewing message lists and searching is all done using the archive database file only.

The size of the archive database file in relation to the total archive size depends on how many messages contain attachments and what the size of those attachments are (total archive = archive database + all message data files). Typically you could expect the archive database file to be between 5% and 15% of the total archive size when you have a good mix of text only messages and ones with attachments.

Consider the following scenarios to see how the total archive size is determined and how greatly it can differ.

Scenario 1 - Text only messages

Lets say you archive 500 messages which only contain text and are about 1kb in size. The text stored in the archive database will consume about as much space as the .msg file does in the message data file (which is 1kb also).

Archive database size = 500kb
Message data file size = 500kb
Total Archive size = 1000kb (1mb)

The archive database represents 50% of the total archive size

Scenario 2 - messages with attachments

OK, now imagine we have the same messages from scenario 1 but this time each message contains a 2mb jpg format photo. The data stored in the archive database is the same apart from the name of the attachment and would be still around 1kb per message. The message data file on the other hand would contain 500 x 2mb message files.

Archive database size = 500kb
Message data file size = 1000mb (1gb)
Total Archive size = 1000mb (1gb)

The archive database represents less than 1% of the total archive size

Now because E-Rkive only uses the archive database for listing messages and searching etc, the performance difference of the archive database between the two scenarios is ZERO.