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[EP-tech] Re: Adding fields to a live system - any data integrity concerns?


If you want to do it as a hotfix, the proper procedure would be to
1. Add expected columns and indexes to database tables
2. Add the field definition (which depends on 1)
3. (optional) Run whatever initialization scripts you need to run for
the field
4. apachectl graceful

Unfortunately, EPrints tools assume that you add the field definition
first and that they then update the database for you. This leaves a
window of inconsistency during which your users will get errors.

Obviously, if you don't mind a short service interruption, it's not a
concern and you can do it "offline" during a maintenance window:
1. apachectl stop
2. Add field definition
3. Use epadmin to update database
4. (optional) Run whatever initialization scripts you need to run for
the field
5. apachectl start

On 07/18/2014 02:58 PM, Andrew Beeken wrote:
> Hello all! I’ve just added a new field to our test EPrints and am ready to put it live. Obviously I understand how to do this from the command line, but my concerns are around any precautions that should be taken when doing this on a live system. I’m arranging for the server to be backed up as a precaution, however should it also be taken offline while the database is rewritten?
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