Hi
Dne Fri, 05 Jun 2009 05:32:02 -0400 Marc Delisle marc@infomarc.info napsal(a):
Yes there are downsides for each alternative. Another downside for the EAV model is that at user login (session initialization) we need to read all the rows holding the user prefs for this user, instead of just one read if each option has its own column.
With index on login name, selecting several rows should be quite cheap.
As mentionned in one of the links I gave, the EAV model also makes it difficult to code the possible choices for an option, for example into an ENUM.
Okay, I probably can live with either of solutions. Both have downsides and advantages.
About upgrading, I expect Zeeshan to implement a feature to auto-create and auto-upgrade the table (which could be extended to all of our pmadb tables).
It should be coded with this in mind.