why not use ldap for users address books?

[eleith]

the main use of ldap in zimbra seems to be to store zimbra users/groups.

however, from my understanding of ldap, it can also be used to store contact information (other than a system's users contact info). if this is true, then why does zimbra not store address books using ldap instead of mysql?

does ldap lack appropriate authority/sharing mechanisms, forcing zimbra to use mysql/soap?

[dkarp]

That's part of it. Plus, if you want contacts to be taggable, flaggable, moveable, etc. they really should be stored in the same data store as everything else that's taggable, flaggable, moveable, etc.

Another problem is that across the whole install, address books change too often -- you're bottlenecked on write throughput to the LDAP master.

[quanah]

Another problem is that across the whole install, address books change too often -- you're bottlenecked on write throughput to the LDAP master.

Actually, I personally wouldn't worry about write throughput on the LDAP master all that much. What concerns me more, is the absolute mess email clients have made of the concept of LDAP based addressbooks. They almost all want their own schema ideas in place as to how the data should be stored, which makes it virtually impossible to store the data in a way where all email clients are happy and/or know what to do with the data they get back.