Using ndb in RPM (was: Re: F27 System Wide Change: RPM 4.14)

[Richard W.M. Jones]

On Fri, Jul 07, 2017 at 04:15:53PM +0200, Jaroslav Reznik wrote:
>  = System Wide Change: RPM 4.14 =
>  https://fedoraproject.org/wiki/Changes/RPM-4.14 
The web page has:

   Improvements and stabilization of "ndb" (New RPM DB Format database
   format)
...
   Changing database from bdb to ndb requires patching of some programs
   who read/expect /var/lib/rpm/Packages and other files directly
   without using librpm

which were not included in this email.

The problem is that "NDB" is a custom homebrew database invented in
the RPM codebase.  I agree that because of licensing problems we need
to move away from Berkeley DB, but why not switch to the obvious,
bulletproof choice - Sqlite?

Look at the all new nbd code here:

  https://github.com/rpm-software-management/rpm/tree/master/lib/backend/ndb

Inventing a new database including a new disk format and all new code
is bound to cause problems with database corruption, incorrect
database synchronization, incorrect handling of parallel queries, and
a rich source of other bugs for a long time.

Not to mention ‘ndb requires patching of some programs who read/expect
/var/lib/rpm/Packages and other files directly without using librpm’ -
this would still require changes, but they are much smaller if you're
using sqlite.

It was a bad upstream decision, but it's not too late to avoid it by
sticking with BDB for now and using sqlite in the long run.

Rich.

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