Mnesia, mnesia_frag, and table locks using index_match_object et al.

Ulf Wiger ulf@REDACTED
Tue Feb 28 21:04:17 CET 2006

Den 2006-02-28 06:14:00 skrev Scott Lystig Fritchie  

> For my purpose, I would like to insert a single record into the
> 'thing' table *and* guarantee that both primary_key and secondary_key
> are unique.  The former is trivial: the table type is 'set'.  I was
> hoping to do the latter by the following (simplifed!) without whole
> table locks:

I had this implemented in my previous index hack in mnesia.
I'm putting it into rdbms now. You will be able to specify
a unique index on a secondary key. It will abort if the
value is not unique to the current object.

These index tabs will also support fragmentation, and will
attempt to do index lookups on fragmented tables as
efficiently as possible (find the index fragment with the
given index value, then rpc only to the fragments with
corresponding objects.)

Ulf Wiger

More information about the erlang-questions mailing list