On 09/19/17 20:45, Magnus Johansson wrote:
-----Original Message-----
From: Alex Peshkoff via Firebird-devel [mailto:firebird-
de...@lists.sourceforge.net]
Sent: Tuesday, September 19, 2017 10:19 AM
I'm curious about why there is no index on SEC$USERS.SEC$USER_NAME (*)
You are right - because it's virtual table.
Thanks for confirming, as expected although not what I had hoped for.
Having database with a couple of thousand users it doesn't feels optimized
doing a natural scan every time I want to look up a user.
The only excuse for us is that before SEC$USERS table arrived one could
have no access from SQL to actual user's list at all (RDB$USERS table
even if present in regular database has nothing to do with actual users
list). I suppose optimizer can in theory use hash joins here but not
sure does it do so in current code.
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