We have a program that regularly generates an error when executing the
update SQL below when running overnight and its the only active
program/connection (Linux classic server LI-V2.0.1.12855 Firebird 2.0)
but always works in the day when there are multiple users accessing
the same data.

The only obvious difference is that overnight it has to clear >6000
records (out of 36000) whereas during the day the number is usually < 1000

SQL = 'UPDATE PARTS SET INMRP = 0 where INMRP <> 0 '
INMRP is defined as INTEGER DEFAULT 0 NOT NULL

Error message = 'deadlock
update conflicts with concurrent update'

The program closes all its SQL's and transactions prior to executing
this one. I trap the failure and then step through each records with
INMRP<>0 and clear them individually - which always works.

Question - is this actually a deadlock, or simply the server timing
out the SQL because of the number of records being updated ??