Hi Ann,
This is the crux of the matter
“Index entries for the old and new versions of a record all contain the DBKey
of the primary (newest) record version. When doing an indexed lookup,
Firebird walks backward through the record versions until it finds one that
the current transaction can see, then check whether the key values in that
record version match the lookup values.”

thanks you again
now i am ready to digg into FB source code – sadly i do not like C++

regards,
Karol Bieniaszewski

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