14.03.2016 10:41, liviuslivius wrote: > Why? > Index is a Tree? And if i found VALUE 2 in A key then i can fast find > value 5 in sub key (leaf) > You scan throught keys in A, and then in finded nodes you look for leafs > in B
Compound index key is a single concatenated value, not two separate ones. You may search for exact match {2, 5} or for its "substring" {2}. You cannot get the second segment from the key as independent value. Firebird indices are imprecise and generally you may convert value->key but cannot key->value. Dmitry