关键词: 检索表, 单道检索表, 多道检索表, 根本矛盾, 主要矛盾

Abstract: Based on analysis of the structure of keys, this paper deems that the fundamental contradiction of keys is the contradiction between the individual characters of specimens and the common characters used in keys. The principal contradiction of single-access key is the contradiction between the characters used conditionally in keys and the finite characters of individual specimens, so single-access key cannot well solve the fundamental contradiction and is limited in applicative areas and on using effect. The principal contradiction of multi-access key is a contradiction between the limited characters of character database and the unlimited individual characters of species, hence there is not the contradiction between individual characters and the common characters. Therefore, multi-access key well resolves the fundamental contradiction and can be utilized expediently.

Key words: key, single-access key, multi-access key, fundamental contradiction, principal contradiction