回溯建库中的主题标引具有一般主题标引的共性外 ,还具有其独特的个性。这是因为回溯建库中的主题标引的主要依据是馆藏卡片目录 ,而非原始文献 ,这必然增加了主题分析的难度 ,容易造成主题标引的误标和漏标。同时在回溯建库过程中普遍存在着利用外来数据的问题 ,外来数据中的 The indexing in the backtracking database has the commonness of general theme indexing as well as its unique personality. This is because the main basis of the subject index in the retrospective building database is the contents of the card catalog instead of the original documents, which inevitably increases the difficulty of theme analysis and easily leads to false labeling and missed labeling of the topic indexing. In the meantime, the problem of using foreign data is ubiquitous in the process of backtracking and building database. In foreign data