The full-text databases include China HowNet, VIP Information, Wanfang Database, springerlink, IEEE, OCLC, ProQuest, JSTOR, ScienceDirect, Wiley, etc.
Full-text database, that is, full-text field database, stores and organizes the information content of full-text documents according to a certain structural system and organization mode, so that users can take the content of full-text documents as the retrieval entrance and obtain more detailed document information.
Development steps
The development steps of full-text database include data preparation, text preprocessing, data loading, data retrieval and data maintenance.
① Data preparation refers to the pretreatment process of collecting, sorting and classifying the data to be loaded into the full-text database. There are many ways to get the data loaded into the full-text database. Common data sources are: files generated by computer typing, manuscripts generated by electronic printing, files transmitted by computers on the Internet, electronic publications, files generated by graphic processing, and specially organized manual input to establish a database.
After data collection, we should do some simple classification. Generally, it is classified according to data content, and similar content is loaded into the same library, which is easy to find. Classification is more effective for big data.
② Text preprocessing includes standard format and index. When there are various document formats, they should be sorted out and standardized. The batch index completed in this preprocessing stage is not limited by the structure of the full-text database and has high efficiency. Before the full-text database is established, the data are indexed by word processing software and special automatic indexing software.
There are several ways to establish an indexing thesaurus, which can be compiled by the system builder after browsing the text, or by the editor after adding special symbols to the words in the text through the computer, collecting, merging, sorting out and eliminating duplication through special software, or adding attribute indexing on the basis of the above.
③ After the data is ready, it can be loaded (copied and input) into the database file. Data can be loaded in a single project or in batches. One article at a time, loaded in a single way, suitable for loading documents at any time; Batch mode loads multiple projects at one time, which is suitable for centralized loading.
(4) After the database is established, it can be retrieved according to the retrieval function provided by the full-text retrieval system.
⑤ After the full-text database is established, the contents of the database need to be indexed, updated, appended and sorted frequently to ensure the practicability, effectiveness and integrity of the database. The maintenance of full-text database usually includes: the structure definition of full-text database, the data content of full-text database, the vocabulary used by full-text system, and the utilization statistics and adjustment of storage space.