What are computer retrieval technologies?

Computer retrieval technology: 1. Boolean logic retrieval is to use Boolean logic operators to logically combine search words or codes. 2. Truncation search. 3. Positional retrieval is to use the natural language in the record to search. The logical relationship between words is combined with positional operators to limit the relative positions between search terms. 4. Field-limited search refers to a search method that limits the search terms to search within one or several fields in the database record. 5. Weighted retrieval is a quantitative retrieval technology. 6. Cluster search.

The operating environment of this tutorial: Windows 7 system, Dell G3 computer.

Computer retrieval means that people use specific search instructions, search words and search strategies on computers or computer search network terminals to retrieve the required information from the database of the computer retrieval system, and then use the terminal The process by which a device displays or prints.

In computer information retrieval systems, there are six commonly used retrieval technologies:

1. Boolean logic retrieval

Use Boolean logic calculations It is the most commonly used technology in modern information retrieval systems to carry out logical combination of search words or codes. There are three commonly used Boolean logic operators, namely logical OR (OR), logical AND (AND), and logical NOT (NOT).

2. Truncated word retrieval

Truncated word retrieval is a very commonly used technology in computer retrieval systems. Due to the word-formation characteristics of Western languages, we often encounter inconsistent singular and plural forms of nouns in searches; English and American spellings of words with the same meaning are inconsistent; adding prefixes and suffixes of different natures to the stem can derive many words with similar meanings. words and so on. This requires the use of truncation search.

3. Position search

Position search is also called full-text search and proximity search. The so-called full-text search is to use the natural language in the record to search. The logical relationship between words is combined with position operators to limit the relative positions between search terms. This is a technical method that can directly use free words to search without relying on subject thesaurus.

4. Field-limited retrieval

Field-limited retrieval refers to a search method that limits the search terms to search within one or several fields in the database record. In the retrieval system, there are usually two types of searchable fields set in the database: basic fields that express the subject content characteristics of the document and auxiliary fields that express the external characteristics of the document.

5. Weighted retrieval

Weighted retrieval is a quantitative retrieval technology provided in some retrieval systems. Weighted retrieval, like Boolean retrieval and truncation retrieval, is also a basic search method for document retrieval. However, unlike them, weighted retrieval does not focus on determining whether the search term or string exists in the database or is different from other search terms. What is the relationship between the search words or strings, but it is about determining the impact of the search words or strings on whether the document is hit or not after satisfying the search logic.

6. Clustering retrieval

Clustering is to classify unclassified things without knowing how many categories they should be classified into. Based on the different intrinsic attributes of things, information with similar attributes is classified under the same category.

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