This method is undoubtedly the most time-consuming and least effective. Sequential scanning: You can also know its approximate search method through the text name, that is, query specific keywords in a sequential scanning manner.įor example, give you a newspaper and let you find where the text “RNG” appears in the newspaper . You definitely need to scan the newspaper from beginning to end, and then mark the sections where the keyword appeared and where it appeared.
There are two main methods for searching unstructured data, that is, full-text data: When required, it can be processed as structured data, or plain text can be extracted and processed as unstructured data.Īccording to two types of data classification, search is also divided into two types: structured data search and unstructured data search.įor structured data, we usually can be relational databases (MySQL , the Oracle , etc. ) of the table way to store and search can also be indexed. Of course, there will be a third type in some places: semi-structured data, such as XML , HTML, etc. Unstructured data: Unstructured data can also be called full-text data, which refers to data of indefinite length or no fixed format, such as mail, Word documents, etc. Structured data: refers to data with a fixed format or limited length, such as databases, metadata, etc. There are two types of data in our lives: For a more detailed explanation, let’s start with the data in life. Some web search engines, such as, employ full-text-search techniques, while others index only a portion of the web pages examined by their indexing systems.įrom the definition, we can roughly understand the idea of full-text retrieval. Many websites and application programs (such as word processing software) provide full-text-search capabilities. Full-text-searching techniques became common in online bibliographic databases in the 1990s. In a full-text search, a search engine examines all of the words in every stored document as it tries to match search criteria (for example, text specified by a user). Full-text search is distinguished from searches based on metadata or on parts of the original texts represented in databases (such as titles, abstracts, selected sections, or bibliographical references).
In text retrieval , full-text search refers to techniques for searching a single computer -stored document or a collection in a full-text database.
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Anytxt Searcher is a free desktop full-text search tool.
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