Structured, semi-structured, and unstructured

Compared with structured data (that is, row data, stored in a database, the two-dimensional table structure can be used to logically express the implemented data, data that is not convenient to use two-dimensional Logical tables in the database is called unstructured data, including all formats of office documents, text, images, XML, HTML, various reports, images and audio/video information.
An unstructured database is a database with variable field lengths and records of each field can be composed of repeated or non-repeated child fields, it not only can process structured data (such as numbers and symbols), but also is more suitable for processing unstructured data (such as full text, images, sound, film and television, and hypermedia ).
Unstructured web databases are mainly generated for unstructured data. Compared with popular relational databases, the biggest difference is that it breaks through the constraints of changing the schema definition of a relational database and setting the Data Length, supports repeated fields, subfields, and variable-length fields, and enables processing of variable-length data and repeated fields, and variable-length storage and management of data items. It processes continuous information (including full-text information) unstructured information (including various multimedia information) has incomparable advantages of traditional relational databases.
Structured Data (that is, row data, stored in a database, which can be logically expressed using a two-dimensional table structure)
Unstructured data, including all formats of office documents, text, images, XML, HTML, various reports, images and audio/video information, etc.
The so-called semi-structured data refers to data between fully structured data (such as relational databases and data in object-oriented databases) and completely unstructured data (such as sound and image files, HTML documents are semi-structured data. It is generally self-describing, and the data structure and content are mixed together without obvious distinction.
Data Model:
Structured Data: Relational Tables)
Semi-structured data: trees and Graphs
Unstructured data: None
Data Models of rmdbs include: mesh data models, hierarchical data models, and relational databases.
Others:
Structured Data: structured data and data
Semi-structured data: Data first and structured again
With the development of network technology, especially the rapid development of Internet and Intranet technology, the number of unstructured data is increasing. At this time, the limitations of relational databases that are mainly used to manage structured data are becoming more and more obvious. Therefore, the database technology entered the "post-relational database era" and evolved into the era of unstructured databases based on network applications.
China's non-structured database is represented by the iBase database of Beijing guomeibes (IBASE) software Co., Ltd. IBase is an end-user oriented unstructured database. It is internationally advanced in processing unstructured information, full-text information, multimedia information, mass information, and Internet/Intranet applications, breakthroughs have been made in the management of unstructured data and full-text retrieval. It has the following advantages:
(1) There are a large number of complex data types in Internet applications. IBASE can manage various document information and multimedia information through its external file data types, it also provides powerful full-text retrieval capabilities for various retrieval resources of document information, such as HTML, Doc, RTF, and TXT.
(2) It uses sub-fields, multi-value fields, and variable-length fields to allow the creation of many different types of unstructured or any format fields, this breaks through the very strict table structure of relational databases and enables the storage and management of unstructured data.
(3) IBASE defines unstructured and structured data as resources, so that the basic element of a non-structured database is the resource itself, and the resources in the database can contain both structured and unstructured information. Therefore, unstructured databases can store and manage a variety of unstructured data, and realize the conversion from database system data management to content management.
(4) IBASE uses the cornerstone of object-oriented technology to closely integrate enterprise business data with business logic. It is especially suitable for expressing complex data objects and multimedia objects.
(5) IBASE is a database generated to meet the needs of Internet development. Based on the concept of a wide area network (WAN)-based massive database, iBase web is an online resource management system, the Web server and database server are directly integrated into a whole, making the database system and database technology an important and integral part of the Web, it breaks through the limitations that databases only act as the background role of the web system, and achieves an organic and seamless combination of databases and web, this has opened up a broader field for information management on the Internet/Intranet and even e-commerce applications.
(6) IBASE is fully compatible with various large and medium-sized databases and provides import and link support for traditional relational databases, such as Oracle, Sybase, sqlserver, DB2, and Informix.
After the above analysis, we can predict that with the rapid development of network technology and network application technology, non-structured databases based on internet applications will become another important and hot technology after hierarchical databases, mesh databases, and relational databases.