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It is believed that many inexperienced people do not know what the basic data structure in relational database refers to. Therefore, this paper summarizes the causes and solutions of the problem. Through this article, I hope you can solve this problem.

In a relational database, the basic data structure is a "two-dimensional table", and the relationship between tables is reflected by common fields in different tables. Relational database refers to a database that uses a relational model to organize data, while a relational model can be simply understood as a two-dimensional table model, that is, a relational database is a data organization composed of two-dimensional tables and their relationships.

The operating environment of this tutorial: windows7 system, Dell G3 computer.

Relational database refers to a database that uses a relational model to organize data, which stores data in the form of rows and columns for users to understand. A series of rows and columns in a relational database are called tables, and a group of tables make up the database. The user retrieves the data in the database through a query, which is an execution code that defines certain areas of the database. The relational model can be simply understood as a two-dimensional table model, and a relational database is a data organization composed of two-dimensional tables and their relationships.

In relational database, the basic data structure is two-dimensional table, and the relationship between tables is reflected by common fields in different tables. Each relational model is not isolated, they are not a pile of two-dimensional tables stacked together at random. In order to correctly reflect things and the relationship between things, it is necessary to carefully design the relational database.

Features:

1. Storage mode: the traditional relational database uses the table storage mode, and the data is stored in rows and columns, so it is very convenient to read and query.

two。 Storage structure: relational database stores data according to a structured method. Each data table must define each field (that is, define the structure of the table first), and then store the data according to the structure of the table. The advantage of this is that because the form and content of the data have been defined before the data is stored, the reliability and stability of the whole data table are relatively high. But the problem is that once the data is stored, it will be very difficult to modify the structure of the data table.

3. Storage specification: in order to avoid repetition, standardize the data and make full use of the storage space, the relational database stores the data in the form of the minimum relational table, so that the data management can become very clear and clear at a glance. Of course, this is mainly the case of a data table. If it is multiple tables, the situation is different, because the data involves multiple data tables, there is a complex relationship between data tables, with the increase in the number of data tables, data management will become more and more complex.

4. Expansion method: because the relational database stores the data in the data table, the bottleneck of data operation appears in the operation of multiple data tables, and the more data tables, the more serious the problem. If you want to alleviate this problem, you can only improve the processing capacity, that is, to choose a faster and higher performance computer, although this method can expand the space to a certain extent, but the expansion space must be very limited. That is, relational databases only have the ability to scale up.

5. Query method: relational database uses structured query language (SQL) to query the database. SQL has long been supported by various database manufacturers and has become the standard of the database industry. It can support database CRUD (add, query, update, delete) operations, with very powerful functions. SQL can use similar index methods to speed up query operations.

6. Normalization: in the process of database design and development, developers are usually faced with the need to operate on one or more data entities (including arrays, lists, and nested data) at the same time, so that in a relational database, a data entity is generally divided into multiple parts, and then the segmented parts are normalized, and then stored in multiple relational data tables. This is a complicated process. The good news is that with the development of software technology, quite a number of software development platforms provide some simple solutions, for example, the ORM layer (that is, object-relational mapping) can be used to map the object model in the database to the relational database based on SQL and to transform the data between different types of systems.

7. Transactionality: relational database emphasizes ACID rules (Atomicity, Consistency, Isolation, Durability), which can not only meet the requirements of transactional or complex data query, but also fully meet the requirements of high performance and operational stability of database operations. And the relational database emphasizes the strong consistency of data, and has a good support for the operation of transactions. Relational databases can control the atomicity and fine granularity of transactions and roll back transactions as soon as the operation is wrong or necessary.

8. Read and write performance: relational databases put great emphasis on data consistency and pay a huge price for reducing read and write performance, although relational databases have good reliability in storing and processing data. however, once faced with massive data processing, the efficiency will become very poor, especially in the case of high concurrent read and write, the performance will decline very badly.

9. Authorization: Oracle,SQLServer,DB2,Mysql is common in relational databases. In addition to Mysql, most relational databases need to pay a high price if they want to use them. Even the free Mysql performance is subject to many restrictions.

After reading the above, have you mastered what the basic data structure in relational database refers to? If you want to learn more skills or want to know more about it, you are welcome to follow the industry information channel, thank you for reading!

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