Mirjalol Tavasharov Independence work of English Theme: Database Teacher

2. History of database
The size, capabilities and performance of databases and related DBMS have increased by orders of magnitude. This increase in productivity was provided by technological progress in the field of processors, computer memory, computer storage and computer networks. The database concept was made possible by the advent of direct-access data carriers, such as magnetic disks, which became widely available in the mid-1960s; earlier systems relied on sequential data storage on magnetic tape. The subsequent development of database technology can be divided into three epochs based on a model or data structure: navigation, SQL/relational, and post-relational.
The two main early navigational data models were the hierarchical model and the CODASYL (network model) model. They were characterized by the use of pointers (often physical disk addresses) to track relationships from one record to another.The relational model, first proposed in 1970 by Edgar F. Coddom has moved away from this tradition, insisting that applications should search for data by content, not by links. The relational model uses sets of ledger-style tables, each of which is used for a different type of entity. It wasn't until the mid-1980s that computer hardware became powerful enough to allow widespread deployment of relational systems (DBMS plus applications). However, by the early 1990s, relational systems dominated all large-scale data processing applications, and as of 2018 they remain dominant: IBM Db2, Oracle, MySQL, and Microsoft SQL Server are the most popular DBMS.[9] The dominant database language, standardized SQL for the relational model, influenced database languages for other data models.[quote needed]
Object databases were developed in the 1980s to overcome the inconvenience of the object–relational impedance mismatch, which led to the introduction of the term "post-relational", as well as to the development of hybrid object–relational databases.
The next generation of post-relational databases in the late 2000s became known as NoSQL databases, introducing fast key and value stores and document-oriented databases. The competing "next generation", known as NewSQL databases, attempted new implementations that retained the relational/SQL model, aiming to match the high performance of NoSQL compared to commercially available relational databases.
1960s, navigation DBMS