May 1, 2024
4 minute read
Query language is a formal language used to query and retrieve data from a database. It allows users to interact with the database and perform operations such as data retrieval, insertion, deletion, and modification. Query languages are designed to be easy to use and understand, making them accessible to users with a wide range of technical backgrounds.
History and Evolution of Query Languages
The first query language was developed in the early 1970s by Edgar F. Codd, who is considered the father of the relational database model. Codd's query language, known as SEQUEL (Structured English Query Language), served as the foundation for the development of SQL (Structured Query Language), which is the most widely used query language today.
Over the years, query languages have evolved significantly, with the introduction of new features and enhancements. The development of graphical user interfaces (GUIs) has made query languages more accessible to users who are not familiar with programming. Additionally, the emergence of NoSQL databases has led to the development of new query languages that are designed specifically for these types of databases.
Types of Query Languages
There are two main types of query languages: declarative and procedural.
-
Declarative query languages specify what data to retrieve from the database, but they do not specify how to retrieve it. The database management system (DBMS) is responsible for determining the most efficient way to retrieve the data.
-
Procedural query languages specify both what data to retrieve from the database and how to retrieve it. Procedural query languages are less common than declarative query languages, but they can be useful in certain situations, such as when the user needs to have more control over the execution of the query.
Benefits of Learning a Query Language
cbh5t8|
Find a path to becoming a Query language. Learn more at:
OpenCourser.com/topic/cbh5t8/query
Reading list
We've selected 11 books
that we think will supplement your
learning. Use these to
develop background knowledge, enrich your coursework, and gain a
deeper understanding of the topics covered in
Query language.
Is the fifth edition of a popular book on writing SQL queries. It is intended for an audience that is new to a database.
Collection of recipes for solving common problems with Transact-SQL. It covers a wide range of topics, from basic queries to complex data manipulation tasks.
Is an in-depth tutorial on database design and implementation topics using SQL Server, although many of the concepts also apply to other databases. The readers are assumed to have some familiarity with SQL.
Covers a wide range of SQL Server 2012 topics, including query languages, database design, and advanced topics such as data mining and reporting services.
Good, all-around primer for people who want to get up to speed with SQL. It also introduces topics such as indexing, normalization, and backup/recovery.
Focuses on performance tuning for MySQL databases. It covers topics such as indexing, caching, and query optimization.
Provides a deep dive into the performance characteristics of SQL queries. It covers topics such as query plans, indexes, and performance tuning.
Is an introduction to SQL using the Oracle database. It covers a wide range of topics, from basic queries to advanced features such as stored procedures and triggers.
Focuses on how to query XML data from a variety of sources, such as files and databases. It also explores advanced topics such as XSLT and XPath, as well as emerging XML query standards.
Is intended to teach the basics of SQL and covers topics such as data types, queries, joins, and subqueries.
Collects common mistakes that database programmers make when writing SQL queries. A large focus is on performance issues.
For more information about how these books relate to this course, visit:
OpenCourser.com/topic/cbh5t8/query
Save
