DEV Community

Cover image for Unlocking the Power of Databases: A Brief Overview of SQL

Unlocking the Power of Databases: A Brief Overview of SQL

This article was co-authored by @cristieneil.

Introduction

Embark on a technological journey where you’ll appreciate how SQL orchestrates efficient data navigation.

Imagine you're about to begin your first year of app development, eager to create an application that allows users to add, remove, and change elements. The excitement of seeing buttons clicked and modifications made to the data and app states was short-lived because every time the page refreshed, it erased what the user had done, like a digital Etch-a-Sketch. Before your data can be engraved, you must first discover a way to store it. Databases play an important role here. A database is a well-organized collection of information that can be accessed or stored on a computer system¹. SQL, which is primarily utilized in relational databases, is a language that can be used to communicate with these tools.

The use of a Database Management System (DBMS) seamlessly integrates with SQL, as SQL is the language of choice for accessing and modifying stored data. Specifically, Structured Query Language (SQL) serves as a programming language tailored for the storage and manipulation of data within relational databases. In this relational database framework, data is structured into tables, where rows and columns delineate distinct data attributes and their interconnections². When a SQL command is executed, the Database Management System (DBMS) adeptly identifies the most efficient approach for its implementation. The SQL engine embedded within the DBMS interprets the specific task at hand and guides the execution process accordingly³.

What is SQL?

The Structured Query Language, commonly known as SQL (pronounced as ess-kew-el or sequel), is a standardized programming language used for relational databases to operate, access, store, retrieve, and manipulate the data in them⁴. End users can use it to interact with databases, including creating, updating, and removing them. MySQL, PostgreSQL, Microsoft SQL Server, and Oracle Databases are among the extensively utilized SQL databases, compatible with macOS, Windows, and Linux operating systems⁵.

SQL is important for data management systems because it allows for the efficient organization and manipulation of large amounts of data, and has become the standard language for relational databases since its adoption by ANSI in 1986. (ISO/IEC 9075:2016). SQL is used in various types of database systems, including proprietary and open-source RDBMSes, and has various implementations such as command-line, GUI, SQL programs and APIs⁶.

Brief History of SQL

In the early 1970s, IBM introduced SQL, a programming language that would significantly impact the realm of data management. Its formal introduction to the public occurred in 1974 when Donald Chamberlin and Raymond Boyce published the article "SEQUEL: A Structured English Query Language," unveiling SQL to the world. Initially recognized as the Structured English Query Language (SEQUEL), the term was later shortened to SQL. Subsequently, SQL gained recognition as a standard by the American National Standards Institute (ANSI) in 1986 and the International Organization for Standardization (ISO) in 1987. Over the years, SQL underwent several updates, starting with SQL-86, followed by revisions leading to SQL-89, SQL-92, SQL:1999, SQL:2003, and beyond⁷.

The History of SQL Standards
Retrieved from https://learnsql.com/blog/history-of-sql-standards

Reflecting on the rich history of SQL, its inception marked a significant milestone not only in the tech industry but also globally. The early versions focused on standardizing and stabilizing the programming language itself, while subsequent updates laid the foundation for the modern SQL we have today.

Advantages and Disadvantages
Advantages of Using SQL

I. Standardization and Compatibility
Being recognized by both the American National Standards Institute (ANSI) and the International Organization for Standardization (ISO), it is considered as a standardized language⁸. When referring to standardization, learning SQL will enable you to interact with any database that understands SQL, examples of which are MySQL, Oracle, and SQL Server. This compatibility makes SQL a flexible tool in managing data across various platforms⁹.

II. High-Level Declarative Language
When using SQL, you simply have to describe what you want to do and not how to do it which makes it a high-level declarative language. We declare what we want to achieve and are solely concerned about the output. For instance, when retrieving data from a database you need not to write complex algorithms, instead a simple SQL query will do the job.This abstraction simplifies the writing and comprehension of SQL in contrast to low-level programming languages¹⁰.

III. Comprehensive and Well-Documented
From simple data retrieval to complex data manipulation and analysis, SQL allows you to perform a wide range of tasks using its comprehensive set of commands. It also offers various functions for handling dates, strings, and mathematical calculations¹¹. Additionally, you can find abundant online resources, tutorials, and community forums regarding SQL which makes it easier for developers in learning and troubleshooting SQL more effectively thus, it is well-documented¹².

IV. Scalability and Efficiency
It can hold a vast amount of data and can be adjusted to meet the needs of the application whether scaling up or down. It means that it can adapt to changes when increasing or decreasing the number of users, transactions, or data. The retrieval and manipulation of data are also done quickly and efficiently since SQL databases have fast query processing capabilities¹³.

V. Strong Security
SQL databases incorporate built-in user authentication mechanisms in verifying the identity of users prior to granting an access to the database to ensure that only authorized users can enter, safeguarding data accessibility. It also supports encryption to protect at rest and in transit sensitive data. Through a system of permissions and roles, administrators can control access to the database and what actions they can perform. You can also utilize column-level protection which restricts access to specific columns in a table based on user roles and permissions, particularly useful for managing sensitive data like personally identifiable information (PII) and row-level protection, facilitated by Row-Level Security (RLS), that controls access to individual rows in a database table, ensuring users only see records relevant to them¹⁴.

Disadvantages of using SQL

I. Complex Interface
Few of the users are having a hard time dealing with the database due to its complex interface. Those who are new to programming may find SQL difficult and complex which can lead to errors and mistakes in database management since it requires a solid understanding of database concepts such as tables, relationships, keys, normalization, etc. SQL can be unforgiving when it comes to errors¹⁵.

II. Expensive
Programmers may not be able to access some versions of SQL since it is costly. Purchasing and maintaining certain SQL databases and other related softwares may incur significant costs¹³.

III. Partial Control and Performance Issues
Hidden business rules in SQL databases through stored procedures, triggers and constraints, can restrict user control over data operations, affecting integrity and consistency¹⁶. As databases grow, query performance may decline due to increased data scanning, especially with complex queries. Partial revokes offer fine-grained privilege restriction, while Dynamic Data Masking (DDM) secures sensitive data without altering the database content. Contained databases in SQL Server isolate databases from the hosting instance, enhancing security with internal metadata maintenance and database-level authentication¹⁷.

IV. Vulnerability to SQL Injection Attacks
SQL databases are susceptible to SQL injection attacks, a prevalent method used by hackers to tamper with or exploit SQL queries. Through SQL injection, attackers can modify SQL queries, potentially enabling them to access unauthorized data, manipulate data, or cause data loss. Preventing SQL injection attacks necessitates implementing measures like input validation and parameterized queries, which demand careful coding practices and a comprehensive grasp of SQL¹⁸.

V. Limited Support to Unstructured Data
SQL databases are primarily designed to manage structured data with well-defined data types. Although they can accommodate unstructured data like text, they aren't optimized for storing and querying unstructured data such as images, videos, and social media posts. Consequently, SQL databases may not be the most suitable option for applications dealing with substantial amounts of unstructured data. For instance, a social media platform requiring storage and retrieval of millions of user posts, images, and videos might find SQL databases less suitable¹³.

Alternatives to SQL

You are free to explore these alternatives that address the mentioned disadvantages.

  1. NoSQL databases such as MongoDB, CouchDB, and Cassandra provide a more adaptable and user-friendly interface, eliminating the need for a rigid schema and allowing for natural data representation, which is particularly advantageous for complex data structures¹⁹.

  2. Open-source databases like PostgreSQL and MySQL offer a cost-effective alternative to commercial SQL databases, providing many similar features while being free to use and supported by large, active communities²⁰.

  3. NewSQL databases like CockroachDB and VoltDB deliver full ACID compliance alongside horizontal scalability, granting developers extensive control over their data without compromising scalability²¹.

  4. For certain workloads, in-memory databases like Redis and Memcached can deliver superior performance by storing data in memory rather than on disk, facilitating faster data access²² ²³.

  5. To mitigate SQL injection risks, Object-Relational Mapping (ORM) tools like Hibernate for Java, SQLAlchemy for Python, or Entity Framework for .NET can automatically generate SQL queries and handle input sanitization effectively²⁴ ²⁵.

  6. Document-oriented NoSQL databases like MongoDB and CouchDB are engineered for storing, retrieving, and managing semi-structured data, offering a more flexible schema compared to SQL databases, making them suitable for unstructured and semi-structured data storage²⁶.

Conclusion

The symbiotic relationship between Database Management Systems (DBMS) and Structured Query Language (SQL) is the foundation of effective data organization, allowing for seamless information storage, retrieval, and manipulation. SQL, with its rich history, offers standardization, a high-level declarative language, comprehensiveness, scalability, and robust security measures. Despite its complexities and potential costs, SQL's widespread adoption underscores its significance in diverse industries. In the dynamic realm of data management, a profound grasp of SQL and its alternatives empowers professionals to make informed decisions, ensuring optimal efficiency, security, and adaptability. As technological advances continue, choosing between SQL and other alternatives becomes a strategic endeavor, requiring a thorough evaluation of their different benefits and downsides in order to meet the unique requirements of modern data-driven applications.

References:

  1. Saxena, Tanya. 2019. “What Is Database?” GeeksforGeeks. September 12, 2019. https://www.geeksforgeeks.org/what-is-database/.
  2. Amazon AWS. 2023. “What Is SQL? - SQL - AWS.” Amazon Web Services, Inc. 2023. https://aws.amazon.com/what-is/sql/.
  3. Daga, Bikash. 2022. “Database Management Systems and SQL – Tutorial for Beginners.” FreeCodeCamp.org. October 12, 2022. https://www.freecodecamp.org/news/dbms-and-sql-basics/.
  4. w3schools. 2019. “SQL Introduction.” W3schools.com. 2019. https://www.w3schools.com/sql/sql_intro.asp.
  5. SolarWinds. n.d. “What Is SQL Database? - IT Glossary | SolarWinds.” Www.solarwinds.com. https://www.solarwinds.com/resources/it-glossary/sql-database.
  6. Loshin, Peter. 2022. “What Is Structured Query Language (SQL)?” TechTarget. February 2022. https://www.techtarget.com/searchdatamanagement/definition/SQL.
  7. Kozubek-Krycuń, Agnieszka . 2020. “The History of SQL Standards.” LearnSQL.com. December 8, 2020. https://learnsql.com/blog/history-of-sql-standards/.
  8. Kelechava, Brad. 2018. “The SQL Standard - ISO/IEC 9075:2023 (ANSI X3.135) - ANSI Blog.” The ANSI Blog. October 5, 2018. https://blog.ansi.org/sql-standard-iso-iec-9075-2023-ansi-x3-135.
  9. “SQL Language Reference.” n.d. Oracle Help Center. Accessed February 19, 2024. https://docs.oracle.com/en/database/oracle/oracle-database/21/sqlrf/index.html.
  10. “SQL Academy - Learn SQL Online.” n.d. Sql.ac. https://sql.ac/blog/what-language-level-is-sql-understanding-the-scope-and-elements-of-sql.
  11. “SQL Date Functions: A Comprehensive List of Date Functions in SQL.” n.d. SQL Tutorial. Accessed February 19, 2024. https://www.sqltutorial.org/sql-date-functions.
  12. “SQL Server Functions.” n.d. Www.w3schools.com. https://www.w3schools.com/sql/sql_ref_sqlserver.asp.
  13. “Advantages and Disadvantages of SQL - GeeksforGeeks.” 2020. GeeksforGeeks. April 9, 2020. https://www.geeksforgeeks.org/advantages-and-disadvantages-of-sql.
  14. dplessMSFT. 2023. “SQL Server Security Best Practices - SQL Server.” Learn.microsoft.com. April 3, 2023. https://learn.microsoft.com/en-us/sql/relational-databases/security/sql-server-security-best-practices?view=sql-server-ver16.
  15. Drkusic, Emil. 2020. “Learn SQL: How to Write a Complex SELECT Query.” SQL Shack - Articles about Database Auditing, Server Performance, Data Recovery, and More. February 4, 2020. https://www.sqlshack.com/learn-sql-how-to-write-a-complex-select-query.
  16. WilliamDAssafMSFT. 2023. “Contained Databases - SQL Server.” Learn.microsoft.com. February 28, 2023. https://learn.microsoft.com/en-us/sql/relational-databases/databases/contained-databases?view=sql-server-ver16..
  17. VanMSFT. 2023. “Dynamic Data Masking - SQL Server.” Learn.microsoft.com. October 31, 2023. https://learn.microsoft.com/en-us/sql/relational-databases/security/dynamic-data-masking?view=sql-server-ver16..
  18. “Advantages and Disadvantages of SQL.” n.d. AspiringYouths. https://aspiringyouths.com/advantages-disadvantages/sql/.
  19. “What Are Good Alternatives to SQL (the Language)?” n.d. Stack Overflow. https://stackoverflow.com/questions/2497227/what-are-good-alternatives-to-sql-the-language.
  20. Kovačević, Aleksandar. 2021. “8 Best Open-Source Databases {Pros & Cons} | PhoenixNAP KB.” Knowledge Base by PhoenixNAP. April 29, 2021. https://phoenixnap.com/kb/open-source-database.
  21. Agrawal, Deepesh. 2023. “Powerful Alternatives to SQL That Will Revolutionize Database Management.” Medium. July 8, 2023. https://medium.com/@deepeshagrawal9/powerful-alternatives-to-sql-that-will-revolutionize-database-management-6da0a9f550f0.
  22. Ashraf, Haroon. 2019. “Replacing SQL Cursors with Alternatives to Avoid Performance Issues.” {Coding}Sight. March 22, 2019. https://codingsight.com/replacing-sql-cursors-with-alternatives-to-avoid-performance-issues/.
  23. “LIKE Work-around in SQL (Performance Issues).” n.d. Stack Overflow. Accessed February 19, 2024. https://stackoverflow.com/questions/3691149/like-work-around-in-sql-performance-issues.
  24. DZone. 2018. “SQL Injection Vulnerabilities and How to Prevent Them - DZone Security.” Dzone.com. January 29, 2018. https://dzone.com/articles/what-is-the-sql-injection-vulnerability-amp-how-to.
  25. Wagenseil, Paul. 2023. “How to Fix Recent SQL Injection Vulnerabilities and Avoid Future Attacks.” SC Media. February 10, 2023. https://www.scmagazine.com/resource/how-to-fix-recent-sql-injection-vulnerabilities-and-avoid-future-attacks.
  26. “Sql - Why Are Relational Databases Unsuitable for Unstructured Data?” n.d. Stack Overflow. https://stackoverflow.com/questions/21077898/why-are-relational-databases-unsuitable-for-unstructured-data.

Top comments (0)