What is SQL in DBMS – Definition, Basics of SQL, & Uses

A programming language used to manage and manipulate databases is known as SQL or Structured Query Language. It offers features for creating and modifying tables, and updating and deleting data, based on specific criteria. Now, let’s understand what is SQL, and the brief origins of SQL.

SQL was developed by Donald Chamberlin and Raymond Boyce at IBM in the 1970s. SQL was originally known as SEQUEL and was standardized by the American National Standards Institute (ANSI) in 1986.

The first version was launched in 1989 after IBM developed the prototype of a relational database in 1986. SQL was initially developed to manage the stored data in IBM’s relational database management system also known as RDBMS. The first relational database systems were released with the support of SQL and it included Microsoft SQL Server, IBM D2, and Oracle. 

SQL became an essential tool for working with these databases and evolved with new capabilities over the years. In 2003, SQL was introduced with features like window functions and XML. In 2006, SQL started supporting XML Query Language and in 2011 it improved the support for temporal databases.

The SQL definition for what is SQL in DBMS remains the same as it is used to manage data that is stored in relational database management systems. In this blog, we will learn about SQL basics, SQL definition, SQL meaning, what is it used for, its process, and standards.

Basics of SQL

SQL allows users to manipulate and access data that is stored in a database and is widely used for web development. The following are a few SQL basics that every user must know about:

• SQL manages and manipulates relational databases.
• It operates on tables consisting of rows and columns.
• It also provides a standard way of accessing and manipulating data in a database.
• It is also used to create and modify the database schema, including tables, columns, and relationships between tables.
• SQL allows the user to insert, update, and delete data in a database.
• It retrieves data from one or more tables using queries.
• It uses keywords like SELECT, FROM, WHERE, and JOIN to construct queries.
• Statements of SQL are executed by a database management system like MySQL, PostgreSQL, or Microsoft SQL Server.
• It is widely used in various industries like finance, healthcare, and e-commerce.
• It is an essential tool for managing and processing large amounts of data.

SQL Statement and Its Types

Let us understand what is SQL statement. The commands that are used to manage and manipulate relational databases are known as SQL statements. Some common types of SQL commands are:

• Data Definition Language (DDL): DDL commands in SQL are used to create, delete, and modify database objects like tables, indexes, and views.
• Data Manipulation Language (DML): DML commands in SQL are used to manipulate the stored data in tables. 
• Data Control Language (DCL): These SQL commands are used to manage access to database objects.
• Data Query Language (DQL): These commands are used to retrieve data from one or more tables. 
• Transaction Control Language (TCL): These SQL commands are used to manage transactions, which include sets of database operations that are executed as a single unit. 

Also, know how normal forms in SQL work to remove data redundancy and improving data reliability

What is SQL Used For?

Now that we have covered the history of SQL along with its basics and statements, let us find out what is SQL used for. Following are a few examples:

• To Create Database: SQL is used to create databases and define the structure of the tables within them, it includes the data types of the columns, the constraints that ensure data integrity, and the relationships between tables.
• To Insert and Update Data: SQL is used to insert data into tables, delete records that are no longer needed, and update existing records.
• To Query Data: SQL is used to retrieve data from more than one table using queries. These can be both, simple or complex. They involve filtering, sorting, and aggregating data to answer specific questions.
• To Analyze Data: SQL is used to perform complex analysis of data, which includes data mining and statistical analysis, to identify patterns in the data.
• To Build Applications: SQL is also useful in building applications that interact with databases, like mobile apps, web applications, and desktop applications.
• To Manage Databases: SQL is used to manage databases, it includes optimizing database performance, backing up and restoring data, and administering user accounts and permissions.

SQL Process

To know what is SQL process is, you must go through the steps to get an overview of the SQL process. The SQL process involves planning and designing the database schema. Then the query is used in the database for SQL commands and optimizing queries. Later, testing queries to ensure they work correctly, and maintaining the database to keep it running smoothly. To get a detailed understanding of the subject one can pursue an SQL course. Follow the steps below to explain the SQL process: 

• Step 1 – Planning: The foremost step in this process is to plan what the user wants to do. Planning includes determining which tables to use, which columns to modify, and which conditions to apply to filter the data.

• Step 2- Designing: The step after planning is to design the database schema. It includes defining the tables, columns, and relationships between them. It helps create the tables, set the data types, and create foreign keys to establish relationships between the tables.

• Step 3- Querying: After the database schema is designed, the user can start querying the database to retrieve, insert, update, or delete data. This involves using various SQL commands.

• Step 4- Optimizing: As the user writes SQL queries, it becomes important to optimize them for performance. It involves using indexes, using efficient query syntax, and minimizing the number of joins and subqueries.

• Step 5- Testing: Once the SQL queries are written and optimized for performance, the user should test them. It involves running the queries on a test database to ensure that the results are correct.

• Step 6- Maintaining: After the SQL process is running, the user will need to maintain the database to keep it running smoothly. It involves tasks like monitoring, backup, and applying upgrades to the database software.

List of SQL Commands

Below are the most commonly used commands in SQL: 

• SELECT: This command retrieves the data from a database.
• INSERT: This command is used to add new data to the database.
• UPDATE: This command modifies the existing data in the database.
• DELETE: This removes the data from the database.
• CREATE: This command creates a new database, table, or other database objects.
• DROP: This command is used to delete a database, table, or other database objects.
• ALTER: This command modifies the structure of a database table.
• JOIN: This command combines data from multiple tables.
• GROUP BY: This command is used to group data based on specified columns.
• LIMIT: This command limits the number of rows returned by a query.

What are SQL Standards?

A set of specifications that ensure consistency and interoperability among different SQL database management systems is referred to as SQL Standards. The following examples highlight more what are SQL standards:

SQL-86	The First SQL standard was developed by the American National Standards Institute (ANSI) in 1986
SQL-89	It is also known as SQL1. It introduced many important features, like the SELECT, FROM, and WHERE clauses.
SQL-92	It is also known as SQL2. It added support for more advanced features such as subqueries and views.
SQL: 1999	It added support for object-relational features and XML data.
SQL: 2003	This added support for window functions, recursive queries, and more advanced features.
SQL: 2008	It improved support for XML data, and added support for spatial data, and other features.
SQL: 2011	It added support for temporal data and other features.

SQL Language Elements

To understand what is SQL language elements are, it is important to know how many elements it consists of and what they are used for. Check the key elements of SQL below: 

• Keywords: A variety of keywords are used to define the structure and perform operations on the database. Its examples include SELECT, INSERT, UPDATE, DELETE, CREATE, ALTER, and DROP.
• Identifiers: These are the names of objects in the database, like user IDs, tables, and columns.
• Constraints: These are the rules that are applied to the data in a database to maintain its integrity and consistency. Various types of constraints include PRIMARY KEY, FOREIGN KEY, UNIQUE, and CHECK.
• Functions: There are a variety of built-in SQL functions that can be used to manipulate data within a database. Its examples include COUNT, SUM, AVG, MAX, MIN, and CONCAT.
• Search Conditions: The conditions used to select a subset of the rows from a table or used to control statements like an IF statement to determine control of flow.
• Indexes: The performance of database queries is improved by indexes. It creates a separate data structure that allows for faster access to data. It can be created on one or more columns of a table.
• Comments: Another SQL element used to attach explanatory text to SQL statements. Though the database server does not execute any comment.
• Views: The virtual tables that are created by combining data from one or more tables are known as Views. It can be used to simplify complex queries. 

Conclusion

A powerful programming language that is widely used for managing and querying relational databases. We hope that now you understand what is SQL. It is essential for anyone working with large amounts of data, as it provides a standardized way to manage data across multiple platforms.