SQL Tutorial
- Introduction to SQL
- SQL Syntax
- SQL Data Types
- SQL Operators
SQL Database
- SQL CREATE Database
- SQL DROP Database
- SQL RENAME Database
- SQL SELECT Database
SQL Table
- What is Table
- SQL CREATE TABLE
- SQL DROP TABLE
- SQL DELETE TABLE
- SQL RENAME TABLE
- SQL TRUNCATE TABLE
- SQL COPY TABLE
- SQL TEMP TABLE
- SQL ALTER TABLE
SQL Select
- SELECT Statement
- SQL SELECT UNIQUE
- SQL SELECT DISTINCT
- SQL SELECT COUNT
- SQL SELECT TOP
- SQL SELECT FIRST
- SQL SELECT LAST
- SQL SELECT RANDOM
- SQL SELECT IN
- SQL SELECT Multiple
- SQL SELECT DATE
- SQL SELECT SUM
- SQL SELECT NULL
SQL Clause
- SQL WHERE
- SQL AND
- SQL OR
- SQL WITH
- SQL AS
- SQL HAVING Clause
SQL Order By
- ORDER BY Clause
- ORDER BY ASC
- ORDER BY DESC
- ORDER BY RANDOM
- ORDER BY LIMIT
- ORDER BY Multiple Cols
SQL Insert
- INSERT Statement
- INSERT Multiple Rows
SQL Update
- UPDATE Statement
- SQL UPDATE JOIN
- SQL UPDATE DATE
SQL Delete
- DELETE Statement
- SQL DELETE TABLE
- SQL DELETE ROW
- SQL DELETE All Rows
- DELETE Duplicate Rows
- SQL DELETE DATABASE
- SQL DELETE VIEW
- SQL DELETE JOIN
SQL Join
- SQL JOIN
- SQL Outer Join
- SQL Left Join
- SQL Right Join
- SQL Full Join
- SQL Cross Join
SQL Keys
- Primary Key
- Foreign Key
- Composite Key
- Unique Key
- Alternate Key
Difference
- SQL vs NoSQL
- IN vs EXISTS
- Group By vs Order By
- WHERE vs HAVING
- Where condition in SQL
SQL Injection
- SQL Injection
SQL String Functions
- SQL String Functions
- LTRIM Function in SQL
- UPPER Function in SQL
- RTRIM Function in SQL
SQL Tutorial
The SQL tutorial provides both basic and advanced concepts of SQL. Our tutorial is designed to cater to both beginners and professionals alike.
Introduction to SQL
SQL, or Structured Query Language, is a programming language used to communicate with and manipulate databases. It allows users to interact with databases by performing tasks such as querying data, inserting new records, updating existing records, and deleting records. SQL is a powerful tool for managing and analyzing large sets of data, making it essential for anyone working with databases. It is a standard language for relational database management systems (RDBMS) like MySQL, PostgreSQL, Oracle, and SQL Server.
What is SQL?
SQL stands for Structured Query Language, and it is a programming language used for managing and manipulating relational databases. It allows users to query, insert, update, and delete data from databases, as well as create, modify, and delete tables and views. SQL is widely used in a variety of applications, from small personal databases to large enterprise systems.
Why use SQL?
SQL (Structured Query Language) is used for a variety of reasons across different industries due to its versatility and efficiency in managing and analyzing large data sets. Here are the key reasons why SQL is widely used:
- Data Management and Analysis: SQL is a standard language for storing, retrieving, and manipulating data in relational databases. It allows users to perform tasks such as creating, updating, and deleting databases, making it indispensable for managing and analyzing large data sets efficiently.
- Widespread Use Across Industries: SQL is used in almost every mid to large-sized organization, including sectors like marketing, finance, healthcare, and technology. Its applications span across data and business analytics, development, and data science, making it a crucial tool for professionals in these fields.
- Versatility and Accessibility: SQL is not just for technical professionals; its utility extends to both technical and non-technical roles. It enables professionals to unlock the potential of data, leading to informed decisions and innovative solutions. This versatility makes SQL a valuable skill for anyone navigating the digital landscape, future-proofing their career in an increasingly data-driven world.
- Real-time Data Processing: SQL databases can be connected to live, real-time dashboards that visualize data, making it possible to analyze and act on data in real-time. This capability is particularly useful in healthcare, where SQL can be used to manipulate and analyze patient information stored in clinical databases, build dashboards on user health data, and generate patient reports.
- Efficiency and Scalability: SQL enables users to work with volumes of data that would be impractical or impossible to handle with other tools. It allows for the processing of millions of transactions, storing terabytes of data, and getting results in seconds. This efficiency and scalability make SQL a preferred choice for organizations that need to manage large data sets effectivel.
- Declarative Nature: Unlike many programming languages that require detailed instructions to perform a task, SQL is declarative. Users specify what data they want, and the SQL engine takes care of the rest. This makes SQL relatively easy to learn, especially for beginners, and allows users to focus on the data they need without getting bogged down in the complexities of data retrieval.
- Bridge to Data: SQL serves as a bridge that connects various professionals to the world of data. It provides the means to access and analyze data without always relying on IT experts, making it a valuable skill for data analysts, marketers, business owners, and more. As the digital landscape continues to evolve and the demand for data-driven insights grows, SQL’s importance is undeniable.
History of SQL
The history of SQL can be traced back to the early 1970s at IBM. Here’s a breakdown of the key milestones:
- 1970: Edgar F. Codd publishes his influential paper, “A Relational Model of Data for Large Shared Data Banks,” which laid the foundation for relational databases.
- Early 1970s: Donald D. Chamberlin and Raymond F. Boyce at IBM develop SEQUEL (Structured English Query Language) to interact with IBM’s System R, a relational database management system.
- 1979: Relational Software, Inc. (later known as Oracle) releases the first commercially available implementation of SQL.
- 1986: The American National Standards Institute (ANSI) standardizes SQL as SQL-86.
- 1987: The International Organization for Standardization (ISO) adopts SQL as a standard.
- Since then: SQL has undergone several revisions (e.g., SQL-92, SQL:1999) to incorporate new features and keep pace with evolving database needs.