SQL Tutorial

• What is SQL
• What is RDBMS
• Commonly Used Relational Databases
• SQL Syntax
• SQL Data Types
• SQL CREATE DATABASE
• SQL DROP DATABASE
• SQL USE
• SQL CREATE TABLE
• SQL DROP TABLE
• SQL RENAME TABLE
• SQL INSERT INTO
• SQL SELECT
• SQL WHERE
• SQL AND and OR
• SQL UPDATE
• SQL DELETE
• SQL LIKE
• SQL TOP
• SQL ORDER BY
• SQL GROUP BY
• SQL DISTINCT
• SQL Constraints
• SQL NULL
• SQL NOT NULL
• SQL DEFAULT
• SQL UNIQUE
• SQL Primary Key
• SQL Foreign Key
• SQL CHECK
• SQL INDEX
• SQL JOIN
• SQL INNER JOIN
• SQL LEFT JOIN
• SQL RIGHT JOIN
• SQL FULL JOIN
• SQL SELF JOIN
• SQL CROSS JOIN
• SQL UNION and UNION ALL
• SQL AS
• SQL ALTER TABLE
• SQL TRUNCATE TABLE
• SQL View
• SQL HAVING
• SQL Transaction
• SQL Temporary Tables
• SQL Clone Table
• SQL Sub Query
• SQL AUTO_INCREMENT
• SQL Injection

What is RDBMS

RDBMS stands for Relational Database Management System. It is a type of database management system (DBMS) that stores data in a structured format, using rows and columns. This structure allows users to access data in relation to other pieces of data in the database.

Here are some key aspects of RDBMS:

1. Data stored in tables: Data in an RDBMS is stored in database objects which are called tables. A table is a collection of related data entries and it consists of columns and rows. Each column represents an attribute (or field) and each row represents a record.

2. Relational model: The relational model means that the logical data structures��the data tables, views, and indexes��are separate from the physical storage structures. This separation means that database administrators can manage physical data storage without affecting access to that data as a logical structure.

3. Data Consistency with ACID properties: ACID stands for Atomicity, Consistency, Isolation, Durability. These are a set of properties that guarantee that database transactions are processed reliably.

4. Support for SQL: RDBMS typically come with support for the SQL (Structured Query Language), which is a standardized language for querying and manipulating the data in databases.

5. Data Integrity: In RDBMS, data is not required to be repeated everywhere. The architecture is built around integrity rules to help improve accuracy and consistency, and these rules can be customized to meet the particular needs of the database.

6. Normalization: RDBMS supports normalization, a process that organizes tables in a manner that reduces redundancy and dependency of data. It divides larger tables to smaller tables and links them using relationships.

Some examples of popular RDBMSs include Oracle Database, Microsoft SQL Server, MySQL, and PostgreSQL. These systems are used in a variety of contexts, ranging from small applications that run on personal computers to large systems that run on mainframes.