Learning SQL

You can correct me if I'm wrong or just tell what to add.
I'd be very grateful.

01. Data and Database

1.   Data
   
2.   Database
   
3.   Types of Databases and Database Systems
   
4.   Database Management System
   
5.   Table
   
6.   Structured Query Language
   
7.   SQL Statement
   
8.   SQL Keywords
   

02. Database and Table Statements

1.   To write first SQL statement
   
2.   Database statements
   
3.   Data Types
   
4.   Constraints
   
5.   Table statements
   

03. Data and Database

1.   SELECT/FROM
   
2.   SELECT DISTINCT
   
3.   WHERE
   
4.   ORDER BY ASC|DESC
   
5.   AND
   
6.   OR
   
7.   Combined AND and OR
   
8.   NOT
   
9.   IS NULL|IS NOT NULL
   
10.   UPDATE/SET
    
11.   DELETE FROM
    
12.   LIMIT
    
13.   AS
    

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01. Data and Database

1. Data:

• Data is a collection of facts, figures and values from different source.

2. Database (DB):

• DB is a collection of logically related data in a specific subject area that is structured in a specific way.
• If data in a database is not logically related, it can lead to several issues.

3. Types of Databases and Database Systems:

• Relational Database (RDB)

  • stores and provides access to data points that are related to one another.
  
  
  

• Object-Oriented Database (OPDB)

  • based on the principles of object-oriented programming (OOP).
    
    
  • Main components:
    • Objects - represent real-world entities
    • Classes - act as a template for creating object
    • Inheritance - an inherit attributes and methods
    • Methods - represent the behaviors or actions
    • Attributes - hold properties of an object
    • Encapsulation - binds data atributes and methods
    • Polymorphism - helps in write generic reusable code
    • Persistence - objects continuing to exit
    • Identity - objects is as assinged unique identifier
    • Transactions - provide reability with features
    

• Graph Database (GDB)
  • uses graph structures for semantic queries with nodes, edges and properties to represent and store data.
  

• Distributed Database (DDB)
  • is stored across multiple locations.
  

• Centralized Database (CDB)

  • is located, stored and maintained in a single location.
  
  
  

• Cloud Database

  • is deployed, delivered and accessed in the cloud.
  
  
  

• NoSQL Database (Not Only SQL)

  • is purpose-built for non-relational data models.
  
  
  

• Others

  • there are many different types and systems.

4. Database Management System (DBMS):

• DBMS is a software system that is used to manage databases.

• It provides a way to create, store, retrieve, update, and manage data efficiently and securely.
  
  

• Examples:

  • MySQL
  • PostgreSQL
  • Oracle Database
  • Microsoft SQL Server
  • MongoDB - a NoSQL DBMS
  • SQLite
  • Redis - for in-memory data storage
  • Cassandra - for distributed, NoSQL databases

5. Table:

• Table is a collection of data in a tabular form.
  • Tuple is a row in a table.
  • Attribute is a column in a table.

6. Structured Query Language (SQL):

• SQL lets you to access and manipulate databases.
  
  
• Examples:
  • Execute queries against a database.
  • Retrieve data from a database.
  • Insert records in a database.
  • Update records in database.
  • Delete records in database.
  • Create new databases.
  • Create new tables in a database.
  • Create stored procedures in a database.
  • Create views in a database.
  • Set a permission on tables, procedures and views.

7. SQL Statement:

• SQL statement is a set of instruction that consists of identifiers, parameters, variables, names, data types and SQL reserved words that compiles successfully.

8. SQL Keywords:

• SQL keywords are reserved words.
• They do something and can’t be used as names.