The first step in the journey of Java Full Stack by deep diving into SQL :

Data :

Data are the raw facts that describe the attributes/properties of an entity/object.

Database :

1. A database is a place or medium in which data stored in a systematic and organized manner.

2. On the Database, we can perform several operations such as:

   i). Create/Insert

   ii). Retrieve/Read

   iii). Update/Modify

   iv). Delete/Drop

3. All these operations are universally known as CRUD operations.

Data Base Management System(DBMS) :

1. DBMS is soft. that is used to maintain and manage the database.

2. DBMS provides us with two important features :

   i). Security

   ii). Authorization

3. To communicate with DBMS we require Query Language.

4. In DBMS we store the data in the form of files.

Classification of DBMS :

1. NDBMS: Networking Database Management System

2. HDBMS: Hierarchial Database Management System

3. OODBMS: Object-Oriented Database Management System

4. RDBMS: Relational Database Management System

   ( Stable, Flexible, Scalable, Highly demanding)

Relational Model :

1. The relational Model was introduced by a computer scientist named E.F.Codd ( Edger Frank Codd).

2. The relational model stores the data in the form of tables.

RDBMS :

1. RDBMS is a type of DBMS software that is used to maintain and manage the database.

2. RDBMS provides two important features:

   i). Security

   ii). Authorization

3. To communicate with RDBMS we require Structured Query Language(SQL).

4. In RDBMS we store the data in table form.

Interview Question :

What is the difference between DBMS and RDBMS?

Rules of E.F.Codd :

Rule 1. The data entered into the cell must be single-valued (atomic value).

why? : To prevent data loss due to transactions such as insert, update, and delete.

Rule 2. According to E.F.Codd, we can store the data in multiple tables if needed we can establish a relationship between the tables by using KEY ATTRIBUTES.

Rule 3. In RDBMS we store everything in the form of a table including #metadata.

Meta Data :

The details about the data are known as metadata.

Meta Tables :

The table store in which metadata is stored is known as metatables.

Rule 4. The data entered into the table can be validated in two steps :

i). By assigning Data Types ( #Mandatory).

ii). By assigning Constraints ( #Optional).

"As we wrap up, I want to express my gratitude for your attention. I hope this post has illuminated key takeaways about SQL. Thank you for being a part of this journey. Until next time, keep exploring and innovating!"