SQL Essentials
SQL Essentials
all you need to know as a junior dev
About the Book
RDBMS, or Relational Database Management Systems are the most popular systems today in managing large databases. Most of the data management applications are backed up by an RDBMS like MySQL, or Postgres, or Oracle, or SQL Server or other. For that reason, it is very important to learn SQL, Structured Query Language, the language that is used to retrieve and manipulate data that are stored inside a relational database. MySQL is going to be the RDBMS that we will install and use for learning. MySQL is very popular in many production systems. So, learning to work with MySQL will give you a very good asset as a Web developer.
Table of Contents
- Credits To Photo on Cover Page
-
About and Copyright Notice
-
1 - Introduction to RDBMS
- Summary
- Learning Goals
- Introduction
- RDBMS Server
- Client - Server Model
- SQL
- Data Modeling
- Like sheets on EXCEL or Google spreadsheets
- Tables and Business Entities
- Database Design
- MySQL
- Tasks and Quizzes
-
2 - Manage MySQL Server
- Summary
- Learning Goals
- Introduction
- MySQL Installation
- Verifying MySQL Running as Server
- Starting and Stopping MySQL server
- Communicating With MySQL Server
- MySQL Settings
- Closing Notes
- Tasks and Quizzes
-
3 - Basic SQL Commands
- Summary
- Learning Goals
- Introduction
- Create the database
- Select Database To Work With
- Creating Tables
- Inserting Data Into a Table
- Selecting Rows from Table
- Limiting the Rows Returned Using Criteria - where Clause
- Counting number of Entries
- Deleting Rows from Tables
- Updating Rows on a Table
-
like
operator - Closing Note
- Tasks and Quizzes
-
4 - Adding Columns And Indexes
- Summary
- Learning Goals
- Introduction
- Adding a New Column
- Indexes
- Creating an Index
- Removing an index
- Unique Indexes
- Closing Note
- Tasks and Quizzes
-
5 - Counting And Sorting Records - Limiting Results
- Summary
- Learning Goals
- Introduction
- Creating Table products
- Unique Name
- Inserting a Product
- Counting
- Sorting - Ordering Results
- Limiting Number Of Records Returned
-
Combining
where
,order by
andlimit
- Closing Note
- Tasks and Quizzes
-
6 - Foreign Keys
- Summary
- Learning Goals
- Introduction
- Model Details
- Implementation
-
Create
orders
table - Inserting Orders
- Inserting Wrong Data
- Unique order number
- Inserting Wrong Customer Id
- Try to Insert Bad Data Again
-
Creating
order_items
table -
Referential Integrity between
orders
andorder_items
-
Referential Integrity between
products
andorder_items
- Inserting Data Into The Details
- Unique Index On Multiple Columns
- Closing Note
- Valentina Studio
- Tasks and Quizzes
-
7 - Joins, Left Joins And Subqueries
- Summary
- Learning Goals
- Introduction
- Review Database Schema
- Retrieving Data
- Deleting Existing Data
- Inserting Necessary Data
-
Selecting All the Information -
join
orinner join
- More Complex Queries
- Closing Note
- Tasks and Quizzes
-
1 - Introduction to RDBMS
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