Gain insights into SQL and database fundamentals. Delve into data manipulation, administration, and normalization with practical tasks using SQL functions for backup, recovery, and user management.

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SQL is a must-know language for all types of roles, including development and data science. This course includes hands-on experience with the fundamentals of the SQL Server database including database administration.

The course covers the fundamentals of relational databases and database normalization. It offers a practical learning experience of retrieval, definition, manipulation, presentation and transformation of data through SQL functions. You will also learn database administration for backup, recovery and restore followed by managing the users, roles and privileges.

This course will teach you how to perform tasks related to SQL Server databases with hands-on experience. It covers the complete range of day-to-day operations.

A Practical Guide to SQL  and Database Fundamentals

Prod.Products Table

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## The `DISTINCT` function
The `DISTINCT` function allows us to obtain all unique values from a group of values. This function is beneficial when there are duplicates in a column in particular.

> **Note:** We can only use the `DISTINCT` function on one column, but we can still select non-unique values from other columns after using the `DISTINCT` function.

For example, the `Prod.Products` table contains various product colors, and some colors appear more than once on the table. However, we’d like to gather a unique list of colors in that table. We can do that using the following syntax:






We want to know which specific colors are available in the `Prod.Products` table. This will output three colors as our “Prod.Products” table contains four rows with two distinct colors:

Output of DINSTINCT



## Aliases
**Aliases** are temporary names used for tables and columns for queries within the database. They can be used to make certain columns or tables look easier to understand for the user or to keep the true identity of the column or table names a secret. It’s also beneficial to use aliases when writing complex queries, as it can simplify table and column names—thereforemaking the query-writing process quicker.

We can also create string aliases and non-string aliases from column or table names. It’s best practice to use the `AS` keyword after the column or table name to specify the alias because it makes the code easier to read. There are intended and accidental aliases; **intended** aliases are the ones we set using the `AS` keyword, and **accidental** aliases are written after the column name without the `AS` keyword. We can see this in the syntax below:




     

# The `DISTINCT` function
The `DISTINCT` function allows us to obtain all unique values from a group of values. This function is beneficial when there are duplicates in a column in particular.

> **Note:** We can only use the `DISTINCT` function on one column, but we can still select non-unique values from other columns after using the `DISTINCT` function.

For example, the `Prod.Products` table contains various product colors, and some colors appear more than once on the table. However, we’d like to gather a unique list of colors in that table. We can do that using the following syntax:







# Aliases
**Aliases** are temporary names used for tables and columns for queries within the database. They can be used to make certain columns or tables look easier to understand for the user or to keep the true identity of the column or table names a secret. It’s also beneficial to use aliases when writing complex queries, as it can simplify table and column names—thereforemaking the query-writing process quicker.

We can also create string aliases and non-string aliases from column or table names. It’s best practice to use the `AS` keyword after the column or table name to specify the alias because it makes the code easier to read. There are intended and accidental aliases; **intended** aliases are the ones we set using the `AS` keyword, and **accidental** aliases are written after the column name without the `AS` keyword. We can see this in the syntax below:




     

Learn the presentation of data through distinct, aliases, stored procedures, views, and top functions.

ProductID	ModVersion	Color	ModuleName	ModDescr	DatabaseIncl	UnitPrice
1	1.0	Red	Module A	Interface for using GIS maps	Yes	1000.00
2	1.0	Blue	Module B	Database system that allows them to enter spatial data	Yes	1500.00
3	1.0	Green	Module C	Email application that sends emails based on spatial preferences	No	750.00
4	1.0	Red	Module D	Hosting service for all modules	Yes	2500.00

Results
	Color
1	Red
2	Green
3	Blue

Introduction

Database Components

Structuring the Database

Data Retrieval

Data Definition

Data Manipulation

Transforming Data and Functions

Database Administration

Conclusion

Appendix

Data Presentation

Prod.Products Table

The `DISTINCT` function

Output of DINSTINCT

Aliases

Data Presentation

Prod.Products Table

The DISTINCT function

Output of DINSTINCT

Aliases

The `DISTINCT` function