Introduction to SQl for Data Analysis
Tags: sql, database, datascience, beginners
Published: 2023-02-17 08:19:22

 Structured query language is a standard programming language designed  in 1970s for accessing, manipulating and storing data in a relational database.As the name suggests, a relational database is a database composed of data organized in tables that relate to each other. The table rows and columns represent data characteristics and how the data values relate to each other.

**Why is SQl so important?
**
SQL is very easy to learn since it uses common English keywords like "where" in it's statements.
SQL is the most universal language in the world.It is  used in almost all types of  applications because it integrates so well with many programming languages.
It is the standard language for database management systems used in both extremely big and small businesses. 
SQL is a powerful,fast, efficient,secure, inexpensive open source  software that can be used to do anything related to a database.

**How SQL works**

When a query is run it is processed by a query optimizer.Upon reaching the SQL server,the query is  compiled in three stages:
a) parsing-syntax checking
b) binding-semantics checking 
c) optimization-query execution plan creation

**SQL Commands**

**Data Definition Language**:the creation,design and modification of the database structure and objects i.e the CREATE command 

**Data Query Language**: retrieval of data from the database for example the SELECT command 

**Data Manipulation Language:** insertion of new records and modification of existing ones i.e the INSERT command 

**Data Control Language:**access authorization of the database for example the GRANT command  to allow a given user to access a particular section of the database.

**Transaction Control Language**: automatic database changes i.e ROLLBACK command 

**SQL For Data Analysis**

Data Analysis,Data Science, Business Intelligence,Big Data etc all manipulate and process big amounts of data using different methods to gain 
useful  insights.
As mentioned earlier SQL can be implemented in all database management systems like desktop (Access),open source (MySQL) and commercial (oracle).
Data Analysts use SQL to process, manipulate and generally interact with data stored in relational databases.
Businesses and Organizations need Data analysts to discover useful patterns and trends from their data.
Data Analysis therefore involves collecting and organizing data to extract  and retrieve useful information that can be used to make critical decisions.
SQL offer great ability to data manipulation of big amounts of data.It can efficiently build complex models and analysis in a very short time.

**How to use SQL for Data Analysis **

Due to the SQL ability to communicate complex instructions to the database and manipulate data in the shortest time possible, SQL can be used to create useful dashboards with reporting tools that can display data in many ways.
Furthermore,SQL can be used to design and build useful warehouses.
SQL can be intergrated with different data analytics frameworks and Languages like python,R, Scala etc.

**Learning SQL for data analysis **

SQL is easy to learn ad use.Sometimes having just an SQL cheat sheet can get a data analyst get going.However, to be a better Data Analysts ,one need to exhaust SQL and master all the skills.

Finally, data analysts do analyze data but before that they need to retrieve it from the database and that's when SQL come in.Therefore, SQL is a critical language in data analysis.