Introduction TO SQL
How to learn SQL | Roadmap to learning SQL
SQL Roadmap: A Complete Guide to Learning SQL
If you're looking to learn SQL for free, the first challenge is knowing where to start and what
concepts to learn. SQL has many different concepts, and different jobs require different levels
of expertise. Some may only need to learn basic SQL, while others may want to learn
advanced SQL to become a database developer or an SQL developer. This provides a
complete SQL roadmap with different concepts to learn based on your level of expertise and
the resources and platforms available to practise them.
Prerequisites: Understanding Relational Databases and Choosing an RDBMS
SQL is a programming language used to interact with relational databases. When building an
application or software, the data needed is generally stored in a relational database. The most
widely used RDBMS are Oracle, MySQL, Microsoft SQL Server, and PostgreSQL. However,
it does not matter which RDBMS you choose to learn SQL because most of the SQL used in
them is the same. If you learn SQL in one RDBMS, you will be able to apply it to any other
RDBMS. PostgreSQL is a free and lightweight database that is an excellent choice for
learning SQL.
After selecting an RDBMS, you need to install it and an IDE tool to connect to the database
and perform operations. Each RDBMS comes with its own IDE tool, such as SQL Developer
for Oracle, SQL Server Management Studio for Microsoft SQL Server, MySQL Workbench
for MySQL, and pgAdmin for PostgreSQL.
Learning Basic SQL: Concepts, Resources, and Practice
If you want to learn basic SQL, you need to first understand what a relational database is,
how data is stored in it, and what a schema is. You also need to know the different SQL
commands, such as DDL, DML, DCL, TCL, and DQL, and how they perform specific tasks.
Additionally, it's crucial to understand data types, constraints, normalisation, operators, and
clauses, and how to write inner joins.
To start learning, you can install a database like PostgreSQL or PGAdmin, watch tutorials,
and practice on platforms like Strata Scratch, LeetCode, and Data Lema. You can also use
resources like W3Schools to find syntax for different concepts.
Skills You Will Gain
● Understanding of relational databases and schemas
● Knowledge of SQL commands and their functions
● Familiarity with data types and constraints
● Ability to write inner joins and use operators and clauses
● Experience in practising on SQL platforms
,Resources for Learning Basic SQL
Syntax Resource: Use W3Schools to find syntax references for different SQL concepts.
Practice Platforms: Use Strata Scratch, LeetCode, and Data Lema to practise writing SQL
queries using basic concepts.
Job Opportunities
With basic SQL skills, you can target jobs like data analyst and business analyst.
Learning Basic SQL
If you want to learn basic SQL, there are various resources and platforms available. You can
start by learning basic SQL concepts such as creating tables, selecting data, filtering data, and
sorting data. Some of the platforms where you can practise solving SQL queries include
StrataScratch, LeetCode, and Data Lemer. Choose easy problems to solve and gradually
move on to more complex ones as you become more comfortable with the concepts. Basic
SQL knowledge is sufficient for business analyst roles, junior analyst roles, and software
engineers with up to three years of experience.
Learning Intermediate SQL
If you want to learn intermediate SQL, you should know group by and having clause,
aggregate functions, order of execution, subqueries, CTE tables or with clause, different types
of joins, inbuilt functions, window functions, and views. Some of the resources and platforms
where you can learn these concepts include W3Schools, tutorial videos, and SQL case studies
from Danny Data. For practising SQL queries, you can use StrataScratch, LeetCode, and
Data Lemer. Intermediate SQL knowledge is necessary for data analyst and data scientist
roles.
Jobs that Require SQL Knowledge
Basic SQL knowledge is sufficient for business analyst roles, junior analyst roles, and
software engineers with up to three years of experience. Intermediate SQL knowledge is
necessary for data analyst and data scientist roles.
Advanced SQL Knowledge
The jobs you can target with advanced SQL knowledge include data engineer or ATL
developer. Concepts you additionally need to learn include recursive SQL queries, pivot table
or crosstab, materialised views, stored procedures, and user-defined functions. Resources to
learn include tutorial videos on Youtube and a blog. Platforms to practise on include Status,
Scratch, LeetCode, and Data Lemur.
,Database Developer or SQL Developer
For the job of database developer or SQL developer, you need to learn about indexes,
triggers, temporary tables, dynamically executing an SQL statement, PL SQL concepts, and
performance tuning. Resources include blogs on indexes, triggers, temporary tables, dynamic
execution of SQL statements, PL SQL concepts, and performance tuning. There is no known
platform to practise these concepts.
Learn What is Database | Types of Database | DBMS
Understanding Databases: Types and Uses
Welcome to today's digital world where data is more valuable than ever before. Data is the
key to the smooth functioning of everything from a government to a local company. The
success of a company vastly depends on how well they utilise their data. This is where
databases come into the picture. You need a database to store data. In this blog, let's learn
what a database is and the different types of databases available today.
What is Data?
Data can be anything and everything. Any information or fact can be considered as data. Your
name, age, date of birth, house address, bank balance, the vehicle you drive, or even the food
that you eat can be considered as data. Details related to a school or a technology or statistics
or even mathematics can be considered as data and can be stored into a database. Data can be
in any form, such as an image or a video or a file or even plain text.
What is a Database?
A database can be considered as a container filled with data or information, which is
electronically stored in a computer system. Data in any form can be stored into the database.
The purpose of storing the data into the database is so it can be easily accessed, modified,
protected, and analysed.
Most websites or mobile applications today, such as Google, Instagram, WhatsApp, and
Facebook, already use databases to store data.
Where is Data Stored?
Data is stored in a database. Whenever you try to save, edit, or retrieve information through a
web application, the application connects to the database to store, modify, or extract the data.
The database is installed on the computer's hard drive or a large server for bigger applications
or bigger companies that need to store huge data.
, What is DBMS?
DBMS stands for Database Management System, which is a software used to manage your
database. You need DBMS to interact with the database to store, modify, retrieve, and protect
data. DBMS is also required to create, modify, and delete database users. Examples of DBMS
include MySQL, PostgreSQL, MongoDB, Neo4j, and Cassandra.
Types of Databases
The evolution of the database started in the 1960s when the first type of database was made,
which was the flat file database. Later on, came the hierarchical database and then the
network database. Both of these databases stored data through a parent-child relationship but
were incapable of storing complex data relationships, hence were soon replaced by the
relational database.
In today's world, there are mainly two popular database types: relational database and
non-relational database. As per the usage, over 74 percent of the databases used today are
relational databases, but due to the immense rising data usage over the past decade, mainly
due to social media platforms, non-relational databases have become very popular.
The biggest companies today who store data related to millions of users every day generally
use a combination of both relational and non-relational databases. Hence, both these database
types are very popular and widely used. Oracle is the most widely used relational database,
whereas MongoDB is the most widely used non-relational database.
Relational Database
In a relational database, data is stored through a collection of tables. These tables are related
to one another. Each table consists of columns and rows. Each column has a name and a data
type. A row can be treated as a record which is formed by single or multiple columns. Using
DBMS, you can enter commands in a specific language to store, retrieve, and modify data.
This specific language is SQL or Structured Query Language.
Examples of relational databases are Oracle, MySQL, Microsoft SQL Server, and
PostgreSQL.
Non-Relational Database
When it comes to a non-relational database, there are several categories of databases such as
key-value store, document database, graph database, wide column database, search engine
database, time-series database, etc.
How to learn SQL | Roadmap to learning SQL
SQL Roadmap: A Complete Guide to Learning SQL
If you're looking to learn SQL for free, the first challenge is knowing where to start and what
concepts to learn. SQL has many different concepts, and different jobs require different levels
of expertise. Some may only need to learn basic SQL, while others may want to learn
advanced SQL to become a database developer or an SQL developer. This provides a
complete SQL roadmap with different concepts to learn based on your level of expertise and
the resources and platforms available to practise them.
Prerequisites: Understanding Relational Databases and Choosing an RDBMS
SQL is a programming language used to interact with relational databases. When building an
application or software, the data needed is generally stored in a relational database. The most
widely used RDBMS are Oracle, MySQL, Microsoft SQL Server, and PostgreSQL. However,
it does not matter which RDBMS you choose to learn SQL because most of the SQL used in
them is the same. If you learn SQL in one RDBMS, you will be able to apply it to any other
RDBMS. PostgreSQL is a free and lightweight database that is an excellent choice for
learning SQL.
After selecting an RDBMS, you need to install it and an IDE tool to connect to the database
and perform operations. Each RDBMS comes with its own IDE tool, such as SQL Developer
for Oracle, SQL Server Management Studio for Microsoft SQL Server, MySQL Workbench
for MySQL, and pgAdmin for PostgreSQL.
Learning Basic SQL: Concepts, Resources, and Practice
If you want to learn basic SQL, you need to first understand what a relational database is,
how data is stored in it, and what a schema is. You also need to know the different SQL
commands, such as DDL, DML, DCL, TCL, and DQL, and how they perform specific tasks.
Additionally, it's crucial to understand data types, constraints, normalisation, operators, and
clauses, and how to write inner joins.
To start learning, you can install a database like PostgreSQL or PGAdmin, watch tutorials,
and practice on platforms like Strata Scratch, LeetCode, and Data Lema. You can also use
resources like W3Schools to find syntax for different concepts.
Skills You Will Gain
● Understanding of relational databases and schemas
● Knowledge of SQL commands and their functions
● Familiarity with data types and constraints
● Ability to write inner joins and use operators and clauses
● Experience in practising on SQL platforms
,Resources for Learning Basic SQL
Syntax Resource: Use W3Schools to find syntax references for different SQL concepts.
Practice Platforms: Use Strata Scratch, LeetCode, and Data Lema to practise writing SQL
queries using basic concepts.
Job Opportunities
With basic SQL skills, you can target jobs like data analyst and business analyst.
Learning Basic SQL
If you want to learn basic SQL, there are various resources and platforms available. You can
start by learning basic SQL concepts such as creating tables, selecting data, filtering data, and
sorting data. Some of the platforms where you can practise solving SQL queries include
StrataScratch, LeetCode, and Data Lemer. Choose easy problems to solve and gradually
move on to more complex ones as you become more comfortable with the concepts. Basic
SQL knowledge is sufficient for business analyst roles, junior analyst roles, and software
engineers with up to three years of experience.
Learning Intermediate SQL
If you want to learn intermediate SQL, you should know group by and having clause,
aggregate functions, order of execution, subqueries, CTE tables or with clause, different types
of joins, inbuilt functions, window functions, and views. Some of the resources and platforms
where you can learn these concepts include W3Schools, tutorial videos, and SQL case studies
from Danny Data. For practising SQL queries, you can use StrataScratch, LeetCode, and
Data Lemer. Intermediate SQL knowledge is necessary for data analyst and data scientist
roles.
Jobs that Require SQL Knowledge
Basic SQL knowledge is sufficient for business analyst roles, junior analyst roles, and
software engineers with up to three years of experience. Intermediate SQL knowledge is
necessary for data analyst and data scientist roles.
Advanced SQL Knowledge
The jobs you can target with advanced SQL knowledge include data engineer or ATL
developer. Concepts you additionally need to learn include recursive SQL queries, pivot table
or crosstab, materialised views, stored procedures, and user-defined functions. Resources to
learn include tutorial videos on Youtube and a blog. Platforms to practise on include Status,
Scratch, LeetCode, and Data Lemur.
,Database Developer or SQL Developer
For the job of database developer or SQL developer, you need to learn about indexes,
triggers, temporary tables, dynamically executing an SQL statement, PL SQL concepts, and
performance tuning. Resources include blogs on indexes, triggers, temporary tables, dynamic
execution of SQL statements, PL SQL concepts, and performance tuning. There is no known
platform to practise these concepts.
Learn What is Database | Types of Database | DBMS
Understanding Databases: Types and Uses
Welcome to today's digital world where data is more valuable than ever before. Data is the
key to the smooth functioning of everything from a government to a local company. The
success of a company vastly depends on how well they utilise their data. This is where
databases come into the picture. You need a database to store data. In this blog, let's learn
what a database is and the different types of databases available today.
What is Data?
Data can be anything and everything. Any information or fact can be considered as data. Your
name, age, date of birth, house address, bank balance, the vehicle you drive, or even the food
that you eat can be considered as data. Details related to a school or a technology or statistics
or even mathematics can be considered as data and can be stored into a database. Data can be
in any form, such as an image or a video or a file or even plain text.
What is a Database?
A database can be considered as a container filled with data or information, which is
electronically stored in a computer system. Data in any form can be stored into the database.
The purpose of storing the data into the database is so it can be easily accessed, modified,
protected, and analysed.
Most websites or mobile applications today, such as Google, Instagram, WhatsApp, and
Facebook, already use databases to store data.
Where is Data Stored?
Data is stored in a database. Whenever you try to save, edit, or retrieve information through a
web application, the application connects to the database to store, modify, or extract the data.
The database is installed on the computer's hard drive or a large server for bigger applications
or bigger companies that need to store huge data.
, What is DBMS?
DBMS stands for Database Management System, which is a software used to manage your
database. You need DBMS to interact with the database to store, modify, retrieve, and protect
data. DBMS is also required to create, modify, and delete database users. Examples of DBMS
include MySQL, PostgreSQL, MongoDB, Neo4j, and Cassandra.
Types of Databases
The evolution of the database started in the 1960s when the first type of database was made,
which was the flat file database. Later on, came the hierarchical database and then the
network database. Both of these databases stored data through a parent-child relationship but
were incapable of storing complex data relationships, hence were soon replaced by the
relational database.
In today's world, there are mainly two popular database types: relational database and
non-relational database. As per the usage, over 74 percent of the databases used today are
relational databases, but due to the immense rising data usage over the past decade, mainly
due to social media platforms, non-relational databases have become very popular.
The biggest companies today who store data related to millions of users every day generally
use a combination of both relational and non-relational databases. Hence, both these database
types are very popular and widely used. Oracle is the most widely used relational database,
whereas MongoDB is the most widely used non-relational database.
Relational Database
In a relational database, data is stored through a collection of tables. These tables are related
to one another. Each table consists of columns and rows. Each column has a name and a data
type. A row can be treated as a record which is formed by single or multiple columns. Using
DBMS, you can enter commands in a specific language to store, retrieve, and modify data.
This specific language is SQL or Structured Query Language.
Examples of relational databases are Oracle, MySQL, Microsoft SQL Server, and
PostgreSQL.
Non-Relational Database
When it comes to a non-relational database, there are several categories of databases such as
key-value store, document database, graph database, wide column database, search engine
database, time-series database, etc.
