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What is PostgreSQL - Introduction
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PostgreSQL Tutorial

Last Updated : 19 Jun, 2024
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In this PostgreSQL tutorial you’ll learn the basic data types(Boolean, char, text, time, int etc.), Querying and Filtering techniques like select, where, in, order by, etc. managing and modifying the tables in PostgreSQL. We’ll cover all the basic to advance concepts of PostgreSQL in this tutorial. So if you are beginner who start to learn RDBMS or an expert who want to upscale you PostgreSQL skills, then keep reading this free PostgreSQL tutorial.

PostgreSQL is one of the most advanced Relational database management systems (RDBMS). It is open-source software, which means the source code is available under the PostgreSQL license. Anyone with the right skills is free to use, modify, and distribute PostgreSQL in any form. It supports both relational as well as Non-Relational JSON Queries.

PostgreSQL Tutorial

What is PostgreSQL?

PostgreSQL is an advanced and open-source relational database management system and is used as a database for many web applications, mobile and analytics applications. It supports both SQL (relational) and JSON (non-relational) querying and It is a stable database supported by more than 20 years of development by the open-source community.

What is the Use of PostgreSQL?

As you know that PostgreSQL is a powerful, open-source relational database management system. It’s used Which is mostly use for storing, organizing, and retrieving data. Other then this things it is also widely used for:

  • Data Storage: It stores data in an organized way using tables, making it easy to manage large amounts of information.
  • Complex Queries: PostgreSQL supports complex queries, allowing you to fetch specific data using SQL (Structured Query Language).
  • ACID Compliance: It ensures reliable transactions with ACID (Atomicity, Consistency, Isolation, Durability) compliance, meaning your data remains accurate and secure.
  • Scalability: Suitable for both small and large applications, PostgreSQL can handle a large number of users and large datasets.
  • Extensibility: You can add custom functions, data types, and extensions, making PostgreSQL highly flexible and adaptable to various needs.
  • Support for Advanced Data Types: It supports advanced data types like JSON, XML, and arrays, allowing for diverse data storage and manipulation.

Table of Content

  • What is PostgreSQL?
  • PostgreSQL Basics
  • Data Types
  • Querying & Filtering Data
  • Managing Tables
  • Modifying Data
  • Conditionals
  • Control Flow
  • Transactions & Constraints
  • Working with JOINS & Schemas
  • Roles & Permissions
  • Working with Sets
  • Subquery & CTEs
  • User-Defined Functions
  • Important In-Built Functions
  • PostgreSQL PL/pgSQL
  • Variables & Constants
  • Stored Procedures
  • Working with Triggers
  • Working with Views & Indexes
  • Errors & Exception Handling
  • Features of PostgreSQL
  • Advantages of PostgreSQL

PostgreSQL Tutorial For Beginners

In this begineer section, you'll learn the basics, from installing PostgreSQL to creating your first database and running simple queries. We'll guide you step-by-step through setting up tables, inserting data, and retrieving information using SQL commands.

PostgreSQL Basics

Explore all the basics topics that every one know while learning the PostgreSQL, Here in this section you will learn introduction of PostgreSQL, how to install PostgreSQL on various OS and other PostgreSQL basics.

  • PostgreSQL - Introduction
  • Install PostgreSQL on Windows
  • Install PostgreSQL on Mac
  • PostgreSQL – Loading a Database
  • PostgreSQL - Create Database
  • PostgreSQL - ALTER DATABASE
  • PostgreSQL - DROP DATABASE
  • PostgreSQL - Rename Database
  • PostgreSQL - Copy Database
  • PostgreSQL - Size of a Database
  • PostgreSQL - Show Databases

Data Types

  • PostgreSQL – Data Types
  • PostgreSQL - Boolean Data Type
  • PostgreSQL - CHAR Data Type
  • PostgreSQL - VARCHAR Data Type
  • PostgreSQL - TEXT Data Type
  • PostgreSQL - NUMERIC Data Type
  • PostgreSQL - SMALLINT Integer Data Type
  • PostgreSQL - INTEGER Data Type
  • PostgreSQL - BIGINT Integer Data Type
  • PostgreSQL - Date Data Type
  • PostgreSQL - Timestamp Data Type.
  • PostgreSQL - UUID Data Type
  • PostgreSQL - TIME Data Type
  • PostgreSQL - Interval Data Type
  • PostgreSQL - User-defined Data Type
  • PostgreSQL - Array Data Type
  • PostgreSQL - hstore Data Type
  • PostgreSQL - JSON Data Type

Querying & Filtering Data

  • PostgreSQL – SELECT
  • PostgreSQL – SELECT DISTINCT clause
  • PostgreSQL – ORDER BY clause
  • PostgreSQL – WHERE clause
  • PostgreSQL – LIMIT clause
  • PostgreSQL – FETCH clause
  • PostgreSQL – IN operator
  • PostgreSQL – IS NULL operator
  • PostgreSQL – LIKE operator
  • PostgreSQL – NOT LIKE operator
  • PostgreSQL – BETWEEN operator
  • PostgreSQL – HAVING clause
  • PostgreSQL – GROUP BY clause

Managing Tables

  • PostgreSQL - CREATE TABLE
  • PostgreSQL - SELECT INTO
  • PostgreSQL - Create Auto-increment Column using SERIAL
  • PostgreSQL - CREATE SEQUENCE
  • PostgreSQL - Identity Column
  • PostgreSQL - ALTER TABLE
  • PostgreSQL - Rename Table
  • PostgreSQL - ADD COLUMN
  • PostgreSQL - DROP COLUMN
  • PostgreSQL - Change Column Type
  • PostgreSQL - RENAME COLUMN
  • PostgreSQL - DROP TABLE
  • PostgreSQL - TRUNCATE TABLE
  • PostgreSQL - Temporary Table
  • PostgreSQL - Temporary table name
  • PostgreSQL - Removing Temporary Table
  • PostgreSQL - Copy a Table
  • PostgreSQL - Comparing Tables
  • PostgreSQL - Describe Table
  • PostgreSQL - Show Tables
  • PostgreSQL – Import CSV File Into Table

Modifying Data

  • PostgreSQL – INSERT
  • PostgreSQL - Insert multiple rows
  • PostgreSQL – UPDATE
  • PostgreSQL - DELETE
  • PostgreSQL - Upsert

Conditionals

  • PostgreSQL - CASE
  • PostgreSQL - COALESCE
  • PostgreSQL - NULLIF() Function
  • PostgreSQL - CAST

Control Flow

  • PostgreSQL - IF Statement
  • PostgreSQL - CASE Statement
  • PostgreSQL - Loop Statement
  • PostgreSQL - While Loops
  • PostgreSQL - For Loops
  • PostgreSQL - Exit
  • PostgreSQL - Continue

Transactions & Constraints

  • PostgreSQL - Transactions
  • PostgreSQL - COMMIT
  • PostgreSQL - BEGIN
  • PostgreSQL - ROLLBACK
  • PostgreSQL - Primary Key
  • PostgreSQL - Foreign Key
  • PostgreSQL - CHECK Constraint
  • PostgreSQL - UNIQUE Constraint
  • PostgreSQL - NOT NULL Constraint

Working with JOINS & Schemas

  • PostgreSQL – Joins
  • PostgreSQL – LEFT JOIN
  • PostgreSQL – INNER JOIN
  • PostgreSQL – FULL OUTER JOIN
  • PostgreSQL – SELF JOIN
  • PostgreSQL - Schema
  • PostgreSQL - CREATE SCHEMA
  • PostgreSQL - DROP SCHEMA
  • PostgreSQL - ALTER SCHEMA

Roles & Permissions

  • PostgreSQL - CREATE ROLE
  • PostgreSQL - ALTER ROLE
  • PostgreSQL - DROP ROLE
  • PostgreSQL - GRANT
  • PostgreSQL - REVOKE
  • PostgreSQL - Role Membership

Working with Sets

  • PostgreSQL – UNION operator
  • PostgreSQL – INTERSECT Operator
  • PostgreSQL – EXCEPT Operator
  • PostgreSQL – GROUPING SETS
  • PostgreSQL – CUBE
  • PostgreSQL – ROLLUP

Subquery & CTEs

  • PostgreSQL – ANY Operator
  • PostgreSQL – ALL Operator
  • PostgreSQL – EXISTS Operator
  • PostgreSQL – CTE
  • PostgreSQL - Deleting Duplicate Rows using Subquery

User-Defined Functions

  • PostgreSQL - CREATE FUNCTION Statement
  • PostgreSQL - Function parameter modes
  • PostgreSQL - Function Overloading
  • PostgreSQL - Function that returns table
  • PostgreSQL - Drop Function

Important In-Built Functions

  • PostgreSQL - AVG() Function
  • PostgreSQL - COUNT() Function
  • PostgreSQL - MAX() Function
  • PostgreSQL - MIN() Function
  • PostgreSQL - SUM() Function
  • PostgreSQL - FIRST_VALUE Function
  • PostgreSQL - LAST_VALUE Function
  • PostgreSQL - NTH_VALUE Function
  • PostgreSQL - ROW_NUMBER Function
  • PostgreSQL - CURRENT_DATE Function
  • PostgreSQL - CURRENT_TIME Function
  • PostgreSQL - EXTRACT Function
  • PostgreSQL- CONCAT Function
  • PostgreSQL - FORMAT Function
  • PostgreSQL - UPPER function
  • PostgreSQL- LOWER function
  • PostgreSQL - REGEXP_MATCHES Function
  • PostgreSQL - REGEXP_REPLACE Function
  • PostgreSQL - REPLACE Function

Visit PostgreSQL In-Built functions for more.

Advanced PostgreSQL Tutorial

In this section, you'll learn about advanced features of PostgreSQL that can help you manage your databases more efficiently. We'll cover topics like performance tuning, indexing strategies, and using advanced SQL functions. You'll also explore how to handle large datasets, optimize queries, and set up replication for high availability.

PostgreSQL PL/pgSQL

  • PostgreSQL - Dollar-Quoted String Constants
  • PostgreSQL - Block Structure

Variables & Constants

  • PostgreSQL - Variables
  • PostgreSQL - Select Into
  • PostgreSQL - Row type variables
  • PostgreSQL - Record type variable
  • PostgreSQL - Constants

Stored Procedures

  • PostgreSQL - Introduction to Stored Procedures
  • PostgreSQL - CREATE PROCEDURE
  • PostgreSQL - Drop Procedure

Working with Triggers

  • PostgreSQL – Trigger
  • PostgreSQL - CREATE TRIGGER
  • PostgreSQL - DROP TRIGGER
  • PostgreSQL - ALTER TRIGGER
  • PostgreSQL - Disabling a Trigger
  • PostgreSQL - Enabling a Trigger

Working with Views & Indexes

  • PostgreSQL - CREATE INDEX
  • PostgreSQL - DROP INDEX
  • PostgreSQL - List Indexes
  • PostgreSQL - UNIQUE Index
  • PostgreSQL - Partial Index
  • PostgreSQL - Index On Expression
  • PostgreSQL - REINDEX
  • PostgreSQL - Multicolumn Indexes

Errors & Exception Handling

  • PostgreSQL - Errors and Messages
  • PostgreSQL - Exception Handling
  • PostgreSQL - Assert

Difference Between PostgreSQL and MySQL

FeaturePostgreSQLMySQL
TypeObject-relational databaseRelational database
ACID ComplianceFully ACID compliantFully ACID compliant
Complex QueriesExcellent support for complex queriesGood support for complex queries
Data TypesWide range of advanced data typesBasic range of data types
JSON SupportStrong support for JSONGood support for JSON
PerformanceGreat for complex, read-heavy operationsFast for read-heavy and write-heavy loads
ExtensibilityHighly extensible with custom functionsLimited extensibility
ReplicationSupports various replication methodsSupports master-slave replication
Community and SupportStrong community, active developmentStrong community, widely used
UsagePreferred for complex applicationsPreferred for web applications
LicenseOpen-source (PostgreSQL License)Open-source (GPL License)

Features of PostgreSQL

PostgreSQL runs on all operating systems, Like Linux, UNIX, MAC OS and Windows and It supports text, images, sounds, and video, and includes programming interfaces for C / C++, Java, Perl, Python, Ruby, and Open Database Connectivity (ODBC).

PostgreSQL supports a big part of the SQL standard and provides many features mentioned below:

  • Complex SQL queries
  • SQL Sub-selects
  • Foreign keys
  • Trigger
  • Views
  • Transactions
  • Multiversion concurrency control (MVCC)
  • Streaming Replication (as of 9.0)
  • Hot Standby (as of 9.0)
  • Asynchronous replication
  • Tablespaces

Advantages of PostgreSQL

  • PostgreSQL has the feature of write-ahead logging.
  • Many replication methods are supported.
  • It has ability to make large-scale web applications because it is robust and powerful.
  • It is easy to learn.
  • According to the organization we can edit and modify it easily because PostgreSQL is available for free to its open source license.

Conclusion

In this PostgreSQL tutorial, You will learn all the essentials of working with PostgreSQL Like installation, connecting to the database, creating and managing databases, SQL basics, querying data, advanced queries and joins, indexing and optimization, transactions and concurrency control, security and user management, backup and restore, PostGIS for geospatial data, and PostgreSQL extensions. PostgreSQL provides number of features Which makes it a versatile and reliable choice for building robust database-driven applications.


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What is PostgreSQL - Introduction
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    In PostgreSQL, the EXIT statement is a powerful tool used to terminate loops and blocks of code. This functionality is essential for managing control flow within your PostgreSQL scripts, allowing for more efficient and readable code. Let us get a better understanding of the usage of the EXIT stateme
    3 min read
    PostgreSQL - Continue
    The CONTINUE statement in PostgreSQL is used to prematurely skip the current iteration of a loop and proceed directly to the next iteration. This functionality applies to all types of loops, including unconditional loops, WHILE loops, and FOR loops.Let us get a better understanding of the CONTINUE s
    3 min read

    Transactions & Constraints

    PostgreSQL - Transactions
    A transaction in database terminology is not a new concept. Similar to familiar terms such as "cash transaction" in banking, a transaction in the context of databases like PostgreSQL is a unit of work that ensures data integrity and consistency. Transactions are fundamental when you need to add, del
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    PostgreSQL - COMMIT
    The COMMIT command in PostgreSQL is important for saving the changes made during a transaction. Without executing a COMMIT, all the data manipulation operations performed within the transaction will be lost once the session ends. It ensures that the changes made to the database are permanent and vis
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    PostgreSQL - Primary Key
    A primary key in PostgreSQL is a column (or a set of columns) that uniquely identifies each row in a table. It is an important component for ensuring data integrity and plays an important role in database normalization. When we define a primary key in PostgreSQL, the database automatically creates a
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    PostgreSQL - Foreign Key
    Foreign keys play a crucial role in relational databases by establishing relationships between tables and safeguarding data integrity. In this PostgreSQL foreign key tutorial, we'll cover how foreign keys work, their importance and how to create them. We will also learn about foreign key constraints
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    PostgreSQL - CHECK Constraint
    In PostgreSQL, the CHECK constraint is a powerful tool used to enforce data integrity by specifying that a value in a column must meet a specific requirement. The CHECK constraint uses a Boolean expression to evaluate the values before performing an insert or update operation on the column. If the v
    2 min read
    PostgreSQL - UNIQUE Constraint
    In PostgreSQL, the UNIQUE constraint is a powerful tool used to ensure that values stored in a column or a group of columns are unique across rows in a table. This constraint is essential for maintaining data integrity, especially when certain data should not be duplicated. For instance, if you're s
    3 min read
    PostgreSQL - NOT NULL Constraint
    In PostgreSQL, the NOT NULL constraint is a fundamental feature to ensure that a column cannot contain NULL values. NULL represents unknown or missing information in databases, distinct from an empty string or the number zero. For example, if you ask someone for their email address and they don’t kn
    3 min read

    JOINS & Schemas

    PostgreSQL - Joins
    The PostgreSQL JOIN statement is a powerful tool for combining data or rows from one or more tables based on a common field between them. These common fields are typically the primary key in the first table and the foreign key in the other table(s). By using different types of JOINs, we can perform
    5 min read
    PostgreSQL - LEFT JOIN
    In PostgreSQL, the LEFT JOIN (or LEFT OUTER JOIN) is a powerful tool that allows you to merge data from two tables based on a related column. With a LEFT JOIN, you get all records from the "left" table and matching records from the "right" table. If there’s no match in the right table, NULL values w
    5 min read
    PostgreSQL - INNER JOIN
    In PostgreSQL the INNER JOIN keyword selects all rows from both the tables as long as the condition satisfies. This keyword will create the result-set by combining all rows from both the tables where the condition satisfies i.e value of the common field will be the same. Syntax: SELECT table1.column
    2 min read
    PostgreSQL - FULL OUTER JOIN
    In PostgreSQL, the FULL OUTER JOIN is a powerful feature that combines the effects of both LEFT JOIN and RIGHT JOIN. This join operation retrieves all rows from both tables involved in the join, including unmatched rows from each table. For any unmatched rows, PostgreSQL fills the result with NULL v
    4 min read
    PostgreSQL - SELF JOIN
    In PostgreSQL, a SELF JOIN is a powerful technique that allows us to join a table with itself. This type of join is particularly useful for comparing rows within the same table, such as establishing hierarchical relationships or identifying duplicate records. Unlike other joins, there is no specific
    4 min read
    PostgreSQL - Schema
    PostgreSQL is a powerful, open-source relational database management system (RDBMS) that is widely used for managing data. One of the most important concepts in PostgreSQL is the schema. A schema is a way of organizing database objects like tables, views, indexes, functions, and data types. In this
    5 min read
    PostgreSQL - CREATE SCHEMA
    PostgreSQL provides the CREATE SCHEMA statement to create a new schema in a database. By creating schemas, users can effectively separate data into logical groups, making it easier to manage and access information. Schemas also enhance security by controlling object visibility and permissions, allow
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    PostgreSQL - DROP SCHEMA
    PostgreSQL offers a powerful schema management system, allowing database administrators to organize and manage objects within specific schemas. The DROP SCHEMA statement in PostgreSQL provides a straightforward way to delete entire schemas and the associated objects, making it a valuable tool for da
    4 min read
    PostgreSQL - ALTER SCHEMA
    In PostgreSQL, the ALTER SCHEMA statement is a powerful tool that allows you to modify the definition of an existing schema. By understanding how to use ALTER SCHEMA effectively is crucial for managing your database schemas. This article will provide a detailed exploration of the ALTER SCHEMA statem
    3 min read
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