PostgreSQL Tutorial

PostgreSQL Tutorial Welcome to the PostgreSQLTutorial.com website!

This PostgreSQL tutorial helps you quickly understand PostgreSQL. You’ll master PostgreSQL fast through many practical examples and apply the knowledge to application development using PostgreSQL.

If you want to:

Learn PostgreSQL fast.
Develop applications using PostgreSQL as the back-end database.
Migrate from other database management systems such as MySQL, Oracle, and Microsoft SQL Server.

You’ve come to the right place. This website provides you with everything you need to know to get started with PostgreSQL quickly and effectively.

The PostgreSQL tutorial demonstrates many unique features of PostgreSQL that position it as the most advanced open-source database management system.

Quick start

Getting Started with PostgreSQL

This section helps you get started with PostgreSQL by showing you how to install PostgreSQL on Windows, Linux, and macOS. You also learn how to connect to PostgreSQL using the psql tool as well as how to load a sample database into the PostgreSQL for practicing.## Basic PostgreSQL Tutorial

First, you’ll learn how to query data from a single table using basic data techniques, which include selecting data, sorting result sets, and filtering rows.

Next, you’ll delve into advanced queries, which include joining multiple tables, using set operations, and constructing the subquery.

Finally, you’ll learn how to manage database tables, including creating a new table or modifying the structure of an existing table.

Section 1. Querying Data

Select – show you how to query data from a single table.
Column aliases – learn how to assign temporary names to columns or expressions within a query.
Order By – guide you on how to sort the result set returned by a query.
Select Distinct – show you how to remove duplicate rows from the result set.

Section 2. Filtering Data

Where – filter rows based on a specified condition.
AND operator – combine two boolean expressions and return true if both expressions evaluate to true.
OR operator – combine two boolean expressions and return false if either expression evaluates to false.
Limit – retrieve a subset of rows generated by a query.
Fetch– limit the number of rows returned by a query.
In – select data that matches any value in a list of values.
Between – select data that is a range of values.
Like – filter data based on pattern matching.
Is Null – check if a value is null or not.

Section 3. Joining Multiple Tables

Joins – show you a brief overview of joins in PostgreSQL.
Table aliases – describes how to use table aliases in the query.
Inner Join– select rows from one table that have the corresponding rows in other tables.
Left Join – select rows from one table that may or may not have the corresponding rows in other tables.
Self-join – join a table to itself by comparing a table to itself.
Full Outer Join – use the full join to find a row in a table that does not have a matching row in another table.
Cross Join – produce a Cartesian product of the rows in two or more tables.
Natural Join – join two or more tables using implicit join conditions based on the common column names in the joined tables.

Section 4. Grouping Data

Group By – divide rows of a result set into groups and optionally apply an aggregate function to each group.
Having – apply conditions to groups, which allow you to filter groups.

Section 5. Set Operations

Union – combine result sets of multiple queries into a single result set.
Intersect – combine the result sets of two or more queries and return a single result set containing rows that appear in both result sets.
Except – return the rows from the first query that do not appear in the output of the second query.

Section 6. Grouping sets, Cubes, and Rollups

Grouping Sets – generate multiple grouping sets in reporting.
Cube – define multiple grouping sets that include all possible combinations of dimensions.
Rollup – generate reports that contain totals and subtotals.

Section 7. Subquery

Subquery – write a query nested inside another query.
Correlated Subquery – show you how to use a correlated subquery to perform a query that depends on the values of the current row being processed.
ANY – retrieve data by comparing a value with a set of values returned by a subquery.
ALL – query data by comparing a value with a list of values returned by a subquery.
EXISTS – check for the existence of rows returned by a subquery.

Section 8. Common Table Expressions

PostgreSQL CTE – introduce you to PostgreSQL common table expressions or CTEs.
Recursive query using CTEs – discuss the recursive query and learn how to apply it in various contexts.

Section 9. Modifying Data

In this section, you will learn how to insert data into a table with the INSERT statement, modify existing data with the UPDATE statement, and remove data with the DELETE statement. Additionally, you will learn how to use the UPSERT statement to merge data.

Insert – guide you on how to insert a single row into a table.
Insert multiple rows – show you how to insert multiple rows into a table.
Update – update existing data in a table.
Update join – update values in a table based on values in another table.
Delete – delete data in a table.
Upsert – insert or update data if the new row already exists in the table.

Section 10. Transactions

PostgreSQL Transactions – show you how to handle transactions in PostgreSQL using BEGIN, COMMIT, and ROLLBACK statements.

Section 11. Import & Export Data

You will learn how to import and export PostgreSQL data from and to CSV file format using the copy command.

Import CSV file into Table – show you how to import CSV file into a table.
Export PostgreSQL Table to CSV file – show you how to export tables to a CSV file.

Section 12. Managing Tables

In this section, you will begin exploring the PostgreSQL data types and learn how to create new tables and modify the structure of the existing ones.

Data types – cover the most commonly used PostgreSQL data types.
Create a table – guide you on how to create a new table in the database.
Select Into & Create table as– shows you how to create a new table from the result set of a query.
Auto-increment column with SERIAL – uses SERIAL to add an auto-increment column to a table.
Sequences – introduce you to sequences and describe how to use a sequence to generate a sequence of numbers.
Identity column – show you how to use the identity column.
Alter table – modify the structure of an existing table.
Rename table – change the name of the table to a new one.
Add column – show you how to add one or more columns to an existing table.
Drop column – demonstrate how to drop a column of a table.
Change column data type – show you how to change a column’s data.
Rename column – illustrate how to rename one or more table columns.
Drop table – remove an existing table and all of its dependent objects.
Truncate table – remove all data in a large table quickly and efficiently.
Temporary table – show you how to use the temporary table.
Copy a table – show you how to copy a table to a new one.

Section 13. PostgreSQL Constraints

Primary key – illustrate how to define a primary key when creating a table or adding a primary key to an existing table.
Foreign key – show you how to define foreign key constraints when creating a new table or adding foreign key constraints for existing tables.
DELETE CASCADE – show you how to automatically delete rows in child tables when the corresponding rows in the parent table are deleted.
CHECK constraint – add logic to check value based on a Boolean expression.
UNIQUE constraint – ensure that values in a column or a group of columns are unique across the table.
NOT NULL constraint – ensure values in a column are not NULL.
DEFAULT constraint – specify a default value for a column using the DEFAULT constraint.

Section 14. PostgreSQL Data Types in Depth

Boolean – store TRUE and FALSEvalues with the Boolean data type.
CHAR, VARCHAR, and TEXT – learn how to use various character types including CHAR, VARCHAR, and TEXT.
NUMERIC – show you how to use NUMERIC type to store values that precision is required.
DOUBLE PRECISION – learn to store inexact, variable-precision numbers in the database. The DOUBLE PRECISION type is also known as the FLOAT type.
REAL – guide you on how to use single-precision floating-point numbers in the database.
Integer – introduce you to various integer types in PostgreSQL including SMALLINT, INT and BIGINT.
DATE – introduce the DATE data type for storing date values.
Timestamp – understand timestamp data types quickly.
Interval – show you how to use interval data type to handle a period effectively.
TIME – use the TIME datatype to manage the time of day values.
UUID – guide you on how to use UUID datatype and how to generate UUID values using supplied modules.
Array – show you how to work with arrays and introduce you to some handy functions for array manipulation.
hstore – introduce you to the hstore data type, a set of key/value pairs stored in a single value in PostgreSQL.
JSON – illustrate how to work with JSON data type and use some of the most important JSON operators and functions.
User-defined data types – show you how to use the CREATE DOMAIN and CREATE TYPE statements to create user-defined data types.
Enum – learn how to create an enum type that defines a list of fixed values for a column.
XML – show you how to store XML documents in the database using the XML data type.
BYTEA – learn how to store binary strings in the database.
Composite Types – show you how to define a composite type that consists of multiple fields.

Section 15. Conditional Expressions & Operators

CASE – show you how to form conditional queries with CASE expression.
COALESCE – return the first non-null argument. You can use it to substitute NULL by a default value.
NULLIF – return NULL if the first argument equals the second one.
CAST – convert from one data type into another e.g., from a string into an integer, from a string into a date.

Section 16. PostgreSQL Utilities

psql commands – show you the most common psql commands that help you interact with psql faster and more effectively.

Section 17. PostgreSQL Recipes

How to compare two tables – describe how to compare data in two tables in a database.
How to delete duplicate rows in PostgreSQL – show you various ways to delete duplicate rows from a table.
How to generate a random number in a range – illustrate how to generate a random number in a specific range.
EXPLAIN statement– guide you on how to use the EXPLAIN statement to return the execution plan of a query.
PostgreSQL vs. MySQL – compare PostgreSQL with MySQL in terms of functionalities.

Advanced PostgreSQL Tutorial

This advanced PostgreSQL tutorial covers the advanced concepts including stored procedures, indexes, views, triggers, and database administrations.