20 Tutorials

Learn PostgreSQL

Master PostgreSQL from the basics to advanced topics like window functions, recursive queries, and full-text search.

Getting Started

How to Write a SELECT Statement in PostgreSQL

Learn the fundamentals of retrieving data from PostgreSQL tables using SELECT queries.

Beginner5 min read

Filtering Data with WHERE in PostgreSQL

Filter query results using comparison operators, LIKE patterns, IN lists, and BETWEEN ranges.

Beginner5 min read

Sorting Results with ORDER BY in PostgreSQL

Sort your query output by one or more columns in ascending or descending order.

Beginner4 min read

How to INSERT Data in PostgreSQL

Add single or multiple rows to a table, use RETURNING, and handle conflicts with ON CONFLICT.

Beginner5 min read

UPDATE and DELETE Rows in PostgreSQL

Modify and remove rows safely using UPDATE, DELETE, and the RETURNING clause.

Beginner5 min read

How to Create Tables in PostgreSQL

Define tables with columns, data types, primary keys, constraints, and default values.

Beginner6 min read

Understanding JOINs in PostgreSQL

Combine rows from multiple tables using INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN.

Beginner6 min read

Intermediate

GROUP BY and HAVING in PostgreSQL

Aggregate data into groups and filter grouped results with HAVING clauses.

Intermediate5 min read

Writing Subqueries in PostgreSQL

Use nested queries in SELECT, WHERE, and FROM clauses to build powerful multi-step queries.

Intermediate6 min read

PostgreSQL String Functions Guide

Manipulate text with CONCAT, SUBSTRING, TRIM, REPLACE, UPPER, LOWER, and regex functions.

Intermediate5 min read

Working with Dates in PostgreSQL

Handle dates and timestamps using NOW(), AGE(), EXTRACT(), DATE_TRUNC, and interval arithmetic.

Intermediate6 min read

How to Create and Use Indexes in PostgreSQL

Speed up queries with B-tree, GIN, GiST, and partial indexes, and learn when to use each.

Intermediate6 min read

Creating and Using Views in PostgreSQL

Simplify complex queries by saving them as reusable views, including materialized views.

Intermediate5 min read

How to Query JSON Columns in PostgreSQL

Extract and filter JSON/JSONB data using ->, ->>, jsonb_array_elements, and containment operators.

Intermediate6 min read

PostgreSQL Aggregate Functions (SUM, AVG, COUNT)

Summarize data with COUNT, SUM, AVG, MIN, MAX and combine them with GROUP BY for reporting.

Intermediate5 min read

Advanced

PostgreSQL Window Functions Tutorial

Perform calculations across related rows with ROW_NUMBER, RANK, LAG, LEAD, and custom frames.

Advanced7 min read

Common Table Expressions (CTEs) in PostgreSQL

Write readable, modular queries using WITH clauses and chain multiple CTEs together.

Advanced6 min read

Recursive Queries in PostgreSQL

Traverse hierarchical data like org charts and category trees using WITH RECURSIVE.

Advanced7 min read

PostgreSQL Query Performance Tuning

Read EXPLAIN ANALYZE output, identify bottlenecks, and apply index and query optimizations.

Advanced8 min read

Full-Text Search in PostgreSQL

Build search features using tsvector, tsquery, ranking functions, and GIN indexes.

Advanced7 min read

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