Thursday, 26 June 2025

Data Types In PostgreSQL: Character Data Types || PostgreSQL Full Playli...


Welcome to Part 45 of our PostgreSQL Full Course Playlist! 🚀

In this video, we dive deep into one of the most fundamental aspects of PostgreSQL — Character Data Types. You'll learn the key differences, use cases, and behaviors of:

  • CHAR(n) – fixed-length, space-padded strings

  • VARCHAR(n) – variable-length strings with a defined limit

  • TEXT – flexible and unbounded character storage

  • Internal types like bpchar, "char", and name

🎯 We'll cover real-world examples like storing employee codes, customer names, blog content, product SKUs, and user feedback. You'll also learn the implications of trailing spaces, padding, truncation, and storage behavior.

💡 This session is crucial for anyone designing tables, optimizing storage, or simply trying to choose the best string type in PostgreSQL.

Whether you're a student, backend developer, or DBA — by the end of this video, you'll know when to use TEXT over VARCHAR, why CHAR can be risky, and how PostgreSQL handles string storage under the hood.

📌 Topics Covered:

  • Syntax & behavior of CHAR, VARCHAR, and TEXT

  • Storage internals (TOAST, compression, padding)

  • Behavior with trailing spaces

  • Comparison semantics and limitations

  • Best practices for choosing the right type

👉 Don't forget to like, comment, and subscribe for more deep-dive videos in this PostgreSQL series.

📽️ Next Video: Data Types In PostgreSQL – Binary Data Types

Friday, 20 June 2025

Data Types In PostgreSQL: Money Data Types || PostgreSQL Full Playlist V...


In this video (PostgreSQL Playlist #44), we take a deep dive into the money data type in PostgreSQL, which is specially designed to store and manipulate currency values with fixed fractional precision.

💡 You’ll learn:

  • What the money type is and how it works

  • How to create tables and insert monetary values

  • Type casting between money, numeric, and float

  • Performing arithmetic with money values

  • Real-world example: applying discounts on invoices

  • Best practices to avoid rounding errors and locale mismatches

🛠️ This tutorial is perfect for developers, data engineers, and students looking to enhance their PostgreSQL database design and financial data handling skills.

📌 Don’t forget to check out the complete PostgreSQL series for more in-depth tutorials.

Subscribe for more database and backend content, and hit the 🔔 to stay updated!

Wednesday, 11 June 2025

Data Types In PostgreSQL: Numeric Data Types || PostgreSQL Full Playlist...


In this video (Part #43 of the PostgreSQL Full Playlist), we take a deep dive into Numeric Data Types in PostgreSQL—an essential concept for every backend or data engineer. 🚀

You’ll learn how to handle real-world data like prices, tax rates, measurements, sensor data, population counts, and financial transactions using:

  • Integer Types: SMALLINT, INTEGER, BIGINT

  • Fixed Precision: NUMERIC, DECIMAL

  • Floating-Point: REAL, DOUBLE PRECISION

  • Auto-Increment Types: SERIAL, BIGSERIAL

  • Money Type: MONEY

  • Special values: Infinity, -Infinity, NaN

We also explore precision, rounding behavior, and common pitfalls—along with RETURNING clauses for instant verification. No more boring examples—every use case in this video is practical and relatable. 🧮💰

🔔 Don’t forget to Like, Subscribe, and Turn on Notifications to stay updated on this complete PostgreSQL tutorial series!

💬 Leave a comment below with your thoughts or questions!

Friday, 6 June 2025

Common Table Expressions - CTEs in PostgreSQL || How to Write CTEs || Po...


In this video, we dive deep into Common Table Expressions (CTEs) in PostgreSQL — a powerful feature that helps you write cleaner, more modular, and efficient SQL queries.

Whether you're a beginner exploring PostgreSQL or an advanced user refining your skills, this tutorial covers everything you need to know about WITH queries, including:

  • ✅ What is a CTE?

  • ✅ Syntax and structure

  • ✅ Benefits of using CTEs

  • ✅ Simple CTEs for temporary data sets

  • ✅ Recursive CTEs for generating sequences or traversing hierarchies

  • ✅ Data-Modifying CTEs using INSERT, UPDATE, and DELETE

  • ✅ Using CTEs with JOINs to simplify complex multi-table queries

  • ✅ Materialization and performance tips

You'll see real-time PostgreSQL examples that demonstrate how CTEs can be applied to real-world scenarios like summarizing data, cleaning up subqueries, and chaining modifications.

📌 This video is part of our PostgreSQL Full Playlist, where we guide you step-by-step from basic concepts to advanced performance optimizations.

💡 Don’t forget to like, comment, and subscribe to stay updated with more database content!

Tuesday, 3 June 2025

VALUES Lists in PostgreSQL Queries || Queries in PostgreSQL || PostgreSQ...


In this video of our PostgreSQL Full Playlist (#41), we take a deep dive into the VALUES clause—a powerful feature that lets you define temporary constant row sets without creating a real table.

We cover a variety of real-world scenarios, including:

  • Basic usage of the VALUES clause

  • Assigning column aliases

  • Using VALUES in INSERT statements (single and multiple rows)

  • Joining VALUES with real tables in the FROM clause

  • Performing bulk updates using VALUES and UPDATE together

  • Working with type casting, such as filtering IP addresses

  • Sorting and slicing result sets using ORDER BY, LIMIT, and OFFSET

Each example is practical, beginner-friendly, and designed to help you build solid SQL skills in PostgreSQL. Whether you're prepping for an interview or strengthening your database knowledge, this tutorial has something for everyone.

🔔 Don’t forget to like, comment, and subscribe to the channel for more hands-on PostgreSQL content.

👉 Next Video: WITH Queries (CTEs) in PostgreSQL

Friday, 30 May 2025

LIMIT and OFFSET in PostgreSQL Queries || Queries in PostgreSQL || Postg...


Welcome to Lesson #40 in our PostgreSQL Full Playlist! In this video, we explore the powerful LIMIT and OFFSET clauses in PostgreSQL and how they help control the number of rows returned from a query. Whether you're building a backend for a web app or optimizing your data reports, mastering these clauses is essential.

We begin by understanding the syntax of LIMIT and OFFSET, followed by real-world examples using an employees table. You’ll learn how to:

  • Return a specific number of rows

  • Skip rows using OFFSET

  • Combine both for pagination

  • Use ORDER BY to ensure consistent and predictable results

We’ll also walk through advanced techniques like using CTEs (Common Table Expressions) for more powerful and flexible pagination with ROW_NUMBER().

🔍 Performance Alert: Learn why high OFFSET values can hurt performance and how to implement keyset pagination for large datasets.

Perfect for students, backend developers, and data analysts who want clean, performant SQL!

📌 Chapters:
0:00 - Introduction
1:10 - What is LIMIT and OFFSET?
2:45 - Creating the Employees Table
4:20 - LIMIT Examples
6:00 - OFFSET Examples
7:00 - Pagination with LIMIT & OFFSET
8:00 - Real-World Pagination Scenario
9:20 - Performance Notes & Keyset Pagination
11:00 - Using CTEs with ROW_NUMBER
12:30 - Conclusion

💡 Subscribe and turn on notifications so you don’t miss the next video: VALUES Lists in PostgreSQL!

Wednesday, 28 May 2025

ORDER BY in PostgreSQL Queries || Sorting Rows in PostgreSQL || PostgreS...



Welcome to video #39 in our PostgreSQL Full Playlist! 🎬 In this tutorial, we dive deep into one of the most essential clauses in SQL: the ORDER BY clause.

You'll learn how to sort query results in PostgreSQL based on one or more columns, expressions, and aliases. We also explain how to handle NULL values using NULLS FIRST and NULLS LAST, sort using column positions, and apply ORDER BY in advanced cases such as UNION, CTEs, and window functions.

Whether you're preparing for interviews, writing production queries, or optimizing reports and dashboards, understanding ORDER BY is critical for clear and consistent output.

We demonstrate everything with real examples and walkthroughs, using a practical employees table. This lesson also includes tips on performance, index use, and sorting text data with collation.

🎯 Topics Covered:

  • Basic ascending and descending sorting

  • Sorting by expressions like salary + bonus

  • Handling NULLs explicitly

  • Using column aliases and positions in ORDER BY

  • ORDER BY with UNION, DISTINCT, and LIMIT/OFFSET

  • Sorting randomly with RANDOM()

  • Analytical queries using RANK() with OVER

  • Performance tips using EXPLAIN

Make sure to subscribe and check out the full PostgreSQL series for complete mastery! 🚀

📌 Stay tuned for the next episode: LIMIT and OFFSET in PostgreSQL Queries

Monday, 26 May 2025

Combining Queries in PostgreSQL || UNION, INTERSECT, EXCEPT || Best Post...


Welcome to another powerful episode of our PostgreSQL tutorial series! In Video #38, we dive deep into Combining Queries in PostgreSQL using the essential set operators: UNION, INTERSECT, and EXCEPT.

These operators are invaluable when working with multiple result sets. You'll learn:

  • How to combine query results with UNION and UNION ALL

  • How to find common records across result sets using INTERSECT

  • How to exclude records using EXCEPT

  • The importance of query compatibility and proper use of parentheses

  • How to retain or eliminate duplicates using the ALL keyword

  • Practical examples with Employees and Departments tables

We also cover operator precedence, the role of LIMIT and ORDER BY, and how subqueries and aliasing help you write cleaner, more accurate queries.

💡 Whether you're preparing for interviews, learning PostgreSQL for your job, or building data-driven apps, this tutorial is packed with hands-on examples and key tips that will help you query smarter and faster.

🔥 Don’t forget to like, subscribe, and hit the bell icon for more awesome database tutorials every week!

📌 Next up: Sorting Rows in PostgreSQL using ORDER BY!

Friday, 23 May 2025

Select Lists in PostgreSQL || Queries in PostgreSQL || Best PostgreSQL T...


🔍 Welcome to the Ultimate PostgreSQL Tutorial Series!
In this video (#37), we dive deep into one of the most crucial parts of any SQL query—the SELECT list. Whether you're a beginner or brushing up your database skills, this tutorial will guide you through the many ways PostgreSQL lets you customize the data you retrieve.

👨‍💻 What You'll Learn:

  • How to select all or specific columns

  • Using table aliases for cleaner queries

  • Creating computed columns with expressions

  • Renaming outputs with column aliases (AS)

  • Eliminating duplicates with DISTINCT and DISTINCT ON

  • Leveraging subqueries, functions, and CASE expressions

  • Working with JSON, arrays, and aggregate functions

  • Using LIMIT, OFFSET, and even SELECT without a FROM clause

  • Advanced techniques like CTEs (Common Table Expressions)

✨ With practical examples, best practices, and performance tips, this tutorial is your go-to guide for mastering SELECT lists in PostgreSQL!

🧠 Next Video: Combining Queries in PostgreSQL – UNION, INTERSECT, EXCEPT
👍 Don't forget to like, subscribe, and turn on notifications for more powerful PostgreSQL lessons.

Tuesday, 13 May 2025

Window Functions in PostgreSQL || Queries in PostgreSQL || Best PostgreS...


Welcome to another power-packed tutorial in our PostgreSQL series! 🚀 In Video #36, we dive deep into the world of Window Functions in PostgreSQL — an essential tool for writing analytical queries without losing row-level detail.

💡 Unlike regular aggregate functions, window functions let you calculate SUM, AVG, RANK, ROW_NUMBER, and moving averages over partitions of data while keeping every row visible. This opens up possibilities for advanced reporting, analytics, and insights directly within your SQL.

📊 We walk through real-world use cases with a sales table, showing step-by-step how to:

  • Calculate running totals and moving averages

  • Assign rankings and row numbers

  • Use LEAD and LAG for accessing prior/next rows

  • Work with PARTITION BY, ORDER BY, ROWS BETWEEN, and RANGE BETWEEN

  • Optimize performance with shared window specs and indexing tips

We even explore NTILE bucketing, filtered aggregations, and how to use GROUP BY alongside window functions.

Whether you're preparing for interviews, working on a data project, or just want to level up your SQL skills — this tutorial is packed with everything you need!

👉 Don’t forget to subscribe, like, and share if you find this helpful. Drop your questions in the comments, and stay tuned for the next video on Select Lists in PostgreSQL.

Happy Querying! 🧠💻

Monday, 5 May 2025

GROUPING SETS, ROLLUP, CUBE Clauses || Queries in PostgreSQL || Best Pos...



In this tutorial, we explore the powerful GROUPING SETS, ROLLUP, and CUBE clauses in PostgreSQL, which are essential for advanced data analysis and reporting. You'll learn how to: Use GROUPING SETS to calculate subtotals across different combinations of dimensions like region, category, and subcategory. Apply ROLLUP to create hierarchical totals—ideal for business summaries (e.g., region → category → subcategory). Use CUBE for full multidimensional aggregation—critical in business intelligence and OLAP scenarios. This video walks through real SQL examples using a sample sales_data table and demonstrates how these clauses simplify complex reporting tasks. If you're working with data warehouses, financial reports, or BI dashboards, mastering these techniques is a must! 👨‍💻 Whether you're a student, analyst, or backend developer, this PostgreSQL video will take your skills to the next level. 📌 Don’t forget to like, subscribe, and check out the full PostgreSQL series!

Tuesday, 1 April 2025

The GROUP BY And HAVING Clauses || Queries In PostgreSQL || Best Postgre...


Master the GROUP BY and HAVING clauses in PostgreSQL with real-world examples! 🚀 In this tutorial, we explore how GROUP BY helps in summarizing data and how HAVING filters the grouped results. These SQL clauses are crucial for data analysis, reporting, and decision-making. 🔹 What You’ll Learn in This Video? ✔️ How GROUP BY organizes data into meaningful groups ✔️ Using aggregate functions like SUM(), COUNT(), AVG() with GROUP BY ✔️ Applying HAVING to filter grouped results ✔️ Practical examples with employee salary analysis & online order revenue calculations 💻 Example Queries Used in This Video: 📌 Employee Salary Analysis Calculate total salary per department Count employees in each department 📌 Online Orders Revenue Analysis Find total revenue per product Filter high-revenue products using HAVING 📚 Sample Query – Total Revenue per Product SELECT product, SUM(quantity * price) AS total_revenue FROM orders GROUP BY product; 🔥 Ready to level up your SQL skills? Watch the full tutorial and practice along! 📢 Next Video: GROUPING SETS, CUBE, and ROLLUP in PostgreSQL 🔔 Subscribe for more PostgreSQL tutorials!

Saturday, 22 March 2025

The WHERE Clause In Table Expressions || Queries In PostgreSQL || Best P...


The WHERE clause in PostgreSQL is a powerful tool used to filter records based on specific conditions. It plays a crucial role in SQL queries by ensuring that only the necessary data is retrieved, leading to improved performance and efficiency. Whether you're working with SELECT, UPDATE, DELETE, or other SQL commands, understanding the WHERE clause is essential for effective database management.

🔹 What You'll Learn in This Video:
✅ Basic filtering with the WHERE clause
✅ Using IN, BETWEEN, and LIKE for advanced filtering
✅ Handling NULL values in WHERE conditions
✅ Combining WHERE with JOINs for optimized queries
✅ Applying logical operators (AND, OR, NOT) for precise conditions
✅ Using EXISTS and subqueries for powerful data selection

💡 SQL Examples Covered:
✔ Filtering employees based on salary and department
✔ Using subqueries to fetch relevant department data
✔ Checking if records exist in related tables
✔ Pattern matching with LIKE
✔ Filtering records based on date conditions

This tutorial includes practical examples using PostgreSQL, making it easy for beginners and advanced users to grasp the concepts. By mastering the WHERE clause, you can significantly improve your database queries and optimize data retrieval.

📌 Next Video: Queries in PostgreSQL – The GROUP BY and HAVING Clauses in PostgreSQL

📢 Don't forget to like, share, and subscribe for more PostgreSQL tutorials! 🚀

#PostgreSQL #SQLQueries #WHEREClause #DatabaseOptimization

Friday, 21 March 2025

The FROM Clause In Table Expressions || Queries In PostgreSQL || Best Po...


Understanding the FROM clause is crucial for writing efficient SQL queries in PostgreSQL. In this video, we’ll explore how the FROM clause works within table expressions and why it plays a vital role in retrieving, filtering, and joining data.

🔹 What You’ll Learn in This Video:

✔️ Basics of table expressions in PostgreSQL
✔️ Table inheritance and how it affects queries
✔️ CROSS JOIN, INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL OUTER JOIN
✔️ Using table and column aliases for better readability
✔️ Implementing subqueries within the FROM clause
✔️ Understanding LATERAL subqueries
✔️ Utilizing table functions to enhance data retrieval

🔹 Key Examples Covered:

✅ Creating and querying tables (employees and departments)
✅ Performing various types of joins to combine related data
✅ Using subqueries to simplify complex queries
✅ Writing functions to return sets of rows within the FROM clause

🚀 Why Watch This Video?

Whether you’re a beginner or an advanced PostgreSQL user, mastering the FROM clause will improve your database queries significantly. By the end of this tutorial, you'll be confident in handling table expressions, joins, and subqueries like a pro!

👉 Don't forget to LIKE 👍, COMMENT 💬, and SUBSCRIBE 🔔 for more PostgreSQL tutorials!

Thursday, 13 March 2025

Returning Data From Modified Rows In PostgreSQL || Best PostgreSQL Tutor...


In this video, we explore how to return data from modified rows using the RETURNING clause in PostgreSQL. PostgreSQL offers a powerful RETURNING clause with INSERT, UPDATE, DELETE, and MERGE commands that allows you to fetch data directly from affected rows without running an additional SELECT query.

The RETURNING clause is especially useful when working with auto-generated IDs (serial columns), computed columns, or trigger-influenced data, and helps in optimizing database interactions.

We will start by demonstrating INSERT statements with RETURNING, including how to fetch serial IDs and entire rows. Then, we cover UPDATE with RETURNING to get updated values in real-time, and DELETE with RETURNING to capture deleted rows for audit or logging purposes.

Moreover, you will learn how to combine MERGE with RETURNING for upsert operations, and how triggers interact with RETURNING to retrieve rows modified by triggers before final insertion.

Key Highlights of this video:

  • Syntax and usage of RETURNING clause.
  • Efficient way to fetch modified rows after DML operations.
  • Practical examples with INSERT, UPDATE, DELETE, MERGE.
  • How RETURNING works with trigger-modified data.
  • Real-time data retrieval without additional SELECT queries.

If you are working on PostgreSQL databases and want to optimize your data modification workflows, this video is for you! Watch till the end to fully master the RETURNING clause!

👉 Next Video: Table Expressions In PostgreSQL - The FROM Clause

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