Speeding Up Databases with Counter Caching, Claude AI and more ...

SQL tip, Database optimization, AI assistants #Edition 18

What’s on the list today?

• Database Deep Dive - Counter caching

• Keep up with AI - Claude

• SQL Tip - QUALIFY

⏰ Counter Caching

Ever wondered how websites instantly show "9,000 reviews" or "5,234 comments" without slowing down? Let's dive into Counter Caching!

Counter caching is a database optimization technique used to store and maintain a precomputed count of associated records in a separate column. This avoids the need to run expensive COUNT queries each time the count is needed, improving performance.

Let's take an e-commerce scenario. Without counter caching, here's what happens when showing product reviews:

-- Traditional approach (problematic)
SELECT COUNT(*) FROM reviews WHERE product_id = 123;

This means counting thousands of records ... EVERY. SINGLE. TIME.

Why is this a Problem?💥

Imagine a busy bookstore where staff counts every book on the shelves each time a customer asks "how many copies do you have?" Inefficient, right?

In other words this results in:

• Slow page loads during peak traffic

• Heavy database load

• Inconsistent performance

Enter Counter Caching ✨

Instead of counting repeatedly, we maintain running totals:

-- Products table with counter cache
CREATE TABLE products (
    id INT,
    name VARCHAR(255),
    review_count INT DEFAULT 0
);

When someone adds a review:

-- Update the review counter
UPDATE products 
SET review_count = review_count + 1 
WHERE id = 123;

Most modern implementations update counters asynchronously and combine with caching services like redis to make retrieval even faster.

The Impact 📈

• Instant metric display

• Minimal database impact

• Consistent performance

Counter caching transforms expensive counting operations into simple lookups. It's like keeping a running scoreboard instead of counting points after every game.

🤖 Keeping up with AI: Anthropic Claude

The rise of AI assistants is transforming our personal and professional lives. With new advancements happening daily, it's easy to feel overwhelmed. That's why we're bringing you a bite-sized overview of the latest AI updates – saving you time and effort while keeping you ahead of the curve.

Today lets talk about Claude AI

Claude AI is an AI assistant developed by Anthropic, a company dedicated to advancing AI safety and research. It’s similar to ChatGPT but is designed with a strong emphasis on being helpful, honest, and harmless through a method called constitutional AI.

Although I cannot comment on the ethical aspect, I do love some of its unique features.

Key features

Screenshot Share - This feature lets you share any window/tab on your screen and get instant feedback from Claude – a powerful tool for accelerated insight and decision-making.

Artefacts window - I wish many tools copied this feature. Claude has a neat little trick whenever the generated output gets slightly complex and longer, Claude simply pops up an interactive side window called the Artefacts window. Claude simply pushes all content of the answer into this window while explaining it on the original chat window. Especially useful where you are trying to get some code keeping the code separated from the explanation.

Claude Artefact window

Interactive dashboards

Imagine being an investor, bursting with excitement to dive into quarterly reports and uncover their secrets. But instead, you're met with a daunting wall of text: 50 pages of dense financial analysis, dense data tables, and endless technical jargon – exactly what you wanted to avoid.

Upload your quarterly report, and let Claude create a stunning visual dashboard that breaks down complex data into bite-sized insights. Suddenly, making sense of the numbers isn't just a chore – it's a breeze. How cool is that?"

Claude uses React components to create interactive and visually appealing dashboards, allowing you to easily explore and analyze the data within the artefact window.

Visual dashboard of Quarterly Results of a company

Give Claude a try and see how it can boost your daily productivity. Claude offers a free version, ideal for occasional use, and lets you get started without breaking the bank - literally! 💸

💡 Data Engineering Tip: SQL Qualify

One frequently overlooked yet valuable SQL tip that bears repeating is Qualify.

The QUALIFY clause simplifies filtering on window function results, eliminating the need for subqueries or common table expressions (CTEs).

--Without Qualify longer query
WITH ranked_orders AS (
    SELECT 
        customer_id, 
        order_id, 
        order_date, 
        ROW_NUMBER() OVER (PARTITION BY customer_id ORDER BY order_date DESC) AS rn
    FROM orders
)
SELECT * FROM ranked_orders WHERE rn = 1;

--With Qualify
SELECT 
    customer_id, 
    order_id, 
    order_date, 
    ROW_NUMBER() OVER (PARTITION BY customer_id ORDER BY order_date DESC) AS rn
FROM orders
QUALIFY rn = 1;

✅ More readable than using ROW_NUMBER() in a subquery

✅ Filters window function results directly

✅ Great for deduplication & ranking queries