Oracle COUNT(*) Optimization — Using Index Fast Full Scan

 

When developing applications, there are times when you need to quickly check whether certain data exists in a table. 

The most common method is using COUNT(), but this can be optimized for much better performance. 

Today, we’ll explore how to speed up COUNT() in Oracle using Index Fast Full Scan.

1. COUNT(*) Execution Methods

When performing COUNT(*), Oracle can scan data in two ways:

• Full Table Scan

• Full Index Scan

The faster method depends on the table structure and data distribution. Although scanning the index is often faster, Single Block Scan can sometimes limit the performance. What if we use Multi Block Scan for the index area? We can achieve significantly better speed.

2. What is Index Fast Full Scan?

Index Fast Full Scan reads the index area in parallel by dividing it into multiple blocks. Using this method, you can quickly perform COUNT(*) without directly reading the table’s data. For this, Oracle provides the INDEX_FFS hint.

3. Execution Plan Comparison

Basic COUNT(*) Execution

SELECT COUNT(*) FROM EMP;
Execution Plan
------------------------------------------------------------------
0        SELECT STATEMENT Optimizer=CHOOSE
1        0  SORT  (AGGREGATE)
2        1    TABLE ACCESS (FULL) OF ‘EMP’

Using Full Index Scan

SELECT /*+ INDEX(EMP pk_emp) */ COUNT(*) FROM EMP;
Execution Plan
------------------------------------------------------------------
0        SELECT STATEMENT Optimizer=CHOOSE
1        0  SORT  (AGGREGATE)
2        1    INDEX FULL SCAN OF ‘pk_emp’ (UNIQUE) (cost=30)

Using Index Fast Full Scan

SELECT /*+ INDEX_FFS(EMP pk_emp) */ COUNT(*) FROM EMP;
Execution Plan
------------------------------------------------------------------
0        SELECT STATEMENT Optimizer=CHOOSE
1        0  SORT  (AGGREGATE)
2        1    INDEX (FAST FULL SCAN) OF ‘pk_emp’ (UNIQUE) (cost=2)

4. Performance Test Results

Testing with 50,000 records produced the following results:

SELECT COUNT(idx) FROM TESTBBS;
-- Execution time: 225ms

SELECT /*+ INDEX_FFS(TESTBBS TESTBBS_IDX) */ COUNT(idx) FROM TESTBBS;
-- Execution time: 17ms

We can see that using Index Fast Full Scan improves performance by over 10 times.

5. Conclusion

If you want to speed up COUNT() in Oracle, make active use of Index Fast Full Scan. 

This method is particularly effective when working with large datasets and frequent COUNT() queries. 

The hint is simple to use, so give it a try and see the performance boost for yourself!

Why You Should Use Hashtags on Your Blog and Their Benefits

 When running a blog, you’ve probably wondered, “Do I really need hashtags?” I used to think they were just decorative, so I didn’t take them seriously. 

But once I started using hashtags properly, my visitor numbers increased noticeably. 

Today, I’ll share my personal experience and explain why using hashtags on your blog is essential and how they can benefit you.

1. Search Exposure Optimization (SEO Benefits)

Hashtags play a crucial role in boosting your blog’s search exposure. 

When users search for specific keywords, posts with related hashtags are more likely to appear at the top of search results. 

For example, if you add the hashtag ‘Cafe Recommendations,’ people looking for cafes will easily find your post. 

I’ve experienced a significant increase in visitors by optimizing my hashtags around popular keywords.

2. Connecting Related Content

Hashtags also help connect blog posts with similar topics. 

Posts using the same hashtag form a kind of category, making it easier for readers to explore related content on your blog. 

By using hashtags like ‘Travel Reviews’ and ‘Foodie Adventures,’ I’ve noticed a sharp increase in page views and the time readers spend on my blog.

3. Attracting Target Readers

Hashtags are a powerful tool for gathering readers who share specific interests. 

People who search for specific hashtags are already interested in those topics, so they’re more likely to engage with and respond to your content. 

I’ve seen more comments and likes on posts with hashtags like ‘Tech Reviews’ and ‘Blogging Tips.’

4. Strengthening Branding and Expertise

Consistent use of specific hashtags helps establish your blog’s identity. 

When you regularly use hashtags on a particular subject, readers start recognizing your blog as a go-to source for that field. 

I’ve built trust and credibility by using hashtags like ‘Tech,’ ‘Digital Nomad,’ and ‘Productivity Tools.’

5. Reflecting Trends and Boosting Visibility

Using trendy hashtags can help your posts gain visibility on hot topics. 

By including popular or seasonal hashtags, your content can quickly gain traction. 

Tags like ‘Cherry Blossom Spots’ or ‘Black Friday Sales’ can dramatically boost views, especially during relevant seasons.

Conclusion

Hashtags aren’t just decorative—they’re essential for your blog’s growth and exposure. 

From optimizing search visibility and attracting readers to strengthening your branding and expertise, the benefits of using hashtags are vast. 

Use them strategically to reach a broader audience and establish your blog’s unique identity.

I’d love to hear about your experiences with hashtags—please share your thoughts in the comments! :)

Best Value for Money! Anker Soundcore Space One Headset Review

 I’ve been a long-time fan of the Sennheiser brand, but my trust in Anker Soundcore has grown significantly after using their products recently. Through my experience with the Soundcore Liberty 2 and Liberty 4, I was able to personally appreciate their excellent features and quality. Based on that trust, my expectations were high when I purchased the new Anker Soundcore Space One headset — and it exceeded them.

Anker Soundcore Space One: A Perfect Balance of Price and Performance The Soundcore Space One headset offers incredible performance for its price. Its active noise canceling (ANC) feature is powerful, and the clear, well-balanced sound quality provides great satisfaction whether you’re listening to music or watching videos.

Product Specifications

• Driver Size: 40mm Dynamic Driver

• Noise Canceling: Hybrid ANC

• Battery Life: Up to 40 hours (ANC on) / Up to 55 hours (ANC off)

• Charging Method: USB-C Fast Charging

• Bluetooth Version: Bluetooth 5.3

• Supported Codecs: SBC, AAC, LDAC

• Multipoint Connection: Supported

• Weight: Approximately 260g

Price and Color Options This product comes in three colors: black, sky blue, and ivory. Interestingly, the sky blue model was almost half the price of the black one, making it a very attractive option price-wise. I eventually chose the sky blue model, but it did come with an unexpected drawback.

Drawback of the Sky Blue Model While the sky blue model’s color is beautiful, it gets dirty very easily. Fingerprints, dust, and stains are quick to appear and hard to clean. Although these marks aren’t visible when wearing the headset, they become quite noticeable when taking it on and off. If maintenance is a concern, the black model might be a better choice.

Conclusion The Anker Soundcore Space One headset is one of the best value-for-money products out there. It offers outstanding sound quality and powerful noise canceling at a reasonable price. If you’ve used Soundcore products before, you’ll already be familiar with the brand’s reliability and quality. That said, if you prefer a cleaner look with less maintenance, I’d recommend going for the black model.

If you’re searching for a high-quality, budget-friendly headset, the Anker Soundcore Space One is a solid choice!

CapCut's Strengths and Key Features Guide

 

1. Strengths of CapCut

CapCut is a free video editing tool with powerful features comparable to paid programs. Here are its main strengths:

• Free to Use: Most features are available for free, making it accessible for beginners or users who want simple video editing without financial burden.
• Intuitive UI: It offers a clean and user-friendly interface, allowing even those with no video editing experience to use it easily.
• Abundant Effects and Templates: CapCut provides trendy filters, transitions, stickers, and text animations, enabling the creation of high-quality videos in a short time.
• Automatic Subtitle Generation: Its AI-based automatic subtitle feature quickly inserts and edits subtitles to match the video’s audio.
• Support for Both Mobile and PC: Projects edited on mobile can seamlessly continue on PC, offering a flexible editing environment.

2. Weaknesses of CapCut

Even the best tools come with some limitations.

• Lack of Advanced Features: Compared to professional editing software like DaVinci Resolve and Adobe Premiere Pro, CapCut offers limited advanced color grading, audio editing, and multi-layer editing capabilities.
• 4K High-Quality Editing Limitations: When editing high-resolution videos, rendering speed can slow down, and there may be occasional quality degradation.
• Cloud Sync Restrictions: Synchronization between devices can sometimes be inconsistent when continuing a project on another device.

3. How to Use CapCut’s Key Features

Here’s a step-by-step guide to maximizing CapCut’s powerful features.

3.1 Editing Video Clips

1. Create a Project: Launch CapCut and select 'New Project'.
2. Add Media: Click the 'Add Media' button to import the video for editing.
3. Trim and Split Clips: Select the clip on the timeline and use the 'Split' function to keep only the desired parts or delete sections.

3.2 Applying Effects and Filters

1. Add Effects: Choose a video effect from the 'Effects' tab and drag it onto the clip.
2. Apply Filters: Go to the 'Filters' tab, select a color correction filter, and adjust its intensity.

3.3 Adding Subtitles and Text

1. Insert Text: Choose a style from the 'Text' tab and position the text on the screen.
2. Generate Automatic Subtitles: Use the 'Auto Captions' feature to convert speech to text and edit as needed.

3.4 Editing Audio and Music

1. Add Music: Select a track from CapCut’s built-in music library or upload your own.
2. Record Voiceover: Use the 'Add Voice' function to insert narration directly.

3.5 Transitions and Animation

1. Apply Scene Transitions: Add transitions between clips for smooth visual flow.
2. Text Animation: Enhance video quality with various text entrance, emphasis, and exit animations.

4. Personal Opinion

Thanks to its intuitive interface and powerful core features, CapCut is especially optimized for creating short-form content like YouTube Shorts, TikTok, and Reels. 

Despite being free, it offers automatic subtitles, diverse templates, and filters, making it highly satisfying for both beginners and intermediate users. 

However, for long-term and advanced video production, switching to professional software should be considered.

CapCut is a highly recommended tool for creators who want to produce trendy videos quickly.

Why Use Notion: Pros, Cons, and Best Practices

 

1. Why Use Notion?

Notion is more than just a note-taking app — it’s a powerful all-in-one workspace. 

From notes and task management to project tracking and databases, Notion helps you manage everything in one place. Its intuitive interface and highly customizable features make it popular among individuals and teams alike.

2. Pros of Notion

(1) All-in-One Workspace

• Combines notes, document creation, project management, and databases in a single app.

• Offers multiple views (list, gallery, board, calendar) for visualizing data.

(2) Powerful Customization

• Flexible page layouts that you can design freely.

• Use of templates, icons, emojis, and color schemes enhances visual appeal.

(3) Collaboration Features

• Real-time sync with comments and mentions for efficient communication.

• Access management through page-specific permissions.

(4) Extensive Integrations

• Connects with Google Drive, Figma, GitHub, and more.

• Embeds external content directly into Notion pages.

3. Cons of Notion

(1) Steep Learning Curve

• Its wide range of features can take time to master.

• Efficient use requires familiarity with templates and shortcuts.

(2) Limited Offline Access

• Requires an internet connection for editing pages.

• Offline access is read-only and limited.

(3) Speed Issues

• Large amounts of data can lead to slower loading times.

• Mobile app performance lags behind the desktop version.

4. How to Use Notion Effectively

(1) Leverage Templates

• Quickly set up pages using free or paid templates.

• Customize templates for personal schedules, project management, and book tracking.

(2) Utilize Databases

• Organize data efficiently with tags, filters, and sorting.

• Visualize data using different views like table, board, and calendar.

(3) Create a Wiki-Style Knowledge Base

• Manage company knowledge systematically.

• Document manuals, meeting notes, and work processes.

(4) Master Shortcuts and Commands

• Use the / command for quick block insertion and page creation.

• Mention pages and set dates conveniently with the @ command.

5. Personal Thoughts

What I love most about Notion is its flexibility and visual organization. When managing projects, I can seamlessly switch between Trello-style board views and calendar views as needed. However, the occasional slowdown and limited offline functionality can be frustrating. Despite these drawbacks, Notion’s ability to consolidate various tasks into a single platform makes it an essential tool in both my work and personal life.

6. Conclusion

Notion is a powerful tool that, when used effectively, can boost both productivity and creativity. Once you overcome the initial learning curve, you can build a personalized, efficient workspace tailored to your needs. By setting up the right templates and database structures, you can transform Notion into your ultimate digital assistant!

Why I Chose the Bestisan SR06 Over the Edifier MR4

 

When buying audio equipment, the biggest concern is always performance for the price.

Recently, I was searching for speakers for my Desk-Fi setup and was torn between the Edifier MR4 and the Bestisan SR06. After reviewing numerous comparisons and testing them myself, I ultimately decided on the Bestisan SR06.

In this post, I'll break down why I made this choice by comparing both products.

🔍 Comparison: Edifier MR4 vs. Bestisan SR06

Feature	Edifier MR4	Bestisan SR06
Bluetooth Support	❌ Wired only	✅ Bluetooth 5.0
Optical Input	❌ None	✅ Supported
Remote Control	❌ None	✅ Included
Usage Purpose (PC-Fi / Desk-Fi)	✅ Optimized for PC-Fi	✅ Suitable for PC-Fi & multi-purpose use
Size	Relatively large	More compact
Output Power	21W x 2	50W x 2
Additional Features	Low/High adjustment	Bass/Treble control & EQ modes

🎧 Key Decision Factors

1️⃣ Bluetooth Support

Since the MR4 is designed as a studio monitor speaker, it does not support Bluetooth. However, I wanted to connect my speakers not just to my PC but also to my smartphone and tablet. In this regard, the Bestisan SR06 was the clear winner.

2️⃣ Optical Input Support

An optical input is useful when connecting to TVs or high-quality audio devices. The MR4 lacks this feature, whereas the SR06 offers it, making it a more versatile option.

3️⃣ Remote Control Availability

When using speakers on a desk, manually adjusting the settings can be inconvenient. Having a remote control is especially useful for volume control or switching inputs. The MR4 does not include a remote, but the SR06 does, adding to its convenience.

4️⃣ Suitability for Desk-Fi Use

The MR4 leans more towards being a monitor speaker, making it better suited for PC-Fi rather than a Desk-Fi setup. In contrast, the SR06 is adaptable for PC-Fi, TV, consoles, and even smartphones.

5️⃣ Size and Space Efficiency

The MR4 is similar in size to typical bookshelf speakers, taking up considerable desk space. The SR06, being more compact, allows for better space efficiency.

💡 Conclusion: Why Did I Choose the Bestisan SR06?

To be fair, the MR4 offers slightly clearer audio quality. However, considering my needs, convenience and expandability were more important factors.

• Bluetooth support → Wireless connectivity

• Optical input support → Connects to various devices

• Remote control included → Easier operation

• Smaller size → Saves desk space

If the MR4 is optimized for wired setups prioritizing sound quality, the Bestisan SR06 is a more versatile speaker for multiple uses.

In the end, I chose the Bestisan SR06 because I wanted a speaker that could be used for more than just PC-Fi purposes.

✔️ If you need high-quality audio in a fixed setup, go for the MR4. 

✔️ If you prioritize convenience and multi-purpose use, the Bestisan SR06 is the better choice.

Choose based on your needs, and you won’t regret your decision! 😊

The Ultimate Guide to Splitting Text in Excel

 

Excel is a powerful tool for managing and organizing data, and one of its most useful features is the ability to split text into multiple columns. 

Whether you're working with CSV files, separating names, or parsing data from different sources, knowing how to efficiently split text can save time and improve accuracy.

Methods for Splitting Text in Excel

There are several ways to split text in Excel, depending on the complexity of the data and the level of automation you require.

1. Using "Text to Columns" Feature

The "Text to Columns" feature is a built-in tool in Excel that allows users to split text based on delimiters such as commas, spaces, or custom characters.

Steps to Use Text to Columns:

1. Select the column containing the text you want to split.
2. Go to Data > Text to Columns.
3. Choose Delimited if your text is separated by a specific character, or Fixed Width if the text has uniform spacing.
4. Select the delimiter (e.g., comma, space, tab, or custom delimiter).
5. Click Finish, and Excel will split the text into separate columns.

2. Using Excel Formulas

For dynamic text splitting that updates automatically, you can use formulas such as LEFT, RIGHT, MID, SEARCH, and TEXTSPLIT (Excel 365).

Commonly Used Formulas:

Formula	Purpose	Example	Result
LEFT(A2, SEARCH(" ", A2)-1)	Extracts the first word before a space	"John Doe"	"John"
RIGHT(A2, LEN(A2) - SEARCH(" ", A2))	Extracts the last word after a space	"John Doe"	"Doe"
TEXTSPLIT(A2, " ")	Splits text by space (Excel 365)	"Apple Orange"	{"Apple", "Orange"}

3. Using Power Query

Power Query is a powerful tool for handling large datasets and allows for advanced text manipulation.

Steps to Split Text Using Power Query:

1. Select your dataset and go to Data > Get & Transform > From Table/Range.
2. In Power Query Editor, select the column and choose Split Column > By Delimiter.
3. Choose the delimiter and select OK.
4. Click Close & Load to return the split data to Excel.

4. Using VBA for Automation

For repetitive tasks, you can automate text splitting using VBA. Here's a simple VBA script:

vba

Sub SplitText()
    Dim cell As Range
    Dim arr As Variant
    Dim i As Integer
    Dim targetColumn As Integer

    targetColumn = 2 ' Column to place the split data
    For Each cell In Selection
        arr = Split(cell.Value, " ") ' Change delimiter as needed
        For i = LBound(arr) To UBound(arr)
            cell.Offset(0, i + targetColumn - 1).Value = arr(i)
        Next i
    Next cell
End Sub

Conclusion

Whether you're working with simple data or handling complex datasets, Excel provides multiple ways to split text efficiently. 

Depending on your needs, you can use Text to Columns for quick splits, formulas for dynamic updates, Power Query for advanced transformations, or VBA for automation. Mastering these techniques will enhance your data management skills and improve your productivity.

Choosing Between Node.js and Bun for Backend Development in 2025

 Here's the English version of your blog post:

---

As of 2025, Node.js and Bun are two prominent JavaScript runtimes with distinct advantages. Node.js has been widely used for years due to its stability and rich ecosystem, while Bun is emerging as a compelling alternative with impressive performance and built-in features.

Performance Comparison

Bun is built on WebKit’s JavaScriptCore engine, offering significantly faster execution speeds. In particular, it outperforms Node.js in server initialization and file system access. For example, when running a simple HTTP server, Bun initializes up to three times faster than Node.js. Additionally, package installation with bun install is up to 30 times faster than npm or yarn, improving development efficiency.

Built-in Features and Compatibility

Bun includes a runtime, package manager, bundler, transpiler, and test runner, providing an all-in-one development environment without the need for additional tools. It also natively supports TypeScript, allowing developers to execute TypeScript code without extra configurations. Moreover, Bun maintains compatibility with Node.js APIs, making migration from Node.js relatively seamless.

Real-World Use Cases

Due to its speed and integrated development environment, Bun is increasingly adopted in startups and small-scale projects, where rapid prototyping and deployment are crucial. On the other hand, large enterprises and mission-critical systems still favor Node.js for its stability and well-established ecosystem.

Personal Opinion

Personally, I find Bun’s innovative approach and performance improvements quite impressive. Its unified development experience enhances productivity, while fast package installation and server initialization make it highly efficient. However, since its ecosystem and community support are not yet as mature as Node.js, choosing the right runtime should depend on the project’s scale and requirements.

Conclusion

Node.js and Bun each have their own strengths. If you prioritize stability and a well-supported ecosystem, Node.js remains a solid choice. However, if you seek high performance and an all-in-one development environment, Bun is worth considering. The key to successful development lies in carefully evaluating your project’s needs and selecting the most suitable tool.

How to Speed Up Windows 11 on Low-Spec PCs

 Windows 11, with its sleek design and advanced features, can sometimes be a bit too demanding for low-spec PCs. However, there are several ways to boost performance and make the operating system run more smoothly, even on older or less powerful hardware. In this guide, we will walk through some effective tips to help speed up Windows 11 on your low-spec PC.

1. Turn Off Unnecessary Visual Effects

Windows 11 has many visual effects that enhance the user experience but can slow down older systems. Disabling these effects can free up system resources and speed up your PC.

• How to do it:
  1. Press Win + R to open the Run dialog.
  2. Type sysdm.cpl and press Enter.
  3. In the System Properties window, go to the Advanced tab.
  4. Click Settings under Performance.
  5. Choose Adjust for best performance to turn off all animations, or manually select which visual effects to disable.

2. Disable Startup Programs

Many programs set themselves to launch automatically when Windows starts. These background processes can consume system resources and slow down your PC’s boot time.

• How to do it:
  1. Right-click the taskbar and select Task Manager.
  2. Go to the Startup tab.
  3. Right-click and disable unnecessary programs that don’t need to start automatically with Windows.

3. Use Storage Sense for Automatic Cleanup

Windows 11 includes a feature called Storage Sense that automatically cleans up temporary files, old system files, and other unneeded data, freeing up disk space and improving performance.

• How to do it:
  1. Go to Settings > System > Storage.
  2. Turn on Storage Sense and set it to run automatically to delete temporary files and optimize storage.

4. Adjust Power Settings

By default, Windows 11 is set to power-saving mode, which can limit system performance. Switching to a higher power plan can help maximize your PC’s performance.

• How to do it:
  1. Go to Settings > System > Power & battery.
  2. Under Power mode, select Best performance.

5. Uninstall Unnecessary Software

Unnecessary software and bloatware can take up valuable system resources. Uninstalling unwanted applications can help free up storage and improve your PC’s speed.

• How to do it:
  1. Go to Settings > Apps > Installed apps.
  2. Review the list and uninstall any apps you don’t need.

6. Use Lightweight Alternatives to Heavy Programs

Some applications can be resource-heavy and slow down your system. For example, instead of using Microsoft Office, you could opt for lightweight alternatives like LibreOffice. Similarly, using Google Chrome instead of more resource-demanding browsers like Microsoft Edge can improve performance.

7. Update Drivers and Windows

Outdated drivers can cause performance issues. Keeping your drivers and Windows updated ensures that your PC is running efficiently with the latest bug fixes and performance improvements.

• How to do it:
  1. Go to Settings > Windows Update and click Check for updates.
  2. Update all drivers using Device Manager by right-clicking your hardware and selecting Update driver.

8. Add More RAM (If Possible)

Although this might not be an immediate software tweak, if your low-spec PC allows it, adding more RAM can significantly boost performance, especially if you tend to run multiple applications at once.

9. Switch to a Lighter Theme

Windows 11 comes with a default dark theme, which looks great but can be resource-intensive. Switching to a lighter, simpler theme can reduce some of the strain on your system.

• How to do it:
  1. Go to Settings > Personalization > Themes.
  2. Select a simpler theme with fewer animations and effects.

10. Consider a Fresh Windows Install

If your PC is sluggish despite all efforts, a fresh install of Windows 11 may give your system a new start, removing any old files, settings, or system issues causing slowdowns. Be sure to back up your data before reinstalling the operating system.

Conclusion

Even with a low-spec PC, you can significantly improve the performance of Windows 11 by adjusting settings, cleaning up unnecessary files, and optimizing the system. By following these simple tips, you’ll be able to enjoy a smoother and faster experience without the need for expensive hardware upgrades.

Start applying these tips today and experience a noticeable difference in your PC’s performance!

Complete Guide to the Excel SUMIF Function: Adding Values Based on a Condition

In this blog post, we'll explore the powerful SUMIF function in Excel, which allows you to sum values in a range that meet a specific condition or criteria. Whether you're managing financial data, tracking sales, or analyzing any other type of dataset, SUMIF is an invaluable tool for filtering data and calculating sums based on specified conditions.

What is the SUMIF Function?

The SUMIF function is designed to add up values in a range that satisfy a given condition. The general syntax of the function is:

=SUMIF(range, criteria, [sum_range])

• range: The range of cells that you want to apply the condition to.
• criteria: The condition or criteria that define which cells will be summed.
• sum_range (optional): The range of cells to sum. If this is omitted, Excel will sum the values in the range.

How to Use the SUMIF Function

Let’s look at some examples to understand how SUMIF works. We'll present the examples in table format to help visualize the data.

Example 1: Summing Values Based on a Numeric Condition

Sales Amount	Sales Figure
200	150
600	400
800	350
300	500

You want to sum all sales figures greater than $500. The formula would be:

=SUMIF(A2:A5, ">500", B2:B5)

In this case, the formula sums all sales figures in B2:B5 where the corresponding value in A2:A5 is greater than 500.

Example 2: Summing Values Based on a Text Condition

Salesperson	Sales Figure
John	300
Alice	200
John	500
John	700

You want to sum all sales made by "John." The formula would be:

=SUMIF(A2:A5, "John", B2:B5)

This formula sums all values in B2:B5 where the corresponding value in A2:A5 is "John."

Example 3: Using Wildcards with SUMIF

Product Name	Sales Figure
Book ABC	100
Book XYZ	200
Pen ABC	150
Book DEF	300

You want to sum all sales for products starting with "Book." The formula would be:

=SUMIF(A2:A5, "Book*", B2:B5)

This formula sums all sales figures in B2:B5 where the corresponding value in A2:A5 starts with "Book."

Common Use Cases for SUMIF

The SUMIF function can be used in a variety of scenarios:

• Financial Analysis: Adding up sales above a certain threshold, summing expenses for specific categories, etc.
• Project Management: Summing hours worked by a specific employee or team, tracking progress based on task completion status.
• Sales Tracking: Calculating the total sales for particular products, regions, or sales representatives.

Conclusion

The SUMIF function is one of the most useful and straightforward functions in Excel for adding up data based on specific conditions. By mastering SUMIF, you can streamline your data analysis tasks and make your spreadsheet calculations more efficient. If you need more complex calculations, you can also explore the SUMIFS function, which allows you to apply multiple criteria.

Start applying SUMIF to your Excel sheets today and see how it can simplify your work!

MySQL Performance Tuning with Hints: Usage and Practical Examples

 

MySQL performance tuning is a crucial task that determines the efficiency and speed of your database. Especially with complex queries, using hints properly can optimize the execution plan and significantly enhance performance. In this post, we’ll explore the concept of MySQL hints, frequently used hints with practical examples, and some personal tips from real-world experience.

1. What Are MySQL Hints?

Hints are directives that provide guidance to the MySQL optimizer on how to execute a query. Although the optimizer usually creates efficient execution plans, there are cases where it chooses suboptimal paths. In such scenarios, hints can be used to enforce a more efficient execution method.

2. Commonly Used MySQL Hints

2.1 USE INDEX

Forces MySQL to use a specific index.

SELECT * FROM g5_board_new USE INDEX(idx_regDt)
WHERE regDt BETWEEN '2025-01-01' AND '2025-01-31';

Personal Opinion: Sometimes MySQL fails to choose the right index. Using USE INDEX can greatly improve query speed when this happens.

2.2 FORCE INDEX

Forces MySQL to use the specified index, even if it seems suboptimal.

SELECT * FROM g5_board_new FORCE INDEX(idx_regDt)
WHERE regDt = '2025-01-01';

TIP: Unlike USE INDEX, FORCE INDEX more aggressively enforces the use of the specified index. Use it with caution.

2.3 IGNORE INDEX

Ignores a specific index and enforces a full table scan.

SELECT * FROM g5_board_new IGNORE INDEX(idx_regDt)
WHERE boardId = 'notice';

Personal Opinion: Sometimes avoiding a poorly chosen index and opting for a full table scan can actually improve performance.

2.4 STRAIGHT_JOIN

Forces the join order as written in the query.

SELECT *
FROM g5_board_new AS b STRAIGHT_JOIN g5_board AS g
ON b.boardId = g.boardId
WHERE g.status = 'active';

Personal Opinion: When the optimizer chooses an inefficient join order, using STRAIGHT_JOIN allows you to take control of the sequence.

2.5 SQL_CALC_FOUND_ROWS

Retrieves the total number of rows without the LIMIT restriction.

SELECT SQL_CALC_FOUND_ROWS *
FROM g5_board_new
WHERE regDt BETWEEN '2025-01-01' AND '2025-01-31'
LIMIT 10;

SELECT FOUND_ROWS();

Personal Opinion: This is useful for pagination, but be cautious—retrieving the total row count for large datasets can impact performance.

3. Things to Keep in Mind When Using Hints

• Avoid Overusing Hints: The optimizer is usually efficient. Hints should only be used in specific situations.
• Check Execution Plans: Always use the EXPLAIN statement to verify how hints affect the query’s execution plan.

EXPLAIN SELECT * FROM g5_board_new USE INDEX(idx_regDt)
WHERE regDt = '2025-01-01';

4. Final Thoughts and Personal Tips

MySQL hints are powerful tools, but excessive use can degrade performance. In practice, it’s essential to review execution plans and thoroughly test hints to ensure they provide real benefits. From my own experience, I’ve seen cases where overusing hints led to slower performance. Use them wisely and strategically!

If you have MySQL tuning experiences or questions, feel free to share them in the comments!