EyeSoothe was ranked #32 in China in the “Health & Fitness” category! ✨

🎉 EyeSoothe was ranked #32 in China in the “Health & Fitness” category! 👀✨
Eye fatigue, vision changes, color blindness detection, virtual glasses trying on … all these problems, EyeSoothe can help you solve! As an all-in-one eye health app, EyeSoothe integrates several powerful features designed to help you better protect your eyesight, relieve eye fatigue, and keep an eye on your eye health. 📱💡

https://apps.apple.com/app/eyesoothe/id6478070048

Why EyeSoothe?

  • AI Smart Glasses Trial: easily find the most suitable style of glasses for you through advanced AI technology.
  • Vision tracking: record your vision changes in real time to help you find problems early and take timely measures.
  • Color Blindness Detection: accurately detects red-green color blindness, helping you understand your sensitivity to color.
  • Eye Relaxation Exercise: Provide professional eye relaxation guidance to relieve fatigue after long hours of eye use.
  • Cross-platform support: Whether you are using iPhone, iPad or Mac, you can seamlessly use EyeSoothe to take care of your eyes anytime and anywhere.

Usage Scenarios:

  • Daily eye care: Easily track changes in vision and keep abreast of eye health trends.
  • Work environment health: effectively relieve eye fatigue caused by the screen, improve work efficiency.
  • Smart Glasses Shopping: Choose the most suitable style of glasses for yourself through virtual trying on, saving time and effort.
  • Eye health management for the whole family: Share with your family, check your eyesight regularly and protect the eye health of the whole family.

Your eyes deserve better care! 👁️❤️

Whether you need to protect your eyesight, shop for eyeglasses, or take a relaxing break for your eyes, EyeSoothe has the perfect solution. Download EyeSoothe now and let’s take care of your eye health and enjoy a clearer and more comfortable world together! 🌟

Download Address

https://apps.apple.com/app/eyesoothe/id6478070048

### Understanding the MySQL Error: Every Derived Table Must Have Its Own Alias The error `Every derived table must have its own alias` occurs in MySQL when a subquery or inline view is used in the `FROM` clause without assigning it an alias. This requirement ensures that each derived table (i.e., a table generated by a subquery) has a name, allowing references to its columns and improving query readability. #### Cause of the Error This error arises due to the absence of an alias for a subquery result set. For instance, consider the following query: ```sql SELECT * FROM (SELECT * FROM teachers_bkp WHERE country = 'USA') WHERE age = (SELECT MAX(age) FROM teachers_bkp); ``` In this case, the subquery `(SELECT * FROM teachers_bkp WHERE country = 'USA')` does not have an alias, which leads to the error [^1]. #### Resolving the Error To resolve the issue, assign an alias to the derived table using the `AS` keyword. The corrected version of the query would look like this: ```sql SELECT * FROM (SELECT * FROM teachers_bkp WHERE country = 'USA') AS usa_teachers WHERE age = (SELECT MAX(age) FROM teachers_bkp); ``` Here, `usa_teachers` serves as the alias for the derived table resulting from the subquery [^2]. #### Example Scenarios 1. **Using Subqueries in Complex Queries** When combining multiple tables or applying advanced functions like window functions, derived tables often appear. Consider the following example involving ranking: ```sql SELECT Department, Employee, Salary FROM ( SELECT D.name AS Department, E.name AS Employee, E.salary AS Salary, DENSE_RANK() OVER (PARTITION BY E.departmentId ORDER BY E.salary DESC) AS sm FROM Employee E JOIN Department D ON E.departmentId = D.id ) AS ranked_employees WHERE sm <= 3; ``` In this query, `ranked_employees` acts as the alias for the derived table created by the subquery [^2]. 2. **Counting Records from Derived Tables** Another common use case involves counting records from a derived table: ```sql SELECT COUNT(1) FROM ( SELECT MAX(id) FROM message WHERE STATUS != 2 AND from_id != 1 ) AS latest_messages; ``` Here, `latest_messages` provides the required alias for the derived table [^3]. #### Best Practices - Always assign meaningful aliases to derived tables for clarity. - Use the `AS` keyword explicitly for better readability, even though it's optional in MySQL. - Ensure nested subqueries are also aliased appropriately. By adhering to these guidelines, developers can avoid the `Every derived table must have its own alias` error and enhance the maintainability of their SQL code.
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