What is SQL ENUM

Implementing ENUM in Real Scenarios

Let's explore some practical examples of ENUM.

Example 1: Basic Usage

Suppose you're designing a table for a survey system where a user can only rate their experience as 'Poor', 'Average', or 'Excellent'. You can use the ENUM type like so:

CREATE TABLE Survey (
  ID INT,
  UserExperience ENUM('Poor', 'Average', 'Excellent')
);

Example 2: Inserting and Querying Data

To insert data into the 'Survey' table:

INSERT INTO Survey(ID, UserExperience) VALUES(1, 'Average');

If you attempt to insert a value that isn't defined in the ENUM list, SQL will return an error.

To query data from the 'Survey' table:

SELECT * FROM Survey WHERE UserExperience = 'Average';

This will return all rows where the user's experience was 'Average'.

Frequently Asked Questions

Can I modify the list of values in an ENUM column after the table is created?

Yes, you can alter an ENUM list using the ALTER TABLE command, but you should be careful not to lose any data.

Is the order of the values in an ENUM list important?

Yes, ENUM assigns each value a number based on its position in the list, starting with 1.

Can I use numeric values in an ENUM list?

Yes, but they are treated as strings, not numbers.

Conclusion

The ENUM data type in SQL is a valuable tool when you need to ensure data consistency in a column. It's especially useful when dealing with columns that have a known, limited set of values. Understanding and effectively using ENUM will help improve your database's reliability and your efficiency as a developer. It's just another tool in the SQL toolkit that, when used correctly, makes database management a smoother and more streamlined process.

If you want to learn about SQL, you can read the below-mentioned articles:

• LIMIT in SQL
• Create Table in SQL
• Basic SQL
• Data Types in SQL
• Operators in SQL
• SQL Expressions

We hope this article helped you in understanding database management system and the types of DBMS. You can read more such articles on our platform, Coding Ninjas Studio. You will find articles on almost every topic on our platform. Also, you can practice coding questions at Coding Ninjas to crack good product-based companies.