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How to set varchar primary key field in Mysql

How to set varchar primary key field in Mysql

Table structure of Users table

 CREATE TABLE `users` (
   `id` varchar(36) NOT NULL DEFAULT 'InitiallyEmpty',
   `first_name` varchar(100) NOT NULL,
   `last_name` varchar(100) NULL,
   `email` varchar(100) NOT NULL,
   `password` varchar(100) NOT NULL,
   PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8

Want to fill id an automatically filled. You need to create trigger


Trigger structure for automatically update

DROP trigger if exists before_insert_users;
delimiter $$
CREATE TRIGGER before_insert_users
BEFORE INSERT ON users
FOR EACH ROW
BEGIN
    SET new.id = uuid();
END $$

 delimiter ;

Now create insert query

insert into users (first_name,last_name,email,password) values ('Sudhir','Pandey','psudhir20@gmail.com','123465');
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Comments

  1. Sankar19 October 2026 at 10:34

    This article provides a practical example of using a VARCHAR field as a primary key in MySQL and automatically generating UUIDs with a BEFORE INSERT trigger. This approach can be useful when applications require unique identifiers instead of traditional auto-incrementing integer IDs. Understanding database design and key generation is important when building reliable, scalable applications.

    Developers working with Python applications can benefit from learning how to map database tables to Python models and manage database operations efficiently. The SQLAlchemy Course is relevant for understanding ORM concepts and integrating Python applications with relational databases.

    ReplyDelete
  2. Sankar19 October 2026 at 10:34

    Beyond individual database operations, understanding data modeling, data pipelines, and database integration is valuable for building robust data-driven systems. The Data Engineering Course is another relevant learning resource for developers interested in strengthening their data engineering skills.

    ReplyDelete

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