How to Configure MySQL Auto-Increment to Start at 0001?

Setting Auto-Increment Format to 0001 in MySQL

Question: How can MySQL be configured to auto-increment a primary key in a four-digit format (e.g., 0001 instead of 1)?

Answer:

To achieve a four-digit auto-increment format in MySQL, follow these steps:

1. Create a Table with an AUTO_INCREMENT Column:

   <code class="sql">CREATE TABLE my_table (
       id INT NOT NULL AUTO_INCREMENT,
       PRIMARY KEY (id)
   ) ENGINE=InnoDB;</code>

2. Modify the Column to Use ZEROFILL Attribute:

   By default, MySQL auto-increments values without padding. To enable zero-padding, add the ZEROFILL attribute to the column definition:

   <code class="sql">ALTER TABLE my_table MODIFY COLUMN id INT NOT NULL AUTO_INCREMENT ZEROFILL;</code>

3. Restart MySQL Server or Issue FLUSH:

   To apply the changes, you need to either restart the MySQL server or issue a FLUSH TABLES command:

   <code class="sql">FLUSH TABLES;</code>

After following these steps, the id column in the my_table will auto-increment in the 0001 format.

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