How to Configure Initial Values and Auto-Increment for a MySQL 'id' Column?

Initial Value Configuration and Auto-Incrementing in MySQL

When designing a MySQL database, it's often useful to initialize specific columns with predefined values and enable automatic increments for unique identifiers. The question at hand addresses these challenges regarding the "id" column in a MySQL table.

Setting Initial Value for "id" Column

To explicitly define an initial value for the "id" column, the ALTER TABLE command can be employed:

ALTER TABLE users AUTO_INCREMENT=1001;

This statement sets the auto-increment sequence for the "id" column to start from 1001.

Adding "id" Column with Initial Value

If the "id" column doesn't exist in the table, you can create it and specify an initial value simultaneously:

ALTER TABLE users ADD id INT UNSIGNED NOT NULL AUTO_INCREMENT,
ADD INDEX (id);

This statement creates an unsigned integer column named "id" that cannot be null and will automatically increment from 1001 onwards. Additionally, an index is added to enhance query performance when searching by the "id" column.

Insert Operation

With the "id" column properly configured, you can now execute an insert operation as usual, leaving the "id" column unspecified:

INSERT INTO users (name, email) VALUES ('{$name}', '{$email}');

The MySQL auto-increment mechanism will automatically assign the next available value (1001 and onwards) to the "id" column of the newly inserted row.

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