How Do I Make a MySQL Column AUTO_INCREMENT?

Transforming a MySQL Column into AUTO_INCREMENT

Modifying an existing MySQL column to become AUTO_INCREMENT is done using the ALTER TABLE command. The example SQL provided earlier has a syntax error. Here's the correct approach:

<code class="language-sql">ALTER TABLE document MODIFY COLUMN document_id INT AUTO_INCREMENT;</code>

Let's dissect this command:

• ALTER TABLE document: This targets the table named "document" for modification.
• MODIFY COLUMN document_id: This specifies the column, "document_id", to be changed.
• INT AUTO_INCREMENT: This sets the data type to integer (INT) and enables automatic incrementing for new rows.

After executing this statement, the document_id column will be an AUTO_INCREMENT column, typically also functioning as the primary key.

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