How do I resolve the \'Duplicate Entry for Primary Key\' error when inserting data into the UFFICIO-INFORMAZIONI table?

Error: Duplicate Entry for Primary Key

When attempting to insert data into the UFFICIO-INFORMAZIONI table, an error occurs due to a duplicate entry for the ID column, which is defined as the primary key.

Understanding the Primary Key

A primary key is a unique identifier for each row in a table, ensuring that there are no duplicate entries. In this case, the ID column is set as the primary key, indicating that each row must have a unique ID value.

Inspecting the Table Structure

The provided table definition shows that the ID column is an integer (INT(11)) with a NOT NULL constraint, meaning that it cannot be left empty. It also has a PRIMARY KEY constraint, which enforces the uniqueness of the values in this column.

Resolving the Error

The error message indicates that an entry with the ID value of 1 already exists in the table. To resolve this issue, ensure that the data being inserted does not contain duplicate values for the ID column.

Using Auto-Increment

An alternative solution is to define the ID column as AUTO_INCREMENT. This allows the database to automatically generate unique values for the ID column, ensuring that no duplicate entries are created.

To set the ID column as AUTO_INCREMENT, modify the table definition as follows:

CREATE  TABLE IF NOT EXISTS `PROGETTO`.`UFFICIO-INFORMAZIONI` (
  `ID` INT(11) NOT NULL AUTO_INCREMENT,
  `viale` VARCHAR(45) NULL ,
  ...
)

With this modification, the ID column will automatically increment for each new row inserted, eliminating the need to specify it explicitly when inserting data.

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