Error Code: 1062. Duplicate entry '1' for key 'PRIMARY'

Question 1

The ~~main~~ reason why the error has been generated is because there is already an existing value of 1 for the column ID in which you define it as PRIMARY KEY (values are unique) in the table you are inserting.

Why not set the column ID as AUTO_INCREMENT?

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

and when you are inserting record, you can now skip the column ID

INSERT INTO `PROGETTO`.`UFFICIO-INFORMAZIONI` (`viale`, `num_civico`, ...) 
VALUES ('Viale Cogel ', '120', ...)

Question 2

If you are using PHPMyAdmin You can be solved this issue by doing this:

CAUTION: Don't use this solution if you want to maintain existing records in your table.

Step 1: Select database export method to custom:

enter image description here

Step 2: Please make sure to check truncate table before insert in data creation options:

enter image description here

Now you are able to import this database successfully.

Question 3

If you have a new database and you make a fresh clean import, the problem may come from inserting data that contains a '0' incrementation and this would transform to '1' with AUTO_INCREMENT and cause this error.

My solution was to use in the sql import file.

SET SESSION sql_mode='NO_AUTO_VALUE_ON_ZERO';

Question 4

If you are trying to populate a table from a SQL dump, make sure that the table listed in the "INSERT INTO" statements of the dump is the same one you are trying to populate. Opening "MyTable" and importing with a SQL dump will throw exactly that kind of error if the dump is trying to put entries into "MyOtherTable", which may already have entries.

Question 5

The problem is related with your file - you are trying to create a DB using a copy - at the top of your file you will find something like this:

CREATE DATABASE IF NOT EXISTS *THE_NAME_OF_YOUR_DB* DEFAULT CHARACTER SET latin1 COLLATE latin1_general_ci; USE *THE_NAME_OF_YOUR_DB*;

and I'm sure that you already have a DB with this name - IN THE SAME SERVER - please check. Just change the name OR ERASE THIS LINE!

Question 6

When I get this kind of error I had to update the data type by a notch. For Example, if I have it as "tiny int" change it to "small int" ~ Nita

Question 7

Also check your triggers.

Encountered this with a history table trigger which tried to insert the main table id into the history table id instead of the correct hist-table.source_id column.

The update statement did not touch the id column at all so took some time to find:

UPDATE source_table SET status = 0;

The trigger tried to do something similar to this:

FOR EACH ROW
BEGIN
    INSERT INTO `history_table` (`action`,`id`,`status`,`time_created`)
    VALUES('update', NEW.id, NEW.status, NEW.time_created);
END;

Was corrected to something like this:

FOR EACH ROW
BEGIN
    INSERT INTO `history_table` (`action`,`source_id`,`status`,`time_created`)
    VALUES('update', NEW.id, NEW.status, NEW.time_created);
END;

Question 8

I just encountered the same issue but here it seemed to come from the fact that I declared the ID-column to be UNsigned and that in combination with an ID-value of '0' (zero) caused the import to fail...

So by changing the value of every ID (PK-column) that I'd declared '0' and every corresponding FK to the new value, my issue was solved.