Mysql error: #1062 Duplicate entry for key 1

This problem occurs during the testing of the developed website background system:
Invalid Query: Duplicate entry '000000' for key 1
SQL is: INSERT INTO 'kq _ new' ('title', 'autor', 'type', 'content', 'isdel', 'adate', 'range ', 'lang ') values ('donation activities', 'yuanying', '3', ", '0', NOW (), '2', 'cn ')
Because it was the first time that we encountered such a problem. GOOGLE gave us a bit of similar issues, and there were many similar solutions, that is, the repair table (repair) and MySQL repair Tool myisamchk. After a try, the problem persists.

Finally, I realized that the type of the Self-incrementing field Id is wrong! Convert the data type!

Then I opened the MYSQL manual and found the description of TINYINT, SMALLINT, and INT types:

TINYINT [(M)] [UNSIGNED] [ZEROFILL]
A small integer. The signed range is-128 to 127, and the unsigned range is 0 to 255.

SMALLINT [(M)] [UNSIGNED] [ZEROFILL]
A small integer. The signed range is-32768 to 32767, And the unsigned range is 0 to 65535.

MEDIUMINT [(M)] [UNSIGNED] [ZEROFILL]
An integer of medium size. The signed range is-8388608 to 8388607, And the unsigned range is 0 to 16777215.

INT [(M)] [UNSIGNED] [ZEROFILL]
A normal integer. The signed range is-2147483648 to 2147483647, And the unsigned range is 0 to 4294967295.

INTEGER [(M)] [UNSIGNED] [ZEROFILL]
This is a synonym for INT.

BIGINT [(M)] [UNSIGNED] [ZEROFILL]
A large integer. The signed range is-9223372036854775808 to 9223372036854775807, And the unsigned range is 0
18446744073709551615.

So it turns out!
The reason for the error in other Invalid Query: Duplicate entry '000000' for key 1 on the internet is that