When should I use UNSIGNED and SIGNED INT in MySQL?

Question

When should I use UNSIGNED and SIGNED INT in MySQL? What is better to use or this is just personal prefernce? Because I've seen it used like this;

id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT

and

id INT(11) NOT NULL AUTO_INCREMENT

Answer 1

When should I use UNSIGNED and SIGNED INT in MySQL ? What is better to use or this is just personal prefernce ? Because I've seen it used like this;

id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT

and

id INT(11) NOT NULL AUTO_INCREMENT

Answer 2

When should I use UNSIGNED and SIGNED INT in MySQL ? What is better to use or this is just personal prefernce ? Because I've seen it used like this;

id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT

and

id INT(11) NOT NULL AUTO_INCREMENT

Answer 3

When should I use UNSIGNED and SIGNED INT in MySQL ? What is better to use or this is just personal prefernce ? Because I've seen it used like this;

id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT

and

id INT(11) NOT NULL AUTO_INCREMENT

Answer 4

When should I use UNSIGNED and SIGNED INT in MySQL ? What is better to use or this is just personal prefernce ? Because I've seen it used like this;

id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT

and

id INT(11) NOT NULL AUTO_INCREMENT

Answer 5

When should I use UNSIGNED and SIGNED INT in MySQL ? What is better to use or this is just personal prefernce ? Because I've seen it used like this;

id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT

and

id INT(11) NOT NULL AUTO_INCREMENT

Answer 6

When should I use UNSIGNED and SIGNED INT in MySQL ? What is better to use or this is just personal prefernce ? Because I've seen it used like this;

id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT

and

id INT(11) NOT NULL AUTO_INCREMENT

Answer 7

When should I use UNSIGNED and SIGNED INT in MySQL ? What is better to use or this is just personal prefernce ? Because I've seen it used like this;

id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT

and

id INT(11) NOT NULL AUTO_INCREMENT

Answer 8

When should I use UNSIGNED and SIGNED INT in MySQL ? What is better to use or this is just personal prefernce ? Because I've seen it used like this;

id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT

and

id INT(11) NOT NULL AUTO_INCREMENT

Answer 9

If you wanna keep it simply, then you have to keep in mind if you want to calculate with these numbers as well (subtraction). If you for example calculate A - B and B is bigger than A, you can get in trouble. There you would have to CAST the SIGNED number to a UNSIGNED.

You can read more about this for example here: BIGINT UNSIGNED VALUE IS out of range My SQL

Answer 10

Use the unsigned if u not need use foreign this field on current table. I was have next problem:

General error: 3780 Referencing column 'event_id' and referenced column 'id' in foreign key constraint 'events_event_id_foreign' are incompatible. (SQL: alter table `events` add constraint `events_event_id_foreign` foreign key (`event_id`) references `users` (`id`) on delete cascade)