Foreign key error

[manin]

Hello,

I am a newbie in databases and programming in general...

I build a new database, I have made 5 tables so far and have added foreign keys without problems
I have a table that must have foreign key from the same column of the same table 8 times...
I have changed the foreign key name but I get an error, that is not true....

Type is INT in both columns

Thanks!!!

 

[manin]

Never mind! I found it

I am sorry...

 

[VBService]

Type is INT in both columns

In SQL, the difference between INT and UNSIGNED INT can lead to issues when joining tables using foreign keys.

• INT: Can store integer values in the range of -2,147,483,648 to 2,147,483,647.
• UNSIGNED INT: Stores values in the range of 0 to 4,294,967,295 (positive numbers only).

If you attempt to join an id field of type INT in one table with UNSIGNED INT in another, SQL may raise an error or warning because the ranges of these two data types do not overlap.

CREATE TABLE Table1 (
    id UNSIGNED INT PRIMARY KEY
);

CREATE TABLE Table2 (
    id INT PRIMARY KEY
    table1_id UNSIGNED INT,
    FOREIGN KEY (table1_id) REFERENCES Table1(id)
);