session user_id

[mankolele]

Hi all.

I have been reading notes on how to use sessions and cookies,I see that there is a user_id which is used to identify each user but dont see how it is generated and assigned to a particular user.

Does anyone have a clear explanation on how its generated coz even on the insertstatement it is not there on the values??

[Motoma]

Hi all.

I have been reading notes on how to use sessions and cookies,I see that there is a user_id which is used to identify each user but dont see how it is generated and assigned to a particular user.

Does anyone have a clear explanation on how its generated coz even on the insertstatement it is not there on the values??

User IDs are usually generated by the database when a user is created by having a NOT NULL AUTO_INCREMENT field in the table.
They are usually grabbed from a database when a user logs in.

[mankolele]

User IDs are usually generated by the database when a user is created by having a NOT NULL AUTO_INCREMENT field in the table.
They are usually grabbed from a database when a user logs in.

Thanks for responding.

that is exacly what I dont under stand the id I have been using is the aouto increment which starts from 1,2,3 goes on ,is it the same how do I link it to the username I just dont get the logic I guess.

[Motoma]

Thanks for responding.

that is exacly what I dont under stand the id I have been using is the aouto increment which starts from 1,2,3 goes on ,is it the same how do I link it to the username I just dont get the logic I guess.

When you insert an user into a user table with an autoincrement field, it will get assigned an ID (the next number in the sequence) . When you check to see if a user exists, you will grab the id as well as the user information:

SELECT user_id FROM userTable WHERE username='mankolele' and password='toasty';
 

Hope this helps.

[Atli]

$_Session['user_id'] is not something that exists by default. It has no connection to any database or anything else.
It is simply a variable, like $user_id, except it is stored in the _Session array.
It doesnt have to be user_id, it could be i_am_bob and the php script wouldnt give a frick.
If you want to use it, you have to create it and give it a value, just like any variable.

User id's are passed in the _Session array pretty frequently and most coders try to use variable names that clearly identify what they represent, so it is not uncommon to see user id's stored as user_id or UserID or something simular.