unique random number

aznur95

i try to create quiz script.

how i can generate 1800 (1-1800) different random numbers
and store them in db table called user.
no duplicate number.

then, i want to pick back that number
so that i can use one by one for select other record
from table called question that have id(1-1800) once the file activated by user
(meaning that once user send http get)
e.g:
1st - system will create 100 unique question from 1800 question and store to user table.
2nd - when user request for question system will give one question base on question id that have been store at user table before.
3rd - then..same like 2nd...until 100 question
4rd - i'm stuck......

my friend to me this should be work?
i don't know, just share it.
what is your opinion?

SELECT * FROM question ORDER BY RAND () LIMIT 100

plz, i'm stuck
thankz

laserlight

Could you explain further?

It looks like your user table is unnecessary.

I suggest that:
1. Give the scenario without mentioning the tables or code.
e.g.
"I want to make a quiz.
This quiz will have 100 questions, chosen randomly from a set of 1800 questions."

Explain the tables in detail
e.g.
Table: questions
id INT NOT NULL AUTO_INCREMENT
question TEXT
answer TEXT
Explain the process (algorithm) that you intend to use.
This is roughly what you have tried to do.
Then say what problems you have.

If you're trying to find out if what you intend to do will work, then my advice is DONT ASK YET.
Give it a try first, and if it doesnt work, then ask.

aznur95

okay,
user table will store all user information.

table USER

originator varchar(10) primary key
pointDay int(11)
pointWeek int(11)
questionSequence int(4)

table QUESTION

questId int(4) primary key
question text
answer varchar(2)

i need to generate 100 unique questId and store in questionSequence.

😕

Weedpacket

// For your numbers to all be unique, you
// have to remember all the numbers
// you've already drawn.

$random_numbers = array();

// A few parameters to play with...
$minimum_random = 0;
$maximum_random = 1000;
$number_of_randoms = 100;

// ...because a certain check would be advisable.
if($maximum_random-$minimum_random+1>$number_of_randoms)
{ die("I can't select ".$number_of_randoms." from a list of only ".($maximum_random-$minimum_random+1).".");

// So we keep going until we have enough
while(count($random_numbers)<$number_of_randoms)
{
    $random = mt_rand($minimum_random, $maximum_random);
    // If we already have this one, try again
    if(in_array($random, $random_numbers))
        continue;
    // Otherwise, we have it now
    $random_numbers[] = $random;
}

So there are your random numbers. There are other ways to do it, and some of them are likely to be better than that crude (though straightforward) bit of code.