Create an id generator-CodePudding

I want to create an id, that contains int value and string value, with 4 characters and it must be unique because it's a primarykey.

for example: 1g81 or h39d.

I am using laravel 8.8.

CodePudding user response：

In PHP use this:

function unique_code($limit)
{
  return substr(base_convert(sha1(uniqid(mt_rand())), 16, 36), 0, $limit);
}
echo unique_code(4);

$limit = number of characters

or in laravel you can use only this:

define this on the top

use Illuminate\Support\Str;

and use this

$uniqid = Str::random(4);

CodePudding user response：

In MySQL,the uuid() function generates a pseudo random string which looks like da5c3e92-c06e-11ec-a98b-000c29087583. With the left() function, we can fetch the first 4 characters. To demonstrate, create a table named idtest. Then insert into the table with characters generated with the said functions. If case the generated string is already used, we can use a loop to generate another one to gurantee its uniqueness.

create table idtest(id char(4) primary key);
delimiter //
drop procedure if exists generate_id //
create procedure generate_id(num int unsigned)
begin
declare count int default 0;

while count<num do
    lp:loop
    select left(uuid(),4) into @id;
        if (select count(*) from idtest where id=@id ) =0 then
            insert idtest (id) values (@id);
            leave  lp;
        end if;
    end loop lp;
set count=count 1;
end while;
end//
call generate_id(100)// -- call the procedure to insert 100 strings into the table

CodePudding user response：

You Can use the below custom function to generate random strings with numbers too.

    $n=4;
function getName($n) {
    $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
    $randomString = '';
for ($i = 0; $i < $n; $i  ) {
    $index = rand(0, strlen($characters) - 1);
    $randomString .= $characters[$index];
}

return $randomString;

}

echo getName($n)

;

CodePudding user response：

Here's a simple method that will guarantee that your ID is always unique:

public function generateId(){
    $uuid = Uuid::generate(4)->string; //Webpaster UUID generator
    $id = explode('-', $uuid)[0]; //Taking first block of random strings/numbers that is separated with "-"

    //Check if ID unique, if not, generate another one with same logic
    while(YourModel::where('id', $id)->first()){
        $uuid = Uuid::generate(4)->string;
        $id = explode('-', $uuid)[0];
    }

    return $id;
}

This will basically re-generate the code each time one is already found in your database. The package used here is this one: https://github.com/webpatser/laravel-uuid

You can basically remove the package and use Laravel's random() method, and just keep the same logic for regenerating the string if it is already found in the database.