How to resolve problem with unique id PHP, ORACLE 12C - php

Question

Using PHP + Oracle 12c
I'm trying to insert many rows but i got an error "oci_execute(): ORA-00001: unique constraint (S95417.FIRMA__IDX)" This is strange for me because in loop i'm getting last id and incrementing it.
I used debbuger and (On INSERT) i'm getting last id but incrementing is not working.
Could you tell me why?
Data which i added
INSERT INTO FIRMA VALUES(18,MICROSOFT,2432213715,2020-03-26,23)
INSERT INTO FIRMA VALUES(19,APPLE,7512202082,2020-03-26,42)
SELECT NVL(MAX(firmaid),0)+1
I made code very similar using that for other tables and it's working fine.
My code:
$ile_razy = $_POST['liczba_powtorzen'];
$firma = "SELECT * FROM FIRMA";
$c = oci_connect($username, $password, $database);
if (!$c) {
$m = oci_error();
trigger_error('Could not connect to database: '. $m['message'], E_USER_ERROR);
}
$file = 'firma.txt';
$current = file_get_contents($file);
for ($i = 1; $i <= $ile_razy; $i++) {
$nazwa = randCompanyName();
$nip = randNIP();
$dataWspolpracy = date("Y-m-d");
$ids_array = array();
$adresid = "SELECT adresid FROM ADRES";
$stmtt = oci_parse($c, $adresid);
$result = oci_execute($stmtt);
while($row = oci_fetch_array($stmtt))
{
$ids_array[] = $row['ADRESID'];
}
$randIndex = array_rand($ids_array);
$adresId = $ids_array[$randIndex];
// HERE IS PROBLEM
$firmaQuery = "INSERT INTO FIRMA SELECT NVL(MAX(firmaid),0) + 1,'$nazwa', '$nip', '$dataWspolpracy', '$adresId' from FIRMA";
$ex = oci_parse($c,$firmaQuery);
// "zapytanie" is working fine
$zapytanie = "SELECT NVL(MAX(firmaid),0)+1 from FIRMA";
$stmt = oci_parse($c, $zapytanie);
$results = oci_execute($stmt);
while($row = oci_fetch_assoc($stmt)){
$rowid = $row["NVL(MAX(FIRMAID),0)+1"];
}
$firmaIdForTxt = "INSERT INTO FIRMA VALUES(".$rowid.",".$nazwa.",".$nip.",".$dataWspolpracy.",".$adresId.")";
echo $rowid. ", ";
oci_execute($ex);
$current .= $i. ".".$firmaIdForTxt."\n";
file_put_contents($file, $current);
}
In my db
I have changed that but error still appears

Answer 1

You can make your FIRMAID an identity column : Oracle will handle the increment internally, and it is much more safer for your data.
Then you can insert your data with this query :
INSERT INTO FIRMA(nazwa, nip, datawspolpracy, adresid) VALUES('$nazwa', '$nip', '$dataWspolpracy', '$adresId')
NOTE : this is for a quick answer, for a safer solution and avoid SQL injections, use prepared statements : PHP oci examples (See example #2)