PHP incrementing all IDs in a CSV - php

Question

thanks for reading!
I have an app that allows people to add, edit and delete items in a CSV. I've encountered a bug where if there are non-unique IDs and you try to edit or delete them, it will edit or delete all of them, as the system parses through the spreadsheet to find the ID - which also corresponds to the object's order when using it so the user must be able to change the ID
The solution I've come up with is quite simple, should the user edit an object and change its ID to one that already exists, then the system will take all of the objects with an ID bigger than or equal to the new ID and increment them all by one.
The following code is my if statement that checks whether the ID already exists
if($exists == "true") //does the $newImageID already exist in the gallery?
{
$table = fopen($fullURL,'r'); //$fullURL is the location of the CSV tested and works
$temp_table_two = fopen($tempURL,'w');
while (!feof($temp_table_two) ) {
$getid = fgetcsv($temp_table_two, 1024);
if($getid[0] >= $newImageID)
{
// $getid[0]++; //increase id in temp_table_two by 1 if it is > $newImageID
echo $getid[0];
}
}
fclose($table);
fclose($temp_table);
rename($tempURL,$fullURL);
}
This code takes place after fopen and before fclose. In context, $exists is either "true" or "false" (will change to boolean later on), the while loop parses through my $temp_table (a fopen) and if the first column object (the ID) is equal to or bigger than the one in the new ID then it is incremented. This means that the new object gets "slotted in" so to speak and pushes the rest down
Strangely my request is timing out after a long spinner after I execute this code and I have no idea what the problem is
Thanks for all your help in advance
EDIT: I have found the source of the problem is the while loop itself, should I comment everything out as such:
while (!feof($temp_table_two) ) {
$getid = fgetcsv($temp_table_two, 1024);
// if($getid[0] >= $newImageID)
// {
// // $getid[0]++; //increase id in temp_table_two by 1 if it is > $newImageID
// echo $getid[0];
// }
}
The code still doesn't work yet the only thing left to run is the loop that doesn't do anything
EDIT 2:
Following an answer, I did away with the temp table and just work from the table itself, this if statement is executed BEFORE adding the new data with its ID
if($exists == "true") //does the $newImageID already exist in the gallery?
{
$table = fopen($fullURL,'r+');
while (!feof($table) ) {
$getid = fgetcsv($table, 1024);
if($getid[0] >= $newImageID)
{
echo $getid[0];
$getid[0]++; //increase id in temp_table_two by 1 if it is > $newImageID
}
}
fclose($table);
}
The code no longer times out, but the items inside $getid[0] are not incremented. I have echoed them and it does echo all of the ID's equal to or bigger than my $newImageID but the $getid[0]++; doesn't seem to be affecting the CSV at all

Answer 1

You are testing if you reach the end of the temp file and that's wrong. You need to check the origin file and also read from it!
while (!feof($table) ) {
$getid = fgetcsv($table, 1024);

Answer 2

Try this:
if ($csv = fopen($temp_table_two, 'r+')) do {
$getid = fgetcsv($csv, 1024);
if($getid[0] >= $newImageID)
{
echo $getid[0]; // $getid[0]++;
}
} while (!feof($csv));
That will prevent your while loop from timing out due to being stuck in an infinite if there is a problem opening the file. feof will return true only if it reaches EOF, it will return false otherwise which will cause it to never be able to break out.
For actually writing your data back to the CSV file, your current code won't work as fgetcsv just gives you an array representation of a CSV line in the file. Writing to that array just changes the array, not back to the file.
For that, see this similar answer: Append data to middle line/row of a csv instead of the last line or row
or
http://php.net/manual/en/function.fputcsv.php