CODEWITHSUNDEEP
phpmysql
sharataka
sharataka

Reputation: 5132

How do I update consecutive rows in a mysql database using php?

I have a list of values I am trying to enter into a mysql database with a dynamic number of rows. The variables are stored in $box1, $box2, and so on. I am trying to use UPDATE to put in the right value ($box1 in the first row selected, $box2 in the second row selected, and so on) in each consecutive row of the table. I’m not sure what code I have to type in the “while” loop to make this happen.

    <?php


        // Retrieve data from Query String
    $box1 = $_GET['box1'];
    $box2 = $_GET['box2'];
    $box3 = $_GET['box3'];
    $box4 = $_GET['box4'];
    $box5 = $_GET['box5'];
    $session = session_id();


        //build query
    $query = "SELECT * FROM sessionid WHERE sessionid='$session' ";

        //Execute query
    $qry_result = mysql_query($query) or die(mysql_error());

        // Insert the right quantity in each row for each consecutive box 
        $i=1;
        while($row = mysql_fetch_array($qry_result)){
            mysql_query("UPDATE `sessionid` SET `qt`='$box' .$i . '' WHERE `sessionid`='$session' ");
            $i++;
            }


    ?>

I am now inputting the data from the url on the previous page into an array $box[1]. I keep getting an error saying: Parse error: syntax error, unexpected '"', expecting T_STRING or T_VARIABLE or T_NUM_STRING in /home/content/c/a/s/cashme/html/buylooper/change-qt.php on line 13. Line 13 refers to the line that UPDATE query. Any tips?

//Retrieve data from Query String, input into array, and update table
        $count = $_SESSION['id'];
        for ($i=1; $i<$count; $i++){
                $box[$i] = $_GET['box'. $i .''];
            mysql_query("UPDATE `sessionid` SET `qt`='$box["'. $i .'"]' WHERE `sessionid`='$session' AND `id`='$i' ");
            echo $box[$i];
        }

Upvotes: 0

Views: 800

Answers (3)

Your Common Sense
Your Common Sense

Reputation: 157919

A most basic thing you have to learn by heart:

There are no consecutive rows in the database.

All the rows are completely random.
And you cannot rely on their natural order by any means.

To update a certain row you have to identify it with some unique field. Mysql's standard auto incremented id is the best choice.

Always store the row's id in the form, to be able to know which row current value belongs to.
Make your form like this

<input type="text" name"box[1]" value="20">

where 1 is an actual row's id

Also note that all data manipulations have to be performed using POST method, not GET.

So, in the $_POST['box'] you will have an array of pairs id => value and can easily construct the update query out of them.

Upvotes: 2

OM The Eternity
OM The Eternity

Reputation: 16234

U need

"UPDATE `sessionid` SET `qt`="'.$box.$i . '" WHERE `sessionid`="'.$session.'"

Also You should Store the values in Array rather than separate $box variables

u shld use

$box[]

not 

$box1,$box2, etc...

Upvotes: 0

Raptor
Raptor

Reputation: 54248

Why don't you store your variables $box1 to $box5` in an array instead of 5 variables?

Then you can use $boxes[$i] to call the related values.

Upvotes: 1

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