Echo php Variable from Mysql DB

Question

This is my Entire Code:

<?php

$query = "SELECT category FROM html where id = '1' ";
$result = mysql_query($query);
//while loop to display mysql table field values in html text boxes
$i = 0;
while ($row = mysql_fetch_row($result)) {
    $count = count($row);
    $y = 0;
    while ($y < $count) {
        $c_row = current($row);
        next($row);
        $y = $y + 1;
    }
    $i = $i + 1;
    $category = $c_row;
}
echo $category;
?>

I am showing the value of $categories variable using this code given below: Categories ( '. $categories; .' ) Actaully, the above code including to is not directly written in php web page. The code "Categories ( '. $categories; .' ) " is containing in the data base. Therefore $categories; cannot be parsed.

What I need is to show the Value:
Eg, if $categories = Books and Shelf;
I need, Categories ( '. $categories; .' ) :- Categories (Books and Shelf)

The $categories; value is already obtained in the php page before selecting from Mysql Table.

How can I parse php variable inserted in Mysql Row?

Categories ( '. $categories; .' ) :- The complete html tag is putted in the data base. The complete html code in the Mysql DB.

Answer 1

I'd like to know why you are storing variable references like that in your db but to solve it you could simply do something like this:

/*
assuming $string contains EXACTLY this
<h4>Categories ( '. $categories; .' ) </h4>
*/
echo str_replace('\'. $categories; .\'',$categories, $string);

If you commonly need to do word replacement on strings stored in a database I would recommend one of the following instead:

1) Use sprintf() and store your string like this:

$string = '<h4>Categories ( %s ) </h4>';
echo sprintf($string, $categories);

2) Use str_replace() and format string with braces around replacements:

$string = '<h4>Categories ( {categories} ) </h4>';
echo str_replace('{categories}', $categories, $string);

The benefit of that last one is you could store all kinds of variable references and replace them accordingly without having to know if they exist in the string:

$string = 'Hello, my name is {firstname} and I live in {city}, {state}';
$replace = ['{firstname}','{lastname}','{address}','{city}','{state}'];
$info = [
    'firstname' => 'john',
    'lastname'  => 'doe',
    'address'   => '123 main st',
    'city'      => 'somewhere',
    'state'     => 'IL'
];

echo str_replace($replace, $info, $string);

OUTPUT: Hello, my name is john and I live in somewhere, IL

Answer 2

A rewrite of your code:

1) Stop using MySQL_ fuctions, they are deprecated, insecure and should not be used . There are two alternatives; mysqli_ functions (Object orientated or Procedural) or PDO functionality (object orientated only)

2) Your question appears uclear, is your <h4> tag within <?php tags or is it just HTML? To output PHP you need to wrap the print / echo article in <?php tags to tell the server how to process this section of the code.

Likewise, you need to be sure the page is pocessed as a PHP page rather than just as an HTML page. So does the page name end with .php (such as page.php )?

3) For clarity: while ($row = mysql_fetch_row($result)) will only ever output one row at a time, each MySQL row with hold numerous columns .

4) It's very useful for you to indent your brackets correctly, typing four spaces ( not tab ) for each bracket contents, as exampled a litte bit below.

5) Your While loops are confused; you have too any brackets. Your value $c_row will only ever be the final value found in the row, but the row will only ever have one unqiue value in it -- that of the category column, because that's what's specified in the SQL query.

---

Rewrite:

/***
 * Fill with your own values, Address is usually 'Localhost'
 ***/
 // connction details:
 $conn = mysqli_connect(Address, User, Password, Database);

 // A numeric column (id) does not need values to be quoted.
 $query = "SELECT category FROM html where id = 1 ";
 // note the mysqli_ and use of new $conn variable setout above
 $result = mysqli_query($conn, $query);

 /***
  * Typical output from the above for returning two rows from 
  * the DB would be: 
  * $result[0]['category'] = "whatever_value"
  * $result[0][0] = "whatever_value"
  * $result[1]['category'] = "whatever_value_row2"
  * $result[1][0] = "whatever_value_row2"
  ***/

 // This will fetch all the rows, one row at a time, 
 // with array keys being the SQL column names 
 // (ignores numeric array keys). 
 while ($row = mysqli_fetch_array($result, MYSQLI_ASSOC)) 
       {
       // use definite named array key selectors to not need counters.
       $category = $row['category'];
       echo $category;     
       }

That would give you an output:

whatever_value
whatever_value_row2

To make your <h4> work as expected you can try replacing your echo with:

  print "<h4>Categories ( ". $category; ." ) </h4>";