Question

If i’ve database my_table (id,word) as following

and i’ve some posted text called
$name and $comment then i want to know if $name and/or $comment have any words like words i’ve stored in my database my_table (id,word)

$name = "Manal Nor";
$comment = "Hello lovely world";

I can now apply it for only one entry for example $name

$name = "Manal Nor"; // As example no bad words

$sql    = "SELECT * FROM my_table";
$result = mysql_query($sql);

$nameArray = explode(" ", $name);
$countname = count($nameArray);
$checkname = 0;

while ($row = mysql_fetch_assoc($result)) {

    for ($i=0;$i<$countname;$i++) {

        if (strcasecmp($nameArray[$i], $row['word']) == 0) {
            $checkname = 1;
        }

    }

}

if ($checkname == 1) {
    echo "banned";
    exit;
}
else {
    echo "passed";
}

but now the question how to apply it for both $name and/or $comment so that i can give echo "banned"; if either $name and/or $comment have any of the bad words in my_table

Answer 1

The trick here would be to split both variables on word characters with preg_split() and use the resultant arrays to form an IN() clause to your query.

// Strip non-alpha, space characters
$name = preg_replace("/[^a-zA-Z ]/", "", $name);
$comment = preg_replace("/[^a-zA-Z ]/", "", $comment);

$namewords = explode(" ", $name);
$commentwords = explode(" ", $comment);
// Stick them together and escape
$allwords = array_merge($namewords, $commentwords);

// Surround each word in quotes
$allwords = array_unique($allwords);
$allwords = array_map(function($w) {return "'$w'";}, $allwords);
$allwords = implode(",", $allwords);    

// Builds a query like 
// SELECT * FROM my_table WHERE word IN ('all', 'words', 'from', 'comment', 'and', 'name');
$result = mysql_query("SELECT word FROM my_table WHERE word IN($allwords)");

if ($result) {
   // If any rows were returned, the input contained a bad word.
   if (mysql_num_rows($result) > 0) {
      // Contains bad words.  Ban user.
   }
}