search every word in string with mysql and php - php

Question

I need to search every word of an string in the database. If an word exist it needs to be highlighted. The current script works, but needs a lot of memory for my server. I don't know how i make it easier, but maybe do you?
<?php
$total_messages = $_POST['total'] - 1;
for($x = 0; $x <= $total_messages; $x++)
{
//Search highlights
$result = $mysqli->query("SELECT * FROM highlights WHERE enabled=1")
while($row = $result->fetch_assoc())
{
//Vars for highlights
$highlight_txt = $row['value'];
$highlight_type = $row['type'];
$highlight_color = "black";
$highlight_title = null;
//If the text isnt empty
if($highlight_txt != null || $highlight_txt != "")
{
//Type highlights
if($highlight_type == "tree") //Tree type
{
$highlight_type = "18"; //Category number
$highlight_background = "pink"; //Background
if($row['option1'] != null)
{
$highlight_title = htmlentities($row['option1']);
}
}
else
{
$highlight_background = "yellow"; //Background
}
//Add highlight
$message = preg_replace("/\b($highlight_txt)\b/i", "<span class='bc_highlight' highlight-type='$highlight_type' highlight-value='$highlight_txt' style='background: $highlight_background; color: $highlight_color;' title=''>$highlight_txt</span>", $message);
}
}
echo $message; //Display the message
}

Answer 1

Why not doing something like this?
$messages = ["This is my message1","This is my message2"];
$highlights = [];
$result = $mysqli->query("SELECT * FROM highlights WHERE enabled=1")
while($row = $result->fetch_assoc()) {
$highlights[$row["value"]] = [
"type" => $row["type"],
"color" => $row["color"]
];
}
$callback = function($matches) use ($highlights) {
$word = $matches[1];
if(isset($highlights[$word])) {
$highlight = $highlights[$word];
return sprintf('<span style="color:%s">%s</span>',$highlight["color"],$word);
} else {
return $word;
}
};
foreach($messages as &$message) {
$message = preg_replace_callback("/(\w+)/i",$message,$callback);
}