If length of result

[Name]

Current:

  echo "<td width=20%>" . substr($row['CNotes'],0, 100) . " </td>";

Desired result:

  echo "<td width=20%>" . substr($row['CNotes'],0, 100) . IF LENGTH(CNOTES)>100 THEN "CLICK HERE TO VIEW MORE"" </td>";

[Name]

Or if it is over 100, just "..." added to the end. Something to show there is more. I don't know how to add an if after the " . "

[Old Pedant]

Nothing to do with MySQL. This is exclusively a PHP question.

The answer is the same if no database is involved.

$cnotes =  $row["CNotes"];
echo "<td width=20%>" . substr($cnotes,0, 100);
if ( strlen($cnotes) > 100 ) 
{
    echo '<a href="showMore.php?id=' . $row["ID"] . '">... CLICK HERE TO VIEW MORE</a>';
}
echo "</td>";

That shows having the user open a separate page to "view more" (using a hypothetical ID field from your DB table).

But if you instead wanted to use JavaScript to do the "show more", then you'd need to figure out the right JS code to drop in there. NOTE: Of course, if somebody has JS disabled, that's maybe not a viable answer.

EDIT: Corrected the error iBall showed. But I don't expect the above answer to be used, anyway. Almost surely you are going to want a better answer. But it's hard to give that without knowing WHAT you want. Oh, and I should have given the caveat that I don't code in PHP. If you had asked for a MySQL answer, I think I would get that right.