here's a neat little function I whipped up to do HTML color coding of SQL strings.
<?php
function SQL_DEBUG( $query )
{
if( $query == '' ) return 0;
global $SQL_INT;
if( !isset($SQL_INT) ) $SQL_INT = 0;
$query = preg_replace("/['\"]([^'\"]*)['\"]/i", "'<FONT COLOR='#FF6600'>$1</FONT>'", $query, -1);
$query = str_ireplace(
array (
'*',
'SELECT ',
'UPDATE ',
'DELETE ',
'INSERT ',
'INTO',
'VALUES',
'FROM',
'LEFT',
'JOIN',
'WHERE',
'LIMIT',
'ORDER BY',
'AND',
'OR ', 'DESC',
'ASC',
'ON '
),
array (
"<FONT COLOR='#FF6600'><B>*</B></FONT>",
"<FONT COLOR='#00AA00'><B>SELECT</B> </FONT>",
"<FONT COLOR='#00AA00'><B>UPDATE</B> </FONT>",
"<FONT COLOR='#00AA00'><B>DELETE</B> </FONT>",
"<FONT COLOR='#00AA00'><B>INSERT</B> </FONT>",
"<FONT COLOR='#00AA00'><B>INTO</B></FONT>",
"<FONT COLOR='#00AA00'><B>VALUES</B></FONT>",
"<FONT COLOR='#00AA00'><B>FROM</B></FONT>",
"<FONT COLOR='#00CC00'><B>LEFT</B></FONT>",
"<FONT COLOR='#00CC00'><B>JOIN</B></FONT>",
"<FONT COLOR='#00AA00'><B>WHERE</B></FONT>",
"<FONT COLOR='#AA0000'><B>LIMIT</B></FONT>",
"<FONT COLOR='#00AA00'><B>ORDER BY</B></FONT>",
"<FONT COLOR='#0000AA'><B>AND</B></FONT>",
"<FONT COLOR='#0000AA'><B>OR</B> </FONT>",
"<FONT COLOR='#0000AA'><B>DESC</B></FONT>",
"<FONT COLOR='#0000AA'><B>ASC</B></FONT>",
"<FONT COLOR='#00DD00'><B>ON</B> </FONT>"
),
$query
);
echo "<FONT COLOR='#0000FF'><B>SQL[".$SQL_INT."]:</B> ".$query."<FONT COLOR='#FF0000'>;</FONT></FONT><BR>\n";
$SQL_INT++;
} ?>