For selectExpr, how are you using it?  getRecords() runs a lot of extra code, I'm wondering if calling mysql_select_query() directly would provide even more performance?

Not frequently, but mostly when there's a table with large text or blob fields that we want to exclude when fetching a bunch of records for memory sake, but we still want to take advantage of some of the extra getRecords() options.

While I was in there, I thought I'd mention a few other enhancements that I added over the years in case you want to incorporate any of them.

https://www.interactivetools.com/forum/forum-posts.php?A-Few-Potential-Enhancements-82871

mysql_where(): support searching for NULL values

elseif (is_null($value)) {
    $where .= "`$fieldName` IS NULL AND ";
}

_getRecords_getQuery(): support selecting only part of the table for performance with large tables, support forcing an index

if (@$options['selectExpr']) {
    $selectFields = "`{$options['tableName']}`." . $options['selectExpr'];
}

// create query
$query = "SELECT $selectFields\n";
$query .= "FROM `" .DB::$tablePrefix. "{$options['tableName']}` as `{$options['tableName']}`\n";
$query .= (@$options['useIndex']) ? "USE INDEX ({$options['useIndex']})\n" : '';
$query .= $LEFT_JOIN;

...

_getRecords_getCountQuery(): useIndex same as getQuery()

isValidEmail(): prevent leading/trailing spaces from throwing an error since they don't break any mail functions I've found

$input = trim(is_string($input) ? $input : (string) $input);

I couldn't figure out why it wasn't retrying on fail recently until I just noticed that the DB::isConnected() function only checks that the $mysqli variable has been instantiated. When DB::connect() throws an exception, it doesn't reset the $mysqli variable. So when I check DB::isConnected() it always returns true after the first attempt. I created a workaround to call DB::disconnect() after a failed attempt, but it would seem that DB::isConnected() should be refactored to actually check that we have a connection, not that it was just attempted.

I changed it to use md5() as that will still allow multiple installs on the same server, but the same install dir across multiple servers will generate the same value.

$suffix    = strtolower(substr(md5(CMS_ROOT_DIR), -6));

There may be a better way to handle it.

I did notice one small bug hasn't been fixed in mail_functions.php on line 230. The variable set at the top is called $oldEncoding, not $mbEncoding.

elseif (@$fieldSchema['optionsType'] == 'table' && empty($selectedValues)) {
  $valuesToLabels = [];
}
else {
  $listOptions    = getListOptionsFromSchema($fieldSchema, null, false, $selectedValues);
  $values         = array_pluck($listOptions, '0');
  $labels         = array_pluck($listOptions, '1');
  $valuesToLabels = $listOptions ? array_combine($values, $labels) : [];
}

I have display_errors turned off. I'm confused why I would want text printed all over the page every time an error is logged? Isn't that the entire reason to log the errors and not display them in environments like prod?

Or maybe I'm missing something?

What I've done is add a line to check for headers which most load balancers populate. There may also be additional enhancements that could also be added here for different configurations, but this worked for me on Heroku and AWS.

function isHTTPS() {
  if (isset($_SERVER['HTTPS'])       && $_SERVER['HTTPS']       == 'on') { return true; }
  if (isset($_SERVER['SERVER_PORT']) && $_SERVER['SERVER_PORT'] == 443)  { return true; }
  if (isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && @$_SERVER['HTTP_X_FORWARDED_PROTO'] == 'https')  { return true; }
  if (isset($_SERVER['HTTP_X_FORWARDED_PORT']) && @$_SERVER['HTTP_X_FORWARDED_PORT'] == 443)  { return true; }
  return false;
}

• You have a table (A) with a field (F) that is a List that is set to Get Options from Database (advanced) from table (B)
• Field F is set to null in all records in the table.
• You run getRecords() on table A with loadPseudoFields set to true.

In _getRecords_addPseudoFields() it will call getListOptionsFromSchema() with $selectedValues as an empty array.

This runs a query on table B with no WHERE clause, so it pulls the first 1000 rows from the table which can take a few seconds to run on a large table.

But there's no need to populate the label on a null value, so the whole thing doesn't even need to be run.

So what I've done is edit line 602+ as such:

elseif (!empty($selectedValues)) {
  $listOptions    = getListOptionsFromSchema($fieldSchema, null, false, $selectedValues);
  $values         = array_pluck($listOptions, '0');
  $labels         = array_pluck($listOptions, '1');
  $valuesToLabels = $listOptions ? array_combine($values, $labels) : [];
}
else {
  continue;
}