Use array_key_first()

Same results, but simpler and faster code.

Note array_key_first() is available on PHP 7.3+, which is thankfully the minimum PHP version required by CodeIgniter.

Author: vlakoff

system/Database/Query.php

@@ -281,7 +281,7 @@ protected function compileBinds()
 
         $binds = (array) $this->binds;
 
-        if (is_int(key(array_slice($binds, 0, 1)))) {
+        if (is_int(array_key_first($binds))) {
             $bindCount = count($binds);
             $ml        = strlen($this->bindMarker);