SQL CaseWhen/Sum + ContactRequest API fix

core/Driver/SQL/Expression/Sum.class.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace Driver\SQL\Expression;
+
+use Driver\SQL\Condition\Condition;
+
+class Sum extends Expression {
+
+  private $value;
+  private string $alias;
+
+  public function __construct($value, string $alias) {
+    $this->value = $value;
+    $this->alias = $alias;
+  }
+
+  public function getValue() { return $this->value; }
+  public function getAlias(): string { return $this->alias; }
+
+}