diff --git a/tests/php-unit-tests/unitary-tests/core/TestGLATest.delta.xml b/tests/php-unit-tests/unitary-tests/core/TestGLATest.delta.xml
new file mode 100644
index 000000000..a69608f08
--- /dev/null
+++ b/tests/php-unit-tests/unitary-tests/core/TestGLATest.delta.xml
@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<itop_design xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1.7">
+  <classes>
+    <class id="Person">
+      <fields>
+        <field id="tested_attribute" xsi:type="AttributeString" _delta="define">
+          <sql>tested_attribute</sql>
+          <default_value/>
+          <is_null_allowed>true</is_null_allowed>
+        </field>
+      </fields>
+    </class>
+  </classes>
+</itop_design>
diff --git a/tests/php-unit-tests/unitary-tests/core/TestGLATest.php b/tests/php-unit-tests/unitary-tests/core/TestGLATest.php
new file mode 100644
index 000000000..10e876327
--- /dev/null
+++ b/tests/php-unit-tests/unitary-tests/core/TestGLATest.php
@@ -0,0 +1,39 @@
+<?php
+/*
+ * @copyright   Copyright (C) 2010-2023 Combodo SARL
+ * @license     http://opensource.org/licenses/AGPL-3.0
+ */
+
+namespace Combodo\iTop\Test\UnitTest\Core;
+
+use Combodo\iTop\Test\UnitTest\ItopCustomDatamodelTestCase;
+use DBObjectSet;
+use DBSearch;
+use MetaModel;
+
+/**
+ * Tests of the DBSearch class.
+ * <ul>
+ * <li>MakeGroupByQuery</li>
+ * </ul>
+ *
+ * @runTestsInSeparateProcesses
+ * @preserveGlobalState disabled
+ * @backupGlobals disabled
+ */
+class TestGLATest extends ItopCustomDatamodelTestCase
+{
+	/**
+	 * @inheritDoc
+	 */
+	public function GetDatamodelDeltaAbsPath(): string
+	{
+		return APPROOT.'tests/php-unit-tests/unitary-tests/core/TestGLATest.delta.xml';
+	}
+
+	public function testFoo()
+	{
+		static::assertFalse(MetaModel::IsValidAttCode('Person', 'non_existing_attribute'));
+		static::assertTrue(MetaModel::IsValidAttCode('Person', 'tested_attribute'));
+	}
+}