diff --git a/cmake/qet_compilation_vars.cmake b/cmake/qet_compilation_vars.cmake
index 60fddcf55..398cdce8c 100644
--- a/cmake/qet_compilation_vars.cmake
+++ b/cmake/qet_compilation_vars.cmake
@@ -325,6 +325,7 @@ set(QET_SRC_FILES
   ${QET_DIR}/sources/autoNum/ui/selectautonumw.cpp
   ${QET_DIR}/sources/autoNum/ui/selectautonumw.h
 
+  ${QET_DIR}/sources/dataBase/legacyelementtypes.h
   ${QET_DIR}/sources/dataBase/projectdatabase.cpp
   ${QET_DIR}/sources/dataBase/projectdatabase.h
   ${QET_DIR}/sources/dataBase/sqlreadonly.cpp
diff --git a/sources/dataBase/legacyelementtypes.h b/sources/dataBase/legacyelementtypes.h
new file mode 100644
index 000000000..51943996b
--- /dev/null
+++ b/sources/dataBase/legacyelementtypes.h
@@ -0,0 +1,69 @@
+/*
+	Copyright 2006-2026 The QElectroTech Team
+	This file is part of QElectroTech.
+
+	QElectroTech is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 2 of the License, or
+	(at your option) any later version.
+
+	QElectroTech is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with QElectroTech.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#ifndef LEGACYELEMENTTYPES_H
+#define LEGACYELEMENTTYPES_H
+
+#include <QRegularExpression>
+#include <QString>
+
+/**
+	Element type names in queries saved by versions before June 2022.
+	The project database then held Element::linkTypeToString() ("Simple",
+	"Terminale", ...); since it holds ElementData::typeToString()
+	("simple", "terminal", ...). SQLite compares text case-sensitively, so
+	a nomenclature table saved with element_type = 'Simple' silently lost
+	every simple element, and its continuation tables were deleted as
+	empty.
+*/
+namespace LegacyElementTypes
+{
+	/**
+		@return query with every element_type = '<old name>' comparison
+		rewritten to the current name. Anything else is left as it is,
+		so a query saved by a current version comes back unchanged.
+	*/
+	inline QString upgradeQuery(const QString &query)
+	{
+		static const QRegularExpression re(QStringLiteral(
+			"element_type\\s*=\\s*'(Simple|NextReport|PreviousReport|Master"
+			"|Slave|Terminale|Thumbnail)'"));
+
+		QString upgraded = query;
+		auto it = re.globalMatch(query);
+		int shift = 0;
+		while (it.hasNext())
+		{
+			const auto match = it.next();
+			const QString old_name = match.captured(1);
+			QString new_name;
+			if      (old_name == QLatin1String("Simple"))         new_name = QStringLiteral("simple");
+			else if (old_name == QLatin1String("NextReport"))     new_name = QStringLiteral("next_report");
+			else if (old_name == QLatin1String("PreviousReport")) new_name = QStringLiteral("previous_report");
+			else if (old_name == QLatin1String("Master"))         new_name = QStringLiteral("master");
+			else if (old_name == QLatin1String("Slave"))          new_name = QStringLiteral("slave");
+			else if (old_name == QLatin1String("Terminale"))      new_name = QStringLiteral("terminal");
+			else                                                  new_name = QStringLiteral("thumbnail");
+
+			upgraded.replace(match.capturedStart(1) + shift, old_name.size(), new_name);
+			shift += new_name.size() - old_name.size();
+		}
+		return upgraded;
+	}
+}
+
+#endif // LEGACYELEMENTTYPES_H
diff --git a/sources/qetgraphicsitem/ViewItem/projectdbmodel.cpp b/sources/qetgraphicsitem/ViewItem/projectdbmodel.cpp
index ca07e5ba8..a201fcb02 100644
--- a/sources/qetgraphicsitem/ViewItem/projectdbmodel.cpp
+++ b/sources/qetgraphicsitem/ViewItem/projectdbmodel.cpp
@@ -19,6 +19,7 @@
 
 #include <algorithm>
 
+#include "../../dataBase/legacyelementtypes.h"
 #include "../../dataBase/projectdatabase.h"
 #include "../../qetapp.h"
 #include "../../qetinformation.h"
@@ -294,7 +295,9 @@ void ProjectDBModel::fromXml(const QDomElement &element)
 		return;
 	
 	setIdentifier(element.firstChildElement("identifier").text());
-	setQuery(element.firstChildElement("query").text());
+		//A query saved before June 2022 names element types the old way
+	setQuery(LegacyElementTypes::upgradeQuery(
+				 element.firstChildElement("query").text()));
 	
 	//Index 0,0
 	auto index_00 = element.firstChildElement("index00");
diff --git a/tests/qttest/CMakeLists.txt b/tests/qttest/CMakeLists.txt
index 66074282d..d2437661d 100644
--- a/tests/qttest/CMakeLists.txt
+++ b/tests/qttest/CMakeLists.txt
@@ -104,6 +104,13 @@ add_test(NAME tst_textgrid COMMAND tst_textgrid)
 target_include_directories(tst_textgrid PRIVATE ${QET_DIR}/sources)
 target_link_libraries(tst_textgrid PRIVATE Qt::Test)
 
+# legacyelementtypes.h is header-only: the rewrite of element type names in
+# nomenclature queries saved before June 2022.
+add_executable(tst_legacyelementtypes tst_legacyelementtypes.cpp)
+add_test(NAME tst_legacyelementtypes COMMAND tst_legacyelementtypes)
+target_include_directories(tst_legacyelementtypes PRIVATE ${QET_DIR}/sources)
+target_link_libraries(tst_legacyelementtypes PRIVATE Qt::Test)
+
 add_executable(
   tst_qetpalette
   tst_qetpalette.cpp
diff --git a/tests/qttest/tst_legacyelementtypes.cpp b/tests/qttest/tst_legacyelementtypes.cpp
new file mode 100644
index 000000000..bc36725e1
--- /dev/null
+++ b/tests/qttest/tst_legacyelementtypes.cpp
@@ -0,0 +1,60 @@
+/*
+	Copyright 2006-2026 The QElectroTech Team
+	This file is part of QElectroTech.
+
+	QElectroTech is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 2 of the License, or
+	(at your option) any later version.
+
+	QElectroTech is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with QElectroTech.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#include "dataBase/legacyelementtypes.h"
+
+#include <QTest>
+
+class TestLegacyElementTypes : public QObject
+{
+	Q_OBJECT
+
+	private slots:
+	void upgradesOldNames_data()
+	{
+		QTest::addColumn<QString>("saved");
+		QTest::addColumn<QString>("expected");
+
+		// The WHERE clause industrial.qet's parts list was saved with.
+		QTest::newRow("simple, with sub types")
+				<< "WHERE ( element_type = 'Simple' OR element_sub_type = 'coil') ORDER BY label"
+				<< "WHERE ( element_type = 'simple' OR element_sub_type = 'coil') ORDER BY label";
+		QTest::newRow("terminal and master, lengths change")
+				<< "element_type = 'Terminale' OR element_type = 'Master' OR element_type = 'Simple'"
+				<< "element_type = 'terminal' OR element_type = 'master' OR element_type = 'simple'";
+		QTest::newRow("reports and thumbnail")
+				<< "element_type='NextReport' OR element_type =  'PreviousReport' OR element_type = 'Thumbnail'"
+				<< "element_type='next_report' OR element_type =  'previous_report' OR element_type = 'thumbnail'";
+		QTest::newRow("current names unchanged")
+				<< "element_type = 'simple' OR element_type = 'terminal'"
+				<< "element_type = 'simple' OR element_type = 'terminal'";
+		QTest::newRow("the word elsewhere unchanged")
+				<< "WHERE label = 'Simple' OR designation = 'Master'"
+				<< "WHERE label = 'Simple' OR designation = 'Master'";
+		QTest::newRow("empty") << "" << "";
+	}
+
+	void upgradesOldNames()
+	{
+		QFETCH(QString, saved);
+		QFETCH(QString, expected);
+		QCOMPARE(LegacyElementTypes::upgradeQuery(saved), expected);
+	}
+};
+
+QTEST_APPLESS_MAIN(TestLegacyElementTypes)
+#include "tst_legacyelementtypes.moc"