diff --git a/examples/sql/sqlbrowser/browser.h b/examples/sql/sqlbrowser/browser.h
index 95c7079539d..d723bbb5553 100644
--- a/examples/sql/sqlbrowser/browser.h
+++ b/examples/sql/sqlbrowser/browser.h
@@ -22,8 +22,8 @@ class Browser : public QWidget
 {
     Q_OBJECT
 public:
-    Browser(QWidget *parent = nullptr);
-    ~Browser();
+    explicit Browser(QWidget *parent = nullptr);
+    ~Browser() override;
 
     QSqlError addConnection(const QString &driver, const QString &dbName, const QString &host,
                             const QString &user, const QString &passwd, int port);
diff --git a/examples/sql/sqlbrowser/connectionwidget.h b/examples/sql/sqlbrowser/connectionwidget.h
index a00296f3c5d..bd481f30758 100644
--- a/examples/sql/sqlbrowser/connectionwidget.h
+++ b/examples/sql/sqlbrowser/connectionwidget.h
@@ -14,8 +14,8 @@ class ConnectionWidget : public QWidget
 {
     Q_OBJECT
 public:
-    ConnectionWidget(QWidget *parent = nullptr);
-    ~ConnectionWidget();
+    explicit ConnectionWidget(QWidget *parent = nullptr);
+    ~ConnectionWidget() override;
 
     QSqlDatabase currentDatabase() const;
 
diff --git a/examples/sql/sqlbrowser/qsqlconnectiondialog.h b/examples/sql/sqlbrowser/qsqlconnectiondialog.h
index 70dec9e9a86..1ea1ae4a927 100644
--- a/examples/sql/sqlbrowser/qsqlconnectiondialog.h
+++ b/examples/sql/sqlbrowser/qsqlconnectiondialog.h
@@ -19,8 +19,8 @@ class QSqlConnectionDialog : public QDialog
 {
     Q_OBJECT
 public:
-    QSqlConnectionDialog(QWidget *parent = nullptr);
-    ~QSqlConnectionDialog();
+    explicit QSqlConnectionDialog(QWidget *parent = nullptr);
+    ~QSqlConnectionDialog() override;
 
     QString driverName() const;
     QString databaseName() const;