diff --git a/lib/Doctrine/ORM/Mapping/Driver/AnnotationDriver.php b/lib/Doctrine/ORM/Mapping/Driver/AnnotationDriver.php
index a0968014265..3d83deabf9f 100644
--- a/lib/Doctrine/ORM/Mapping/Driver/AnnotationDriver.php
+++ b/lib/Doctrine/ORM/Mapping/Driver/AnnotationDriver.php
@@ -87,6 +87,7 @@ public function loadMetadataForClass($className, PersistenceClassMetadata $metad
                 continue;
             }
 
+            unset($classAnnotations[$key]);
             $classAnnotations[get_class($annot)] = $annot;
         }
 
diff --git a/lib/Doctrine/ORM/Persisters/Entity/SingleTablePersister.php b/lib/Doctrine/ORM/Persisters/Entity/SingleTablePersister.php
index bc9becac1cb..af454b666bd 100644
--- a/lib/Doctrine/ORM/Persisters/Entity/SingleTablePersister.php
+++ b/lib/Doctrine/ORM/Persisters/Entity/SingleTablePersister.php
@@ -135,13 +135,13 @@ protected function getSelectConditionDiscriminatorValueSQL(): string
         $values = [];
 
         if ($this->class->discriminatorValue !== null) { // discriminators can be 0
-            $values[] = $this->conn->quote($this->class->discriminatorValue);
+            $values[] = $this->conn->quote((string) $this->class->discriminatorValue);
         }
 
         $discrValues = array_flip($this->class->discriminatorMap);
 
         foreach ($this->class->subClasses as $subclassName) {
-            $values[] = $this->conn->quote($discrValues[$subclassName]);
+            $values[] = $this->conn->quote((string) $discrValues[$subclassName]);
         }
 
         $discColumnName = $this->class->getDiscriminatorColumn()['name'];
diff --git a/lib/Doctrine/ORM/Query/Filter/SQLFilter.php b/lib/Doctrine/ORM/Query/Filter/SQLFilter.php
index 260b539d6d0..5c41fba8d7f 100644
--- a/lib/Doctrine/ORM/Query/Filter/SQLFilter.php
+++ b/lib/Doctrine/ORM/Query/Filter/SQLFilter.php
@@ -105,9 +105,7 @@ final public function getParameter(string $name): string
             throw FilterException::cannotConvertListParameterIntoSingleValue($name);
         }
 
-        $param = $this->parameters[$name];
-
-        return $this->em->getConnection()->quote($param['value'], $param['type']);
+        return $this->em->getConnection()->quote((string) $this->parameters[$name]['value']);
     }
 
     /**
@@ -133,7 +131,7 @@ final public function getParameterList(string $name): string
         $connection = $this->em->getConnection();
 
         $quoted = array_map(
-            static fn (mixed $value): string => (string) $connection->quote($value, $param['type']),
+            static fn (mixed $value): string => $connection->quote((string) $value),
             $param['value']
         );
 
diff --git a/lib/Doctrine/ORM/Query/SqlWalker.php b/lib/Doctrine/ORM/Query/SqlWalker.php
index 82cf19f5a40..153418450c5 100644
--- a/lib/Doctrine/ORM/Query/SqlWalker.php
+++ b/lib/Doctrine/ORM/Query/SqlWalker.php
@@ -461,7 +461,7 @@ private function generateDiscriminatorColumnConditionSQL(array $dqlAliases): str
             }
 
             foreach ($class->subClasses as $subclassName) {
-                $values[] = $conn->quote($this->em->getClassMetadata($subclassName)->discriminatorValue);
+                $values[] = $conn->quote((string) $this->em->getClassMetadata($subclassName)->discriminatorValue);
             }
 
             $sqlTableAlias = $this->useSqlTableAliases
@@ -1812,7 +1812,7 @@ public function walkUpdateItem($updateItem)
                 break;
 
             default:
-                $sql .= $this->conn->quote($newValue);
+                $sql .= $this->conn->quote((string) $newValue);
                 break;
         }