diff --git a/UPGRADE.md b/UPGRADE.md
index ca6326eb27..9cf6908677 100644
--- a/UPGRADE.md
+++ b/UPGRADE.md
@@ -72,6 +72,23 @@ all drivers and middleware.
 
 # Upgrade to 4.3
 
+## Deprecated `AbstractAsset` namespace-related methods and property
+
+The following namespace-related methods and property have been deprecated:
+
+- `AbstractAsset::getNamespaceName()`
+- `AbstractAsset::isInDefaultNamespace()`
+- `AbstractAsset::$_namespace`
+
+In order to identify the namespace of an object, use the following methods instead:
+
+```php
+$qualifier = $table->getObjectName()->getQualifier();
+```
+
+If the return value is not null, then it will contain the identifier representing the namespace name – its value and
+whether it's quoted.
+
 ## `Table::__construct()` marked as internal
 
 The `Table::__construct()` method has been marked as internal. Use `Table::editor()` to instantiate an editor and
diff --git a/psalm.xml.dist b/psalm.xml.dist
index cd73308464..43c1f7347a 100644
--- a/psalm.xml.dist
+++ b/psalm.xml.dist
@@ -62,8 +62,25 @@
                 -->
                 <referencedMethod name="Doctrine\DBAL\Schema\AbstractAsset::getNameParser" />
                 <referencedMethod name="Doctrine\DBAL\Schema\AbstractAsset::setName" />
+
+                <!--
+                    https://github.com/doctrine/dbal/pull/6664
+                    TODO: remove in 5.0.0
+                -->
+                <referencedMethod name="Doctrine\DBAL\Schema\AbstractAsset::getNamespaceName" />
+                <referencedMethod name="Doctrine\DBAL\Schema\AbstractAsset::isInDefaultNamespace" />
             </errorLevel>
         </DeprecatedMethod>
+        <DeprecatedProperty>
+            <errorLevel type="suppress">
+                <!--
+                    https://github.com/doctrine/dbal/pull/6664
+                    TODO: remove in 5.0.0
+                -->
+                <referencedProperty name="Doctrine\DBAL\Schema\AbstractAsset::$_namespace" />
+                <referencedProperty name="Doctrine\DBAL\Schema\Table::$_namespace" />
+            </errorLevel>
+        </DeprecatedProperty>
         <DocblockTypeContradiction>
             <errorLevel type="suppress">
                 <!--
diff --git a/src/Schema/AbstractAsset.php b/src/Schema/AbstractAsset.php
index 3a762c2600..bc0122b089 100644
--- a/src/Schema/AbstractAsset.php
+++ b/src/Schema/AbstractAsset.php
@@ -12,6 +12,7 @@
 use Doctrine\DBAL\Schema\Name\OptionallyQualifiedName;
 use Doctrine\DBAL\Schema\Name\Parser;
 use Doctrine\DBAL\Schema\Name\UnqualifiedName;
+use Doctrine\Deprecations\Deprecation;
 
 use function array_map;
 use function assert;
@@ -40,6 +41,8 @@ abstract class AbstractAsset
 
     /**
      * Namespace of the asset. If none isset the default namespace is assumed.
+     *
+     * @deprecated Use {@see NamedObject::getObjectName()} and {@see OptionallyQualifiedName::getQualifier()} instead.
      */
     protected ?string $_namespace = null;
 
@@ -133,9 +136,18 @@ protected function setName(?Name $name): void
 
     /**
      * Is this asset in the default namespace?
+     *
+     * @deprecated
      */
     public function isInDefaultNamespace(string $defaultNamespaceName): bool
     {
+        Deprecation::triggerIfCalledFromOutside(
+            'doctrine/dbal',
+            'https://github.com/doctrine/dbal/pull/6664',
+            '%s is deprecated and will be removed in 5.0.',
+            __METHOD__,
+        );
+
         return $this->_namespace === $defaultNamespaceName || $this->_namespace === null;
     }
 
@@ -143,9 +155,19 @@ public function isInDefaultNamespace(string $defaultNamespaceName): bool
      * Gets the namespace name of this asset.
      *
      * If NULL is returned this means the default namespace is used.
+     *
+     * @deprecated Use {@see NamedObject::getObjectName()} and {@see OptionallyQualifiedName::getQualifier()} instead.
      */
     public function getNamespaceName(): ?string
     {
+        Deprecation::triggerIfCalledFromOutside(
+            'doctrine/dbal',
+            'https://github.com/doctrine/dbal/pull/6664',
+            '%s is deprecated and will be removed in 5.0. Use NamedObject::getObjectName()'
+                . ' and OptionallyQualifiedName::getQualifier() instead.',
+            __METHOD__,
+        );
+
         return $this->_namespace;
     }