diff --git a/tests/lib/DB/QueryBuilder/Partitioned/PartitionedQueryBuilderTest.php b/tests/lib/DB/QueryBuilder/Partitioned/PartitionedQueryBuilderTest.php
index 80ed5cd17e5..ae4bb832f27 100644
--- a/tests/lib/DB/QueryBuilder/Partitioned/PartitionedQueryBuilderTest.php
+++ b/tests/lib/DB/QueryBuilder/Partitioned/PartitionedQueryBuilderTest.php
@@ -27,6 +27,7 @@ class PartitionedQueryBuilderTest extends TestCase {
 	protected function setUp(): void {
 		if (PHP_INT_SIZE < 8) {
 			$this->markTestSkipped('Test requires 64bit');
+			return;
 		}
 		$this->connection = Server::get(IDBConnection::class);
 		$this->shardConnectionManager = Server::get(ShardConnectionManager::class);
@@ -36,7 +37,11 @@ class PartitionedQueryBuilderTest extends TestCase {
 	}
 
 	protected function tearDown(): void {
-		$this->cleanupDb();
+		// PHP unit also runs tearDown when the test is skipped, but we only initialized when using 64bit
+		// see https://github.com/sebastianbergmann/phpunit/issues/6394
+		if (PHP_INT_SIZE >= 8) {
+			$this->cleanupDb();
+		}
 		parent::tearDown();
 	}
 
diff --git a/tests/lib/Repair/RepairCollationTest.php b/tests/lib/Repair/RepairCollationTest.php
index ea6e70b2164..11fbecb0171 100644
--- a/tests/lib/Repair/RepairCollationTest.php
+++ b/tests/lib/Repair/RepairCollationTest.php
@@ -31,7 +31,6 @@ class TestCollationRepair extends Collation {
 /**
  * Tests for the converting of MySQL tables to InnoDB engine
  *
- *
  * @see \OC\Repair\RepairMimeTypes
  */
 #[\PHPUnit\Framework\Attributes\Group('DB')]
@@ -48,13 +47,13 @@ class RepairCollationTest extends TestCase {
 		parent::setUp();
 
 		$this->connection = Server::get(ConnectionAdapter::class);
-		$this->config = Server::get(IConfig::class);
 		if ($this->connection->getDatabaseProvider() !== IDBConnection::PLATFORM_MYSQL) {
 			$this->markTestSkipped('Test only relevant on MySql');
+			return;
 		}
 
 		$this->logger = $this->createMock(LoggerInterface::class);
-
+		$this->config = Server::get(IConfig::class);
 		$dbPrefix = $this->config->getSystemValueString('dbtableprefix');
 		$this->tableName = $this->getUniqueID($dbPrefix . '_collation_test');
 		$this->connection->prepare("CREATE TABLE $this->tableName(text VARCHAR(16)) COLLATE utf8_unicode_ci")->execute();
@@ -63,7 +62,11 @@ class RepairCollationTest extends TestCase {
 	}
 
 	protected function tearDown(): void {
-		$this->connection->getInner()->createSchemaManager()->dropTable($this->tableName);
+		$this->connection = Server::get(ConnectionAdapter::class);
+		if ($this->connection->getDatabaseProvider() === IDBConnection::PLATFORM_MYSQL) {
+			// tear down only needed on MySQL
+			$this->connection->getInner()->createSchemaManager()->dropTable($this->tableName);
+		}
 		parent::tearDown();
 	}