diff --git a/lib/private/Authentication/TwoFactorAuth/Db/ProviderUserAssignmentDao.php b/lib/private/Authentication/TwoFactorAuth/Db/ProviderUserAssignmentDao.php
index 613185a2aec79..70a3827f301a1 100644
--- a/lib/private/Authentication/TwoFactorAuth/Db/ProviderUserAssignmentDao.php
+++ b/lib/private/Authentication/TwoFactorAuth/Db/ProviderUserAssignmentDao.php
@@ -89,13 +89,13 @@ public function deleteByUser(string $uid): array {
 			->where($qb2->expr()->eq('uid', $qb2->createNamedParameter($uid)));
 		$deleteQuery->executeStatement();
 
-		return array_values(array_map(function (array $row) {
+		return array_map(function (array $row) {
 			return [
 				'provider_id' => (string)$row['provider_id'],
 				'uid' => (string)$row['uid'],
 				'enabled' => ((int)$row['enabled']) === 1,
 			];
-		}, $rows));
+		}, $rows);
 	}
 
 	public function deleteAll(string $providerId): void {
diff --git a/lib/private/DB/ArrayResult.php b/lib/private/DB/ArrayResult.php
index 525b59e768d2b..614d4f77322ae 100644
--- a/lib/private/DB/ArrayResult.php
+++ b/lib/private/DB/ArrayResult.php
@@ -19,7 +19,7 @@ class ArrayResult implements IResult {
 	protected int $count;
 
 	public function __construct(
-		/** @var array<string, mixed> $rows */
+		/** @var list<array<string, mixed>> $rows */
 		protected array $rows,
 	) {
 		$this->count = count($this->rows);
@@ -66,52 +66,39 @@ public function fetchOne() {
 		$row = $this->fetch();
 		if ($row) {
 			return current($row);
-		} else {
-			return false;
 		}
+
+		return false;
 	}
 
 	#[Override]
 	public function fetchAssociative(): array|false {
 		$row = $this->fetch();
 		if ($row) {
-			/** @var array<string, mixed> $row */
 			return $row;
-		} else {
-			return false;
 		}
+
+		return false;
 	}
 
 	#[Override]
 	public function fetchNumeric(): array|false {
-		$row = $this->fetch(PDO::FETCH_NUM);
-		if ($row) {
-			/** @var list<mixed> $row */
-			return $row;
-		} else {
-			return false;
-		}
+		return $this->fetch(PDO::FETCH_NUM);
 	}
 
 	#[Override]
 	public function fetchAllNumeric(): array {
-		/** @var list<list<mixed>> $result */
-		$result = $this->fetchAll(PDO::FETCH_NUM);
-		return $result;
+		return $this->fetchAll(PDO::FETCH_NUM);
 	}
 
 	#[Override]
 	public function fetchAllAssociative(): array {
-		/** @var list<array<string,mixed>> $result */
-		$result = $this->fetchAll();
-		return $result;
+		return $this->fetchAll();
 	}
 
 	#[Override]
 	public function fetchFirstColumn(): array {
-		/** @var list<mixed> $result */
-		$result = $this->fetchAll(PDO::FETCH_COLUMN);
-		return $result;
+		return $this->fetchAll(PDO::FETCH_COLUMN);
 	}
 
 	#[Override]
diff --git a/lib/private/Files/Cache/QuerySearchHelper.php b/lib/private/Files/Cache/QuerySearchHelper.php
index 3ddcf1ca4e634..8cedfae597573 100644
--- a/lib/private/Files/Cache/QuerySearchHelper.php
+++ b/lib/private/Files/Cache/QuerySearchHelper.php
@@ -81,7 +81,7 @@ protected function applySearchConstraints(
 
 
 	/**
-	 * @return array<array-key, array{id: int, name: string, visibility: int, editable: int, ref_file_id: int, number_files: int}>
+	 * @return list<array{id: int, name: string, visibility: int, editable: int, ref_file_id: int, number_files: int}>
 	 */
 	public function findUsedTagsInCaches(ISearchQuery $searchQuery, array $caches): array {
 		$query = $this->getQueryBuilder();
@@ -90,6 +90,7 @@ public function findUsedTagsInCaches(ISearchQuery $searchQuery, array $caches):
 		$this->applySearchConstraints($query, $searchQuery, $caches);
 
 		$result = $query->executeQuery();
+		/** @var list<array{id: int, name: string, visibility: int, editable: int, ref_file_id: int, number_files: int}> $tags */
 		$tags = $result->fetchAll();
 		$result->closeCursor();
 		return $tags;
diff --git a/lib/public/DB/IResult.php b/lib/public/DB/IResult.php
index c3c4b37447060..4f7e048907c3f 100644
--- a/lib/public/DB/IResult.php
+++ b/lib/public/DB/IResult.php
@@ -39,9 +39,9 @@ interface IResult {
 	public function closeCursor(): bool;
 
 	/**
-	 * @param int $fetchMode
+	 * @param PDO::FETCH_* $fetchMode
 	 *
-	 * @return mixed
+	 * @return ($fetchMode is PDO::FETCH_ASSOC ? array<string, mixed> : ($fetchMode is PDO::FETCH_NUM ? list<mixed> : mixed))|false
 	 *
 	 * @since 21.0.0
 	 * @note Since 33.0.0, prefer using fetchAssociative/fetchNumeric/fetchOne or iterateAssociate/iterateNumeric instead.
@@ -76,9 +76,9 @@ public function fetchNumeric(): array|false;
 	public function fetchOne();
 
 	/**
-	 * @param int $fetchMode (one of PDO::FETCH_ASSOC, PDO::FETCH_NUM or PDO::FETCH_COLUMN (2, 3 or 7)
+	 * @param PDO::FETCH_* $fetchMode
 	 *
-	 * @return mixed[]
+	 * @return list<($fetchMode is PDO::FETCH_ASSOC ? array<string, mixed> : ($fetchMode is PDO::FETCH_NUM ? list<mixed> : mixed))>
 	 *
 	 * @since 21.0.0
 	 * @note Since 33.0.0, prefer using fetchAllAssociative/fetchAllNumeric/fetchFirstColumn or iterateAssociate/iterateNumeric instead.