diff --git a/CHANGES.md b/CHANGES.md
index b94c3c4c..3ad10d51 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -5,6 +5,7 @@
 * Update CacheControl 0.13.1 (783a338) to 0.14.0 (e2be0c2)
 * Update certifi 2024.02.02 to 2024.06.02
 * Update dateutil 2.8.2 (296d419) to 2.9.0.post0 (0353b78)
+* Update diskcache 5.6.3 (323787f) to 5.6.3 (ebfa37c)
 * Update feedparser 6.0.10 (9865dec) to 6.0.11 (efcb89b)
 * Update filelock 3.12.4 (c1163ae) to 3.14.0 (8556141)
 * Update idna library 3.4 (cab054c) to 3.7 (1d365e1)
diff --git a/lib/diskcache/core.py b/lib/diskcache/core.py
index 46f5532b..461a4359 100644
--- a/lib/diskcache/core.py
+++ b/lib/diskcache/core.py
@@ -532,7 +532,7 @@ class Cache:
 
         sql(
             'CREATE INDEX IF NOT EXISTS Cache_expire_time ON'
-            ' Cache (expire_time)'
+            ' Cache (expire_time) WHERE expire_time IS NOT NULL'
         )
 
         query = EVICTION_POLICY[self.eviction_policy]['init']
@@ -2030,7 +2030,10 @@ class Cache:
 
         """
         sql = self._sql
-        sql('CREATE INDEX IF NOT EXISTS Cache_tag_rowid ON Cache(tag, rowid)')
+        sql(
+            'CREATE INDEX IF NOT EXISTS Cache_tag_rowid ON Cache(tag, rowid) '
+            'WHERE tag IS NOT NULL'
+        )
         self.reset('tag_index', 1)
 
     def drop_tag_index(self):