diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index c49f1624b4c..a580a3c4924 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -2052,11 +2052,18 @@ do_autovacuum(void)
 		if (classForm->relpersistence == RELPERSISTENCE_TEMP)
 		{
 			int			backendID;
+			PGPROC	   *proc;
 
 			backendID = GetTempNamespaceBackendId(classForm->relnamespace);
 
-			/* We just ignore it if the owning backend is still active */
-			if (backendID == MyBackendId || BackendIdGetProc(backendID) == NULL)
+			/*
+			 * We just ignore it if the owning backend is still active in the
+			 * same database.
+			 */
+			if (backendID != InvalidBackendId &&
+				(backendID == MyBackendId ||
+				 (proc = BackendIdGetProc(backendID)) == NULL ||
+				 proc->databaseId != MyDatabaseId))
 			{
 				/*
 				 * We found an orphan temp table (which was probably left