Update obsolete nbtree deletion comments.

_bt_delitems_delete() is no longer the high-level entry point used by
index tuple deletion driven by index tuples whose LP_DEAD bits are set
(now called "simple index tuple deletion").  It became a lower level
routine that's only called by _bt_delitems_delete_check() following
commit d168b66682.

diff --git a/src/backend/access/nbtree/nbtpage.c b/src/backend/access/nbtree/nbtpage.c
index ebec8fa5b896724ff7f3188b16653c0c8a90eb39..5bc7c3616a90a7be2f7dfea7f034ea225e0e075f 100644 (file)
--- a/src/backend/access/nbtree/nbtpage.c
+++ b/src/backend/access/nbtree/nbtpage.c
@@ -1197,7 +1197,7 @@ _bt_delitems_vacuum(Relation rel, Buffer buf,
     *
     * PageIndexTupleOverwrite() won't unset each item's LP_DEAD bit when it
     * happens to already be set.  It's important that we not interfere with
-    * _bt_delitems_delete().
+    * any future simple index tuple deletion operations.
     */
    for (int i = 0; i < nupdatable; i++)
    {
@@ -1230,7 +1230,7 @@ _bt_delitems_vacuum(Relation rel, Buffer buf,
     * This flag indicates the presence of LP_DEAD items on the page (though
     * not reliably).  Note that we only rely on it with pg_upgrade'd
     * !heapkeyspace indexes.  That's why clearing it here won't usually
-    * interfere with _bt_delitems_delete().
+    * interfere with simple index tuple deletion.
     */
    opaque->btpo_flags &= ~BTP_HAS_GARBAGE;