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-rw-r--r--src/backend/access/gist/README8
1 files changed, 4 insertions, 4 deletions
diff --git a/src/backend/access/gist/README b/src/backend/access/gist/README
index efb2730e181..8015ff19f05 100644
--- a/src/backend/access/gist/README
+++ b/src/backend/access/gist/README
@@ -271,10 +271,10 @@ should be visited too. When split inserts the downlink to the parent, it
clears the F_FOLLOW_RIGHT flag in the child, and sets the NSN field in the
child page header to match the LSN of the insertion on the parent. If the
F_FOLLOW_RIGHT flag is not set, a scan compares the NSN on the child and the
-LSN it saw in the parent. If NSN < LSN, the scan looked at the parent page
-before the downlink was inserted, so it should follow the rightlink. Otherwise
-the scan saw the downlink in the parent page, and will/did follow that as
-usual.
+LSN it saw in the parent. If the child's NSN is greater than the LSN seen on
+the parent, the scan looked at the parent page before the downlink was
+inserted, so it should follow the rightlink. Otherwise the scan saw the
+downlink in the parent page, and will/did follow that as usual.
A scan can't normally see a page with the F_FOLLOW_RIGHT flag set, because
a page split keeps the child pages locked until the downlink has been inserted