From 77c5f5b336013a65e7ae46190ed4737f7a4b6f91 Mon Sep 17 00:00:00 2001 From: Jeff Allen Date: Fri, 8 Jan 2021 11:26:43 -0500 Subject: [PATCH] (DOCS-11033): Add limitation for 3.2 and earlier multikey indexes --- source/core/index-multikey.txt | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/source/core/index-multikey.txt b/source/core/index-multikey.txt index cbcce61869d..37e21debc21 100644 --- a/source/core/index-multikey.txt +++ b/source/core/index-multikey.txt @@ -210,6 +210,20 @@ $expr :query:`$expr` does not support multikey indexes. +Indexes Built on MongoDB 3.2 or Earlier +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Indexes built on MongoDB 3.2 or earlier do not contain the necessary +flags to support optimized multikey index use. To benefit from the +performance enhancements of multikey indexes, you must either: + +- Rebuild the older-format indexes on MongoDB 3.4 or later. See + :method:`db.collection.reIndex()`. + +- On a replica set, :doc:`resync the replica set members + ` containing older-format + indexes. + Examples --------