From 14fe6b73933026825d36b6699f987150b6b33214 Mon Sep 17 00:00:00 2001 From: giveturtle Date: Fri, 26 Oct 2012 22:27:48 +1200 Subject: [PATCH] Added comment about $all's inefficiency See issue https://jira.mongodb.org/browse/SERVER-1000 --- source/reference/operator/all.txt | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/source/reference/operator/all.txt b/source/reference/operator/all.txt index d76b1366a5a..506f3312771 100644 --- a/source/reference/operator/all.txt +++ b/source/reference/operator/all.txt @@ -53,6 +53,13 @@ $all In most cases, MongoDB does not treat arrays as sets. This operator provides a notable exception to this approach. + + Currently, $all queries scan all the documents that match + the first element in the query array. This means that even with + when the field is indexed, queries may take a very long time + to return (especially when the first element in the array appears + in many documents). + See: https://jira.mongodb.org/browse/SERVER-1000 .. seealso:: :method:`find() `, :method:`update()