SharePoint 2010/2013: List view Lookup threshold uncovered

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SharePoint with Large lists is common scenario in any Sharepoint deployment. While there are Several blogs / Guidance TechNet articles which exist working /Managing Large lists, My blog is particularly about the "List view lookup Threshold"

Here is a table summarizes information about resource throttles and limits that you need to be aware of. These throttles and limits are set on the Resource Throttling page in Central Administration

From <http://office.microsoft.com/en-in/sharepoint-server-help/manage-lists-and-libraries-with-many-items-HA102771361.aspx>

This feature limits the number of joins that a query can perform. Each lookup column in a list view causes a join with another table. Each additional lookup column in a view increases the complexity of metadata navigation and list view queries. By number of joins, I mean the number of Lookup, Person/Group, or Workflow Status fields that are included in the query. So for example, if you have a view that displays 6 lookup columns, and filters on another 3 distinct lookup columns then by default that view won‘t work, since the List View Lookup Threshold is 8, and the view is attempting to use 9 lookups.

Here are few observations which affect this threshold , which may cause either the request to hit the threshold limit & hence be throttled or may lead to the views showing data beyond the threshold limit configured in central Admin

1. What classifies as Lookup columns: Standard lookup columns, single-value managed metadata, multiple-value managed metadata, single-value people and group columns, and multiple-value people and group columns , Workflow Status , Created by , Modified by ( people ) are obviously counted as lookup columns .

2. Additionally following columns shows on list view also work as lookup columns , Name ( linked to Document) , Link (Edit to edit item) , Name ( linked to Document with edit menu), type ( icon linked to document)

3. We allow overriding the query throttling in following circumstances

a. User is browsing when the system is in an Unthrottled Time window ( Web application throttling settings)

b. The current user is a box administrator (part of local admin group on the machine where the request is served from) . Local admin privileges can also be obtained by being part of an AD group which in turn is a part of local or Domain Admins groups . you can use the following command prompt to dump the group membership of a logged on user on a particular Machine /workstation .

C:> WhoAmI /Groups

c. The user is browsing using farm admin/Application Pool account   for the Web-application .

We highly recommend that you do not increase this number beyond the Default Threshold Limit , because through thorough testing we‘ve observed that there‘s a serious non-gradual performance degradation that shows up above 8/12  joins. Not only does the throughput that the server can handle drop significantly at that point, but the query ends up using a disproportionately large amount of the SQL Server‘s resources, which negatively affects everybody else using that same database. Here is an article which talks about more on the Performance impact http://technet.microsoft.com/en-us/library/ff608068(office.14).aspx

References:

Working with Large Lists in SharePoint 2010 - List Throttling

SharePoint 2010: How to Change the List View Threshold and Other Resource Throttling Settings

Manage lists and libraries with many items

** Note : The List view Lookup Threshold has been revised to Default of 12 in SharePoint 2013 , after applying  the June 2013 CU update . http://support.microsoft.com/kb/2817414

Any new Web-Application created will have List View Lookup Threshold set to  Default =12 , While the values on Existing Web-apps needs to be modified Manually . 

From: https://blogs.msdn.microsoft.com/spses/2013/12/02/sharepoint-20102013-list-view-lookup-threshold-uncovered/

SharePoint 2010/2013: List view Lookup threshold uncovered

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原文地址：https://www.cnblogs.com/time-is-life/p/8805835.html