<!-- 
RSS generated by JIRA (9.7.1#970001-sha1:2222b88b221c4928ef0de3161136cc90c8356a66) at Thu Feb 08 05:53:39 UTC 2024

It is possible to restrict the fields that are returned in this document by specifying the 'field' parameter in your request.
For example, to request only the issue key and summary append 'field=key&field=summary' to the URL of your request.
-->
<rss version="0.92" >
<channel>
    <title>MongoDB Jira</title>
    <link>https://jira.mongodb.org</link>
    <description>This file is an XML representation of an issue</description>
    <language>en-us</language>    <build-info>
        <version>9.7.1</version>
        <build-number>970001</build-number>
        <build-date>13-04-2023</build-date>
    </build-info>


<item>
            <title>[SERVER-61915] Provide the ability for queries to &quot;hint&quot; and use a particular Query Engine</title>
                <link>https://jira.mongodb.org/browse/SERVER-61915</link>
                <project id="10000" key="SERVER">Core Server</project>
                    <description>&lt;p&gt;MongoDB version 5.X+ introduced the new Slot Based Execution (SBE) query engine. At the same time, the Classic Query Engine is available as well. This is a feature request to introduce a functionality that will allow users to &quot;hint&quot; and use a particular Query Engine while running a query. The benefits of this will be:&lt;/p&gt;
&lt;ul&gt;
	&lt;li&gt;It will provide the ability to compare/investigate the performance difference for queries while using either query engine, in &lt;em&gt;real-time&lt;/em&gt;.&lt;/li&gt;
	&lt;li&gt;It would make it unnecessary to &quot;switch&quot; the entire query engine (by&#160;enabling/disabling SBE) for &lt;em&gt;all&lt;/em&gt; the queries, just to compare/investigate the query performance difference with the 2 engines for a small subset of queries.&lt;/li&gt;
&lt;/ul&gt;
</description>
                <environment></environment>
        <key id="1942455">SERVER-61915</key>
            <summary>Provide the ability for queries to &quot;hint&quot; and use a particular Query Engine</summary>
                <type id="4" iconUrl="https://jira.mongodb.org/secure/viewavatar?size=xsmall&amp;avatarId=14710&amp;avatarType=issuetype">Improvement</type>
                                            <priority id="3" iconUrl="https://jira.mongodb.org/images/icons/priorities/major.svg">Major - P3</priority>
                        <status id="1" iconUrl="https://jira.mongodb.org/images/icons/statuses/open.png" description="">Open</status>
                    <statusCategory id="2" key="new" colorName="default"/>
                                    <resolution id="-1">Unresolved</resolution>
                                        <assignee username="backlog-query-optimization">Backlog - Query Optimization</assignee>
                                    <reporter username="harshad.dhavale@mongodb.com">Harshad Dhavale</reporter>
                        <labels>
                            <label>sbe</label>
                    </labels>
                <created>Fri, 3 Dec 2021 21:42:22 +0000</created>
                <updated>Tue, 30 Jan 2024 15:21:24 +0000</updated>
                                                                                                <votes>2</votes>
                                    <watches>18</watches>
                                                                                                                <comments>
                            <comment id="5888262" author="jussi@vainu.io" created="Fri, 17 Nov 2023 14:47:17 +0000"  >&lt;p&gt;We also have major issues with query plans with SBE and 7 (have to make another issue about them). Now it looks like we will have to start an annoying project to downgrade back to mongo 6 because of these issues.&#160;&lt;/p&gt;

&lt;p&gt;Upvoting this heavily.&#160;&lt;/p&gt;</comment>
                            <comment id="5855824" author="JIRAUSER1254095" created="Mon, 6 Nov 2023 05:25:32 +0000"  >&lt;p&gt;It&apos;s unfortunate that this ticket has sat unaddressed since 5.x. We had major issues with the SBE in 7.0 (&lt;a href=&quot;https://jira.mongodb.org/browse/SERVER-79088&quot; title=&quot;Improve SBE multi-planner performance for query which returns zero results&quot; class=&quot;issue-link&quot; data-issue-key=&quot;SERVER-79088&quot;&gt;&lt;del&gt;SERVER-79088&lt;/del&gt;&lt;/a&gt;, &lt;a href=&quot;https://jira.mongodb.org/browse/SERVER-82548&quot; title=&quot;MongoDB 7.0.2 SBE selects a different index when doing $in with a large array&quot; class=&quot;issue-link&quot; data-issue-key=&quot;SERVER-82548&quot;&gt;&lt;del&gt;SERVER-82548&lt;/del&gt;&lt;/a&gt;, &lt;a href=&quot;https://jira.mongodb.org/browse/SERVER-82549&quot; title=&quot;MongoDB 7.0.2 SBE query slow when direct index exists&quot; class=&quot;issue-link&quot; data-issue-key=&quot;SERVER-82549&quot;&gt;&lt;del&gt;SERVER-82549&lt;/del&gt;&lt;/a&gt;) that could have been mitigated if we had a way to opt-in/opt-out of the SBE gradually. I humbly suggest MongoDB to address this before more folks start upgrading to 7.0.&lt;/p&gt;

&lt;p&gt;For reference, it could be somewhere else besides the &quot;hint&quot; API, for example, it could be something similar to writeConcern.&lt;/p&gt;</comment>
                            <comment id="4234780" author="david.storch" created="Tue, 7 Dec 2021 16:20:45 +0000"  >&lt;p&gt;As part of the development of the new query optimizer, we are expecting to make some changes to the user-facing hint API. When doing so, we can consider in tandem whether or not to schedule this improvement.&lt;/p&gt;

&lt;p&gt;Note that a per-query hint to force the classic engine would need to be excluded from the stable API version 1. Also, since we eventually plan to remove support for the classic engine entirely at some point in the medium to long term future, we would need to clearly communicate to customers that this hint is a temporary solution; it will not be supported indefinitely, and a future release would drop support for this hint when the classic engine is removed.&lt;/p&gt;</comment>
                    </comments>
                <issuelinks>
                            <issuelinktype id="10011">
                    <name>Depends</name>
                                            <outwardlinks description="depends on">
                                        <issuelink>
            <issuekey id="2350195">SERVER-77469</issuekey>
        </issuelink>
                            </outwardlinks>
                                                        </issuelinktype>
                            <issuelinktype id="10010">
                    <name>Duplicate</name>
                                            <outwardlinks description="duplicates">
                                        <issuelink>
            <issuekey id="2485042">SERVER-82547</issuekey>
        </issuelink>
                            </outwardlinks>
                                                        </issuelinktype>
                            <issuelinktype id="10012">
                    <name>Related</name>
                                                                <inwardlinks description="is related to">
                                        <issuelink>
            <issuekey id="2485809">SERVER-82591</issuekey>
        </issuelink>
                            </inwardlinks>
                                    </issuelinktype>
                    </issuelinks>
                <attachments>
                    </attachments>
                <subtasks>
                    </subtasks>
                <customfields>
                                                <customfield id="customfield_10050" key="com.atlassian.jira.toolkit:comments">
                        <customfieldname># Replies</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>3.0</customfieldvalue>
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                <customfield id="customfield_12751" key="com.atlassian.jira.plugin.system.customfieldtypes:multiselect">
                        <customfieldname>Assigned Teams</customfieldname>
                        <customfieldvalues>
                                <customfieldvalue key="25126"><![CDATA[Query Optimization]]></customfieldvalue>
    
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    <customfield id="customfield_10055" key="com.atlassian.jira.ext.charting:firstresponsedate">
                        <customfieldname>Date of 1st Reply</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>Tue, 7 Dec 2021 16:20:45 +0000</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_10052" key="com.atlassian.jira.toolkit:dayslastcommented">
                        <customfieldname>Days since reply</customfieldname>
                        <customfieldvalues>
                                        11 weeks, 5 days ago
    
                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_18254" key="com.onresolve.jira.groovy.groovyrunner:scripted-field">
                        <customfieldname>Dependencies</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue><![CDATA[<a href='https://jira.mongodb.org/browse/PM-412'>PM-412</a>, <s><a href='https://jira.mongodb.org/browse/SERVER-77469'>SERVER-77469</a></s>]]></customfieldvalue>


                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_15850" key="com.atlassian.jira.plugins.jira-development-integration-plugin:devsummary">
                        <customfieldname>Development</customfieldname>
                        <customfieldvalues>
                            
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                            <customfield id="customfield_10857" key="com.pyxis.greenhopper.jira:gh-epic-link">
                        <customfieldname>Epic Link</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>PM-3574</customfieldvalue>
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                <customfield id="customfield_10057" key="com.atlassian.jira.toolkit:lastusercommented">
                        <customfieldname>Last comment by Customer</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>true</customfieldvalue>
                        </customfieldvalues>
                    </customfield>
                                                                                            <customfield id="customfield_10056" key="com.atlassian.jira.toolkit:lastupdaterorcommenter">
                        <customfieldname>Last commenter</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>ana.meza@mongodb.com</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_11151" key="com.atlassian.jira.toolkit:LastCommentDate">
                        <customfieldname>Last public comment date</customfieldname>
                        <customfieldvalues>
                            11 weeks, 5 days ago
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                    <customfield id="customfield_10051" key="com.atlassian.jira.toolkit:participants">
                        <customfieldname>Participants</customfieldname>
                        <customfieldvalues>
                                        <customfieldvalue>backlog-query-optimization</customfieldvalue>
            <customfieldvalue>david.storch@mongodb.com</customfieldvalue>
            <customfieldvalue>harshad.dhavale@mongodb.com</customfieldvalue>
            <customfieldvalue>shields@tablecheck.com</customfieldvalue>
            <customfieldvalue>jussi@vainu.io</customfieldvalue>
    
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                        <customfield id="customfield_14254" key="com.pyxis.greenhopper.jira:gh-lexo-rank">
                        <customfieldname>Product Rank</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>1|i0d7af:</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                <customfield id="customfield_12550" key="com.pyxis.greenhopper.jira:gh-lexo-rank">
                        <customfieldname>Rank</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>2|hr2amf:</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_10558" key="com.pyxis.greenhopper.jira:gh-global-rank">
                        <customfieldname>Rank (Obsolete)</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>9223372036854775807</customfieldvalue>
                        </customfieldvalues>
                    </customfield>
                                                                                            <customfield id="customfield_23361" key="com.onresolve.jira.groovy.groovyrunner:scripted-field">
                        <customfieldname>Requested By</customfieldname>
                        <customfieldvalues>
                                

                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    <customfield id="customfield_22870" key="com.onresolve.jira.groovy.groovyrunner:scripted-field">
                        <customfieldname>Triagers</customfieldname>
                        <customfieldvalues>
                                

                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                    <customfield id="customfield_14350" key="com.pyxis.greenhopper.jira:gh-lexo-rank">
                        <customfieldname>serverRank</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>1|i0ctfr:</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                    </customfields>
    </item>
</channel>
</rss>