{"id":978,"date":"2017-03-04T03:29:49","date_gmt":"2017-03-03T21:59:49","guid":{"rendered":"http:\/\/pramodsingla.com\/?p=978"},"modified":"2017-03-04T03:29:49","modified_gmt":"2017-03-03T21:59:49","slug":"mssql-server-find-bad-indexes","status":"publish","type":"post","link":"https:\/\/pramodsingla.com\/?p=978","title":{"rendered":"MSSQL Server: Find Bad Indexes"},"content":{"rendered":"

Problem Statement: <\/strong>Script to find the Bad indexes
\nSolution: <\/strong>The indexes returned by the below query degrade the performance of the write queries. Consider deleting them.<\/h2>\n

–Find the bad indexes using following DMV:<\/span><\/i>
\n<\/span>— Possible Bad NC Indexes (writes > reads)<\/i><\/span>
\n<\/span>SELECT<\/span> <\/span>Object_name<\/i><\/span>(<\/span>s<\/span>.<\/span>[object_id]<\/span>)<\/span>                                <\/span>AS<\/span> <\/span>[Table Name]<\/span>
\n<\/span>,<\/span>
\n<\/span>i<\/span>.<\/span>NAME<\/span>                                                    <\/span>AS<\/span>
\n<\/span>[Index Name]<\/span>
\n<\/span>,<\/span>
\n<\/span>i<\/span>.<\/span>index_id<\/span>,<\/span>
\n<\/span>user_updates<\/span>                                              <\/span>AS<\/span>
\n<\/span>[Total Writes]<\/span>,<\/span>–number of updates by user queries<\/i><\/span>
\n<\/span>user_seeks<\/span> <\/span>+<\/span> <\/span>user_scans<\/span> <\/span>+<\/span> <\/span>user_lookups<\/span>                    <\/span>AS<\/span>
\n<\/span>[Total Reads]<\/span>,<\/span>
\n<\/span>user_updates<\/span> <\/span>–<\/span> <\/span>(<\/span> <\/span>user_seeks<\/span> <\/span>+<\/span> <\/span>user_scans<\/span> <\/span>+<\/span> <\/span>user_lookups<\/span> <\/span>)<\/span> <\/span>AS<\/span> <\/span>[Difference]<\/span>
\n<\/span>FROM<\/span>   <\/span>sys<\/span>.<\/span>dm_db_index_usage_stats<\/span> <\/span>AS<\/span> <\/span>s<\/span> <\/span>WITH<\/span> <\/span>(<\/span>NOLOCK<\/span>)<\/span>
\n<\/span>INNER<\/span> <\/span>JOIN<\/span> <\/span>sys<\/span>.<\/span>indexes<\/span> <\/span>AS<\/span> <\/span>i<\/span> <\/span>WITH<\/span> <\/span>(<\/span>NOLOCK<\/span>)<\/span>
\n<\/span>ON<\/span> <\/span>s<\/span>.<\/span>[object_id]<\/span> <\/span>=<\/span> <\/span>i<\/span>.<\/span>[object_id]<\/span>
\n<\/span>AND<\/span> <\/span>i<\/span>.<\/span>index_id<\/span> <\/span>=<\/span> <\/span>s<\/span>.<\/span>index_id<\/span>
\n<\/span>WHERE<\/span>  <\/span>OBJECTPROPERTY<\/b><\/span>(<\/span>s<\/span>.<\/span>[object_id]<\/span>,<\/span> <\/span>‘IsUserTable’<\/span>)<\/span> <\/span>=<\/span> <\/span>1<\/span>
\n<\/span>AND<\/span> <\/span>s<\/span>.<\/span>database_id<\/span> <\/span>=<\/span> <\/span>Db_id<\/i><\/span>(<\/span>)<\/span>
\n<\/span>AND<\/span> <\/span>user_updates<\/span> <\/span>><\/span> <\/span>(<\/span> <\/span>user_seeks<\/span> <\/span>+<\/span> <\/span>user_scans<\/span> <\/span>+<\/span> <\/span>user_lookups<\/span> <\/span>)<\/span>
\n<\/span>AND<\/span> <\/span>i<\/span>.<\/span>index_id<\/span> <\/span>><\/span> <\/span>1<\/span>
\n<\/span>ORDER<\/span>  <\/span>BY<\/span> <\/span>[Difference]<\/span> <\/span>DESC<\/span>,<\/span>
\n<\/span>[Total Writes]<\/span> <\/span>DESC<\/span>,<\/span>
\n<\/span>[Total Reads]<\/span> <\/span>ASC<\/span>
\n<\/span>OPTION<\/span> <\/span>(<\/span>RECOMPILE<\/span>)<\/span>;<\/span>  <\/span> <\/span><\/strong><\/p><\/blockquote>\n","protected":false},"excerpt":{"rendered":"

Problem Statement: Script to find the Bad indexes Solution: The indexes returned by the below query degrade the performance of the[…]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_mi_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0},"categories":[23,29],"tags":[55,86],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/pramodsingla.com\/index.php?rest_route=\/wp\/v2\/posts\/978"}],"collection":[{"href":"https:\/\/pramodsingla.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/pramodsingla.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/pramodsingla.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pramodsingla.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=978"}],"version-history":[{"count":0,"href":"https:\/\/pramodsingla.com\/index.php?rest_route=\/wp\/v2\/posts\/978\/revisions"}],"wp:attachment":[{"href":"https:\/\/pramodsingla.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=978"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/pramodsingla.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=978"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/pramodsingla.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=978"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}