{"id":694,"date":"2015-02-28T15:01:09","date_gmt":"2015-02-28T15:01:09","guid":{"rendered":"http:\/\/dotnetsql.info\/net-sql\/?p=694"},"modified":"2015-08-14T12:10:20","modified_gmt":"2015-08-14T11:10:20","slug":"what-is-blocking","status":"publish","type":"post","link":"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/","title":{"rendered":"#SqlServer interview question: What is blocking?"},"content":{"rendered":"<p>SQL Server blocking occurs when one connection places a lock on a table (or selected rows, pages, extent) and another connection attempts to read or modify the data when the lock is in effect. <!--more-->Another connection has to wait until the resources are released from the original connection which is holding the lock on the resources. Blocking often happens on the server when the system is under heavy transactional workload on a single resource.<\/p>\n<p>The way to resolve blocking is to identify the blocking statements which will then allow optimization of the blocking statements (re-write T-SQL, Indexing, or other configuration changes).<\/p>\n<p><strong>Thanks for reading this article,<\/strong><\/p>\n<p><strong>Next steps :<\/strong><\/p>\n<p style=\"margin-left: 18pt;\"><strong>1. \u00a0<\/strong><strong>Share this with your colleagues because Sharing\u00a0 is Learning<\/strong><\/p>\n<p><strong>\u00a0 \u00a0 \u00a0 \u00a02. \u00a0Comment below if you need any assistance<\/strong><\/p>\n<p style=\"text-align: right;\"><em><strong>Powered by <a href=\"http:\/\/www.codereview.co\">CodeReview &#8211; Let&#8217;s make it Better!<\/a><\/strong><\/em><\/p>\n<div class=\"sharedaddy sd-sharing-enabled\"><div class=\"robots-nocontent sd-block sd-social sd-social-icon sd-sharing\"><h3 class=\"sd-title\">Share this:<\/h3><div class=\"sd-content\"><ul><li class=\"share-twitter\"><a rel=\"nofollow\" data-shared=\"sharing-twitter-694\" class=\"share-twitter sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=twitter\" target=\"_blank\" title=\"Click to share on Twitter\"><span><\/span><span class=\"sharing-screen-reader-text\">Click to share on Twitter (Opens in new window)<\/span><\/a><\/li><li class=\"share-linkedin\"><a rel=\"nofollow\" data-shared=\"sharing-linkedin-694\" class=\"share-linkedin sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=linkedin\" target=\"_blank\" title=\"Click to share on LinkedIn\"><span><\/span><span class=\"sharing-screen-reader-text\">Click to share on LinkedIn (Opens in new window)<\/span><\/a><\/li><li class=\"share-facebook\"><a rel=\"nofollow\" data-shared=\"sharing-facebook-694\" class=\"share-facebook sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=facebook\" target=\"_blank\" title=\"Share on Facebook\"><span><\/span><span class=\"sharing-screen-reader-text\">Share on Facebook (Opens in new window)<\/span><\/a><\/li><li class=\"share-google-plus-1\"><a rel=\"nofollow\" data-shared=\"sharing-google-694\" class=\"share-google-plus-1 sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=google-plus-1\" target=\"_blank\" title=\"Click to share on Google+\"><span><\/span><span class=\"sharing-screen-reader-text\">Click to share on Google+ (Opens in new window)<\/span><\/a><\/li><li class=\"share-pocket\"><a rel=\"nofollow\" data-shared=\"\" class=\"share-pocket sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=pocket\" target=\"_blank\" title=\"Click to share on Pocket\"><span><\/span><span class=\"sharing-screen-reader-text\">Click to share on Pocket (Opens in new window)<\/span><\/a><\/li><li class=\"share-email\"><a rel=\"nofollow\" data-shared=\"\" class=\"share-email sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=email\" target=\"_blank\" title=\"Click to email this to a friend\"><span><\/span><span class=\"sharing-screen-reader-text\">Click to email this to a friend (Opens in new window)<\/span><\/a><\/li><li class=\"share-end\"><\/li><\/ul><\/div><\/div><\/div><div class='sharedaddy sd-block sd-like jetpack-likes-widget-wrapper jetpack-likes-widget-unloaded' id='like-post-wrapper-76243027-694-69e23100736af' data-src='\/\/widgets.wp.com\/likes\/#blog_id=76243027&amp;post_id=694&amp;origin=dotnetsql.info&amp;obj_id=76243027-694-69e23100736af' data-name='like-post-frame-76243027-694-69e23100736af'><h3 class='sd-title'>Like this:<\/h3><div class='likes-widget-placeholder post-likes-widget-placeholder' style='height:55px'><span class='button'><span>Like<\/span><\/span> <span class=\"loading\">Loading...<\/span><\/div><span class='sd-text-color'><\/span><a class='sd-link-color'><\/a><\/div>","protected":false},"excerpt":{"rendered":"<p>SQL Server blocking occurs when one connection places a lock on a table (or selected rows, pages, extent) and another connection attempts to read or modify the data when the lock is in effect.<\/p>\n<div class=\"sharedaddy sd-sharing-enabled\"><div class=\"robots-nocontent sd-block sd-social sd-social-icon sd-sharing\"><h3 class=\"sd-title\">Share this:<\/h3><div class=\"sd-content\"><ul><li class=\"share-twitter\"><a rel=\"nofollow\" data-shared=\"sharing-twitter-694\" class=\"share-twitter sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=twitter\" target=\"_blank\" title=\"Click to share on Twitter\"><span><\/span><span class=\"sharing-screen-reader-text\">Click to share on Twitter (Opens in new window)<\/span><\/a><\/li><li class=\"share-linkedin\"><a rel=\"nofollow\" data-shared=\"sharing-linkedin-694\" class=\"share-linkedin sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=linkedin\" target=\"_blank\" title=\"Click to share on LinkedIn\"><span><\/span><span class=\"sharing-screen-reader-text\">Click to share on LinkedIn (Opens in new window)<\/span><\/a><\/li><li class=\"share-facebook\"><a rel=\"nofollow\" data-shared=\"sharing-facebook-694\" class=\"share-facebook sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=facebook\" target=\"_blank\" title=\"Share on Facebook\"><span><\/span><span class=\"sharing-screen-reader-text\">Share on Facebook (Opens in new window)<\/span><\/a><\/li><li class=\"share-google-plus-1\"><a rel=\"nofollow\" data-shared=\"sharing-google-694\" class=\"share-google-plus-1 sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=google-plus-1\" target=\"_blank\" title=\"Click to share on Google+\"><span><\/span><span class=\"sharing-screen-reader-text\">Click to share on Google+ (Opens in new window)<\/span><\/a><\/li><li class=\"share-pocket\"><a rel=\"nofollow\" data-shared=\"\" class=\"share-pocket sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=pocket\" target=\"_blank\" title=\"Click to share on Pocket\"><span><\/span><span class=\"sharing-screen-reader-text\">Click to share on Pocket (Opens in new window)<\/span><\/a><\/li><li class=\"share-email\"><a rel=\"nofollow\" data-shared=\"\" class=\"share-email sd-button share-icon no-text\" href=\"http:\/\/dotnetsql.info\/net-sql\/index.php\/what-is-blocking\/?share=email\" target=\"_blank\" title=\"Click to email this to a friend\"><span><\/span><span class=\"sharing-screen-reader-text\">Click to email this to a friend (Opens in new window)<\/span><\/a><\/li><li class=\"share-end\"><\/li><\/ul><\/div><\/div><\/div><div class='sharedaddy sd-block sd-like jetpack-likes-widget-wrapper jetpack-likes-widget-unloaded' id='like-post-wrapper-76243027-694-69e2310073b9a' data-src='\/\/widgets.wp.com\/likes\/#blog_id=76243027&amp;post_id=694&amp;origin=dotnetsql.info&amp;obj_id=76243027-694-69e2310073b9a' data-name='like-post-frame-76243027-694-69e2310073b9a'><h3 class='sd-title'>Like this:<\/h3><div class='likes-widget-placeholder post-likes-widget-placeholder' style='height:55px'><span class='button'><span>Like<\/span><\/span> <span class=\"loading\">Loading...<\/span><\/div><span class='sd-text-color'><\/span><a class='sd-link-color'><\/a><\/div>","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[303,25],"tags":[128,97,40],"aioseo_notices":[],"_links":{"self":[{"href":"http:\/\/dotnetsql.info\/net-sql\/index.php\/wp-json\/wp\/v2\/posts\/694"}],"collection":[{"href":"http:\/\/dotnetsql.info\/net-sql\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/dotnetsql.info\/net-sql\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/dotnetsql.info\/net-sql\/index.php\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"http:\/\/dotnetsql.info\/net-sql\/index.php\/wp-json\/wp\/v2\/comments?post=694"}],"version-history":[{"count":6,"href":"http:\/\/dotnetsql.info\/net-sql\/index.php\/wp-json\/wp\/v2\/posts\/694\/revisions"}],"predecessor-version":[{"id":1142,"href":"http:\/\/dotnetsql.info\/net-sql\/index.php\/wp-json\/wp\/v2\/posts\/694\/revisions\/1142"}],"wp:attachment":[{"href":"http:\/\/dotnetsql.info\/net-sql\/index.php\/wp-json\/wp\/v2\/media?parent=694"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/dotnetsql.info\/net-sql\/index.php\/wp-json\/wp\/v2\/categories?post=694"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/dotnetsql.info\/net-sql\/index.php\/wp-json\/wp\/v2\/tags?post=694"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}