{"id":279,"date":"2014-06-18T14:19:18","date_gmt":"2014-06-18T14:19:18","guid":{"rendered":"http:\/\/tomas.papp.me.uk\/?p=279"},"modified":"2014-06-18T14:19:18","modified_gmt":"2014-06-18T14:19:18","slug":"alter-session-priamo-v-query-platny-len-do-dobehnutia-danej-query","status":"publish","type":"post","link":"https:\/\/tomas.papp.me.uk\/?p=279","title":{"rendered":"alter session priamo v query, platny len do dobehnutia danej query"},"content":{"rendered":"<p>Od Oracle 11g existuje sql hint OPT_PARAM ktorym sa da ohintovat SQL prikaz, funguje podobne ako alter session s tym ze je platny len do dobehnutia danej query<\/p>\n<p>&nbsp;<\/p>\n<pre>\/*+ opt_param(&lt;parameter_name&gt; [,] &lt;parameter_value&gt;) *\/<\/pre>\n<pre>parameter_name is the name of a parameter\r\n parameter_value is its value.<\/pre>\n<p>napriklad<\/p>\n<p>&nbsp;<\/p>\n<pre>select \/*+ opt_param('hash_join_enabled','false') *\/ \r\ndept_no,\r\nemp_name,\r\nempno \r\nfrom \r\nemp e, dept d \r\nwhere e.ename=d.dname;<\/pre>\n<pre><\/pre>\n<pre>select \/*+ opt_param('hash_join_enabled','false') *\/ \r\ndept_no,\r\nemp_name,\r\nempno \r\nfrom \r\nemp e, dept d \r\nwhere e.ename=d.dname;<\/pre>\n<p>&nbsp;<\/p>\n<p>alebo ak chceme pouzit viac<\/p>\n<p>&nbsp;<\/p>\n<pre>\/*+ OPT_PARAM('_always_semi_join' 'off')\r\n OPT_PARAM('_b_tree_bitmap_plans' 'false')\r\n OPT_PARAM('query_rewrite_enabled' 'false')\r\n OPT_PARAM('_new_initial_join_orders' 'false')\r\n OPT_PARAM('optimizer_dynamic_sampling' 1)\r\n OPT_PARAM('optimizer_index_cost_adj' 1) *\/<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Od Oracle 11g existuje sql hint OPT_PARAM ktorym sa da ohintovat SQL prikaz, funguje podobne ako alter session s tym ze je platny len do dobehnutia danej query &nbsp; \/*+ opt_param(&lt;parameter_name&gt; [,] &lt;parameter_value&gt;) *\/ parameter_name is the name of a parameter parameter_value is its value. napriklad &nbsp; select \/*+ opt_param(&#8216;hash_join_enabled&#8217;,&#8217;false&#8217;) *\/ dept_no, emp_name, empno from [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-279","post","type-post","status-publish","format-standard","hentry","category-oracle"],"_links":{"self":[{"href":"https:\/\/tomas.papp.me.uk\/index.php?rest_route=\/wp\/v2\/posts\/279","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tomas.papp.me.uk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tomas.papp.me.uk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tomas.papp.me.uk\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/tomas.papp.me.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=279"}],"version-history":[{"count":3,"href":"https:\/\/tomas.papp.me.uk\/index.php?rest_route=\/wp\/v2\/posts\/279\/revisions"}],"predecessor-version":[{"id":282,"href":"https:\/\/tomas.papp.me.uk\/index.php?rest_route=\/wp\/v2\/posts\/279\/revisions\/282"}],"wp:attachment":[{"href":"https:\/\/tomas.papp.me.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=279"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tomas.papp.me.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=279"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tomas.papp.me.uk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=279"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}