{"id":2136,"date":"2012-05-14T09:24:06","date_gmt":"2012-05-14T09:24:06","guid":{"rendered":"http:\/\/enjoyasp.net\/?p=2136"},"modified":"2012-05-14T09:40:41","modified_gmt":"2012-05-14T09:40:41","slug":"%e7%b4%a2%e5%bc%95%e5%a4%b1%e6%95%88","status":"publish","type":"post","link":"https:\/\/enjoyasp.net\/index.php\/2012\/05\/14\/%e7%b4%a2%e5%bc%95%e5%a4%b1%e6%95%88\/","title":{"rendered":"\u7edf\u8ba1\u4fe1\u606f"},"content":{"rendered":"

\u636e\u7edf\u8ba1\u4fe1\u606f\u6765\u4f5c\u9884\u4f30\uff0c\u5982\u6267\u884c\u8ba1\u7b97\u9884\u4f30\u7684\u8fd4\u56de\u884c
\n\u67e5\u770b\u7edf\u8ba1\u4fe1\u606f\uff1aDBCC SHOW_STATISTICS ('bdship','IX_bdship_2')
\n\u5efa\u7acb\u7d22\u5f15\u540e\uff0c\u82e5\u60f3\u770b\u5176\u597d\u574f\uff0c\u7528DBCC SHOW_STATISTICS ('bdship','IX_bdship_2')\u67e5\u770b\u91cd\u590d\u7387\uff0c\u8d8a\u5c0f\u8d8a\u597d\u3002
\n\u7edf\u8ba1\u4fe1\u606f\u7ef4\u62a4\uff1a
\n    1\uff0c\u8868\u683c\u4ece\u6ca1\u6709\u6570\u636e\u53d8\u6210\u6709\u6570\u636e\u65f6\uff0c\u5982\u7d22\u5f15\u91cd\u5efa\u3002
\n    2\uff0c\u5c0f\u8868\uff08500\u884c\u4ee5\u4e0b\u6570\u636e\uff09\uff0c\u5f53\u7edf\u8ba1\u4fe1\u606f\u7b2c\u4e00\u4e2a\u5b57\u6bb5\u7d2f\u8ba1\u53d8\u5316\u5927\u4e8e500\u4ee5\u540e
\n    3\uff0c\u5927\u8868\uff08500\u884c\u4ee5\u4e0a\uff09\uff0c\u5f53\u7edf\u8ba1\u4fe1\u606f\u7b2c\u4e00\u4e2a\u5b57\u6bb5\u7d2f\u8ba1\u53d8\u5316\u5927\u4e8e500+\uff0820%*\u8868\u683c\u6570\u636e\u603b\u91cf\uff09\u65f6\uff0c\u5373\u5728\u8868\u4e94\u5206\u4e4b\u4e00\u4ee5\u4e0a\u7684\u6570\u636e\u53d1\u751f\u53d8\u5316\u65f6\uff0c\u4f1a\u81ea\u52a8\u66f4\u65b0\u7edf\u8ba1\u4fe1\u606f\u3002
\n    4\uff0c\u624b\u5de5\u66f4\u65b0\uff0c\u5982\u4e0b\uff1a
\n\u624b\u5de5\u66f4\u65b0\u7edf\u8ba1\u4fe1\u606f\uff1a
\nUPDATE STATISTICS  mdDept –\u8868
\nUPDATE STATISTICS  mdDept IX_mdDept –\u8868\u4e0a\u7d22\u5f15<\/p>\n

\n1,\u7d22\u5f15\u8981\u5efa\u7acb\u5728\u91cd\u590d\u5c11\u7684\u5b57\u6bb5\u4e0a\u624d\u6709\u610f\u4e49\uff0c\u8bd5\u60f3\u82e5\u5b57\u6bb5\u5168\u76f8\u540c\uff0c\u90a3\u505a\u7d22\u5f15\u5c31\u6ca1\u6709\u610f\u4e49\u3002
\n\u7d22\u5f15\u5efa\u7acb\u540e\u53ef\u901a\u8fc7DBCC SHOW_STATISTICS ('bdship','IX_bdship_2')\u6765\u5224\u65ad\uff0c
\n\u7b2c\u4e00\u4e2a\u8868\u7684Density
\n\u82e5Density\u63a5\u8fd1\u4e8e1\uff0c\u8bf4\u660e\u91cd\u590d\u7387\u975e\u5e38\u5c0f\uff0c\u7d22\u5f15\u5efa\u7acb\u7684\u5f88\u597d
\n\u82e5Density\u5c0f\u4e8e0.1\uff0c\u8bf4\u660e\u91cd\u590d\u5f88\u5927\uff0c\u5efa\u4e0d\u5efa\u7acb\u7d22\u5f15\u5f71\u54cd\u4e0d\u5927\uff0c\u67d0\u4e9b\u65f6\u5019\u4f1a\u7528\u626b\u63cf\u65b9\u5f0f\u66ff\u4ee3\u7d22\u5f15\u67e5\u627e<\/p>\n

\u7b2c\u4e09\u4e2a\u8868\uff1a
\nRANGE_HI_KEY:
\n\u6bcf\u7ec4\u6570\u636e\u7684\u6700\u5927\u503c
\nRANGE_ROWS:\u6bcf\u7ec4\u6570\u636e\u533a\u95f4\u884c\u6570\uff0c\u4e0d\u542b\u6700\u5927\u503c\u3002\u5373\uff1a(\u4e0a\u4e00\u884c\u503c\uff0c\u5f53\u524d\u884c\u503c)
\nEQ_ROWS\uff1a\u7b49\u4e8eRANGE_HI_KEY\u7684\u503c\u7684\u6570\u91cf
\nDISTINCT_RANGE_ROWS:\u6bcf\u7ec4\u6570\u636e\u975e\u91cd\u590d\u6570\u91cf
\nAVG_RANGE_ROWS:\u91cd\u590d\u503c\u7684\u5e73\u5747\u6570\u91cf,\u4e0d\u542b\u4e0a\u9650\u503c
\n=RANGE_ROWS\/DISTINCT_RANGE_ROWS
\n\u8fd9\u6837\uff0c\u901a\u8fc7\u7ed9\u5b9a\u7684\u4e00\u4e2a\u6761\u4ef6\uff0c\u5c31\u80fd\u9884\u4f30\u5927\u6982\u6709\u591a\u5c11\u884c\u6570\u636e\uff0c\u6709\u591a\u5c11M\u6570\u636e\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"

\u636e\u7edf\u8ba1\u4fe1\u606f\u6765\u4f5c\u9884\u4f30\uff0c\u5982\u6267\u884c\u8ba1\u7b97\u9884\u4f30\u7684\u8fd4\u56de\u884c \u67e5\u770b\u7edf\u8ba1\u4fe1\u606f\uff1aDBCC SHOW_STATISTICS (&#39 […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[36],"tags":[],"class_list":["post-2136","post","type-post","status-publish","format-standard","hentry","category-sql-server"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/posts\/2136","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/comments?post=2136"}],"version-history":[{"count":0,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/posts\/2136\/revisions"}],"wp:attachment":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/media?parent=2136"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/categories?post=2136"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/tags?post=2136"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}