{"id":1491,"date":"2019-05-08T10:51:53","date_gmt":"2019-05-08T02:51:53","guid":{"rendered":"http:\/\/www.llku.com\/?p=1491"},"modified":"2019-05-08T15:00:20","modified_gmt":"2019-05-08T07:00:20","slug":"oracle-db-scn%e6%83%85%e5%86%b5%e6%9f%a5%e8%af%a2","status":"publish","type":"post","link":"https:\/\/www.llku.com\/?p=1491","title":{"rendered":"Oracle DB scn\u60c5\u51b5\u67e5\u8be2"},"content":{"rendered":"

\n\t–1\u3001\u67e5\u8be2\u5f53\u524dscn\u60c5\u51b5\n<\/p>\n

\n\tselect version,
\n\t       date_time,
\n\t       dbms_flashback.get_system_change_number current_scn,
\n\t       indicator
\n\t  from (select version,
\n\t               to_char(SYSDATE, 'YYYY\/MM\/DD HH24:MI:SS') DATE_TIME,
\n\t               ((((((to_number(to_char(sysdate, 'YYYY')) – 1988) * 12 * 31 * 24 * 60 * 60) +
\n\t               ((to_number(to_char(sysdate, 'MM')) – 1) * 31 * 24 * 60 * 60) +
\n\t               (((to_number(to_char(sysdate, 'DD')) – 1)) * 24 * 60 * 60) +
\n\t               (to_number(to_char(sysdate, 'HH24')) * 60 * 60) +
\n\t               (to_number(to_char(sysdate, 'MI')) * 60) +
\n\t               (to_number(to_char(sysdate, 'SS')))) * (16 * 1024)) –
\n\t               SYS.dbms_flashback.get_system_change_number) \/
\n\t               (16 * 1024 * 60 * 60 * 24)) indicator
\n\t          from v$instance);\n<\/p>\n

\n\t–2\u3001\u67e5\u8be2\u8ddd\u79bb\u4e0a\u9650\u5929\u6570\u7684\u5386\u53f2\u53d8\u5316\u60c5\u51b5\n<\/p>\n

\n\tSELECT tim,
\n\t       gscn,
\n\t       round(rate),
\n\t       round((chk16kscn – gscn) \/ 24 \/ 3600 \/ 16 \/ 1024, 1) "HEADROOM"
\n\t  FROM (SELECT tim,
\n\t               gscn,
\n\t               rate,
\n\t               ((((to_number(to_char(tim, 'YYYY')) – 1988) * 12 * 31 * 24 * 60 * 60) +
\n\t               ((to_number(to_char(tim, 'MM')) – 1) * 31 * 24 * 60 * 60) +
\n\t               (((to_number(to_char(tim, 'DD')) – 1)) * 24 * 60 * 60) +
\n\t               (to_number(to_char(tim, 'HH24')) * 60 * 60) +
\n\t               (to_number(to_char(tim, 'MI')) * 60) +
\n\t               (to_number(to_char(tim, 'SS')))) * (16 * 1024)) chk16kscn
\n\t          FROM (SELECT first_time tim,
\n\t                       first_change# gscn,
\n\t                       ((next_change# – first_change#) \/
\n\t                       ((next_time – first_time) * 24 * 60 * 60)) rate
\n\t                  FROM v$archived_log
\n\t                 WHERE (next_time > first_time)))
\n\t ORDER BY 1, 2;\n<\/p>\n

\n\t\"\"<\/a>\n<\/p>\n

\n\t\u53ef\u53c2\u8003\u4ee5\u4e0b\u94fe\u63a5\uff1a\n<\/p>\n

\n\thttps:\/\/www.cnblogs.com\/likingzi\/p\/6420927.html\n<\/p>\n

\n\t\u5176\u4ed6\uff1a\u6b64\u811a\u672c\u6765\u505apatch 13498243<\/p>\n","protected":false},"excerpt":{"rendered":"

–1\u3001\u67e5\u8be2\u5f53\u524dscn\u60c5\u51b5 select version,       … \u7ee7\u7eed\u9605\u8bfbOracle DB scn\u60c5\u51b5\u67e5\u8be2<\/span> →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[239],"_links":{"self":[{"href":"https:\/\/www.llku.com\/index.php?rest_route=\/wp\/v2\/posts\/1491"}],"collection":[{"href":"https:\/\/www.llku.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.llku.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.llku.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.llku.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1491"}],"version-history":[{"count":5,"href":"https:\/\/www.llku.com\/index.php?rest_route=\/wp\/v2\/posts\/1491\/revisions"}],"predecessor-version":[{"id":1497,"href":"https:\/\/www.llku.com\/index.php?rest_route=\/wp\/v2\/posts\/1491\/revisions\/1497"}],"wp:attachment":[{"href":"https:\/\/www.llku.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1491"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.llku.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1491"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.llku.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1491"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}