\u4e24\u4e2aTIMESTAMP\u4e4b\u5dee\u5f97\u5230\u7684\u662fINTERVAL\u7c7b\u578b\uff0c\u800c\u6709\u65f6\u6211\u4eec\u53ea\u9700\u8981\u5f97\u5230\u4e24\u4e2a\u65f6\u95f4\u76f8\u5dee\u7684\u79d2\u6570\uff0c\u5982\u679c\u53d8\u6210INTERVAL\u4e4b\u540e\uff0c\u60f3\u8981\u83b7\u53d6\u8fd9\u4e2a\u503c\u4f1a\u975e\u5e38\u9ebb\u70e6\u3002
\n\u6bd4\u8f83\u5e38\u89c1\u7684\u65b9\u6cd5\u662f\u4f7f\u7528EXTRACT\u6765\u62bd\u53d6\u83b7\u5f97\u7684INTERVAL\u7c7b\u578b\u7684\u65e5\u3001\u65f6\u3001\u5206\u548c\u79d2\u6765\u5206\u522b\u8ba1\u7b97\u5e76\u6c42\u548c\uff1a<\/p>\n
SQL> create table t_timestamp (id number, t1 timestamp, t2 timestamp);\r\nTable created.\r\nSQL> insert into t_timestamp \r\n2 values (1, to_timestamp('20120603222324', 'yyyymmddhh24miss'), to_timestamp('20120526152354', 'yyyymmddhh24miss'));\r\n1 row created.\r\nSQL> commit;\r\nCommit complete.\r\nSQL> select t1 - t2 from t_timestamp where id = 1;\r\nT1-T2\r\n---------------------------------------------------------------------------\r\n+000000008 06:59:30.000000\r\nSQL> with t as (select t1 - t2 interval from t_timestamp where id = 1)\r\n2 select extract(day from interval) * 86400\r\n3 + extract(hour from interval) * 3600\r\n4 + extract(minute from interval) * 60\r\n5 + extract(second from interval) interval\r\n6 from t; \r\nINTERVAL\r\n----------\r\n716370<\/pre>\n\u5bf9\u4e8e\u4e0d\u9700\u8981\u8003\u8651\u6beb\u79d2\u7684\u60c5\u51b5\u800c\u8a00\uff0c\u8fd9\u79cd\u8ba1\u7b97\u8fc7\u4e8e\u9ebb\u70e6\u4e86\uff0c\u800c\u5bf9\u4e8eDATE\u7c7b\u578b\u800c\u8a00\uff0c\u8ba1\u7b97\u5dee\u503c\u975e\u5e38\u65b9\u4fbf\uff0c\u76f4\u63a5\u5c31\u53ef\u4ee5\u8fd4\u56de\u4e24\u4e2a\u65e5\u671f\u76f8\u5dee\u7684\u5929\u6570\uff0c\u5728\u4e58\u4ee586400\u5c31\u53ef\u4ee5\u5f97\u5230\u7ed3\u679c\u3002
\n\u53ef\u60dc\u7684\u662f\uff0c\u65e0\u8bba\u662fROUND\u8fd8\u662fTRUNC\u53c2\u6570\uff0c\u90fd\u4e0d\u652f\u6301TIMESTAMP\u7c7b\u578b\uff1a<\/p>\n
SQL> select trunc(t1, 'ss') from t_timestamp where id = 1;\r\nselect trunc(t1, 'ss') from t_timestamp where id = 1\r\n*\r\nERROR at line 1:\r\nORA-01899: bad precision specifier\r\n\r\nSQL> select round(t1, 'ss') from t_timestamp where id = 1;\r\nselect round(t1, 'ss') from t_timestamp where id = 1\r\n*\r\nERROR at line 1:\r\nORA-01899: bad precision specifier<\/pre>\n\u5176\u5b9e\u5bf9\u4e8e\u8fd9\u4e2a\u95ee\u9898\uff0c\u6700\u7b80\u5355\u7684\u65b9\u6cd5\u662f\u5229\u7528\u9690\u5f0f\u8f6c\u6362\uff0c\u53d8\u6210DATE\u7c7b\u578b\u7684\u64cd\u4f5c\uff1a<\/p>\n
SQL> select (t1 - 0 - (t2 - 0)) * 86400 from t_timestamp;\r\n(T1-0-(T2-0))*86400\r\n-------------------\r\n716370<\/pre>\n\u5f53\u7136\u6700\u6807\u51c6\u7684\u65b9\u6cd5\u8fd8\u662f\u663e\u793a\u7684\u8f6c\u6362\uff1a<\/p>\n
SQL> select (cast(t1 as date) - cast(t2 as date)) * 86400 from t_timestamp;\r\n(CAST(T1ASDATE)-CAST(T2ASDATE))*86400\r\n-------------------------------------\r\n716370<\/pre>\n\u663e\u7136\u8fd9\u79cd\u65b9\u4fbf\u6bd4\u5229\u7528EXTRACT\u8981\u7b80\u5355\u5f97\u591a\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u4e24\u4e2aTIMESTAMP\u4e4b\u5dee\u5f97\u5230\u7684\u662fINTERVAL\u7c7b\u578b\uff0c\u800c\u6709\u65f6\u6211\u4eec\u53ea\u9700\u8981\u5f97\u5230\u4e24\u4e2a\u65f6\u95f4\u76f8\u5dee\u7684\u79d2\u6570\uff0c\u5982\u679c\u53d8\u6210INTERVAL\u4e4b\u540e\uff0c\u60f3\u8981\u83b7\u53d6\u8fd9\u4e2a\u503c\u4f1a\u975e\u5e38\u9ebb\u70e6\u3002 \u6bd4\u8f83\u5e38\u89c1\u7684\u65b9\u6cd5\u662f\u4f7f\u7528EXTRACT\u6765\u62bd\u53d6\u83b7\u5f97\u7684INTERVAL\u7c7b\u578b\u7684\u65e5\u3001\u65f6\u3001\u5206\u548c\u79d2\u6765\u5206\u522b\u8ba1\u7b97\u5e76\u6c42\u548c\uff1a SQL> create table t_timestamp (id number, t1 timestamp, t2 timestamp); Table created. SQL> insert into t_timestamp 2 values (1, to_timestamp(‘20120603222324’, ‘yyyymmddhh24miss’), to_timestamp(‘20120526152354’, ‘yyyymmddhh24miss’)); 1 row created. SQL> commit; Commit complete. SQL> select t1 – t2 from t_timestamp where … Continue reading