Cursor的好處
將大的事務切割成小的事務,這樣可以減少undo的需求及鎖的掌控時間example:1. 創建一個大表lock_test01,創建遊標並使用它declarecursor test_cur isselect * from lock_test01 where name='YAO';v_test lock_test01%rowtype;beginopen test_cur;loopfetch test_cur into v_test;insert into lock_test02 values(v_test.name,v_test.pnl);commit;exit when test_cur%notfound;end loop;end;/2.開啟另一個sqlplus, 查看先前鎖的狀況SQL> SELECT sid,type,id1,id2,lmode,request,block FROM V$LOCK WHERE SID=9;SQL> SELECT sid,type
Shared Server
启用SHARED SERVERS和关闭只需要把SHARED_SERVERS设置为大于1的值,系统即转为SHARED SERVER。关闭SHARED SERVERS只需要把该参数设置为0。SQL> alter system set shared_servers=2; #更改已成功系统已更改。SQL> select name,status from v$shared_server; #结果显示有S000和S001两个SHARED SERVERS PROCESS正运行NAME STATUS---- ----------------S000 WAIT(COMMON)S001 WAIT(COMMON)SQL> alter system set dispatchers="(protocol=tcp)(dispatcher=2)";系统已更改。SQL> select name,status,accept as
動詞+ed的發音
动词加ed的读音主要有三种: 以清辅音结尾的读t,如worked 以浊辅音结尾的读d,如rained. 以t和d结尾的读id.如nee清请,浊浊 动词结尾音为 t/d 后都发id的音 如 created/planted 动词结尾为元音后发d以清辅音结尾的读t,如helped, laughed 以浊辅音结尾的读d,如rained, puzzled 以t和d结尾的读id,如needed,wanted 以元音结尾的读d,如played, answered 的音ded[@more@]