Which two statements are true about transactions in the Oracle Database serve?B) Data Manipulation Language (DML) statements always start a new transaction.D) A Data Detiniton Language (DDL) statement does a commit automatially only for the data dictionary updates caused by the DDLF) I...【阅读全文】
In the PROMOTIONS table, the PROMO_BEGTN_DATE columm is of datatype DATE and the default date format is DD-MON-RR.A) TO_NUMBER(PROMO_ BEGIN_DATE) - 5 will return numberC) PROMO_BEGIN_DATE - SYSDATE will return a number.E) PROMO_BEGIN_DATE - SYSDATE will return an error.(解析:这道...【阅读全文】
Examine this partial command:cust_id NUMBER(2),)Which two clauses are required for this command to execute successfully?B) the REJECT LIMIT clauseD) the ACCESS PARAMETERS clauseAnswer:AD【阅读全文】
Examine the description of the PRODUCTS table:-----------------------------------------------------------------PRODUCT_NANE VARCHAR2(10)PURCHARGE &nb...【阅读全文】
Which three statements are true about dropping and unused columns in an Oracle database?B) A DROP COLUMN command can be rolled backD) An UNUSED column's space is redaimed automatially when the row containing that column is next queried.F) A column that is set to NNUSED still counts tow...【阅读全文】
Which two statements are true about a self join?B) It can be a left outer join.D) It can be an inner join.Answer:BD不过在进行内连接时为了区别表的名字,需要加别名from emp2 won w.mgr=m.empno;)【阅读全文】
Which two statements are true about Oracle synonyms?B) All private synonym names must be unique in the database.D) A synonym can be created on an object in a package.(解析:同义词也是 Oracle 的一个对象;【阅读全文】
Which three statements are true about views in an Orade batabase?B) Rows inserted into a table using a view are retained in the table if the view is doppedD) Views have no segment.F) A view can be created that refers to a non-existent table in its defining query.(解析:...【阅读全文】
The EMPLOYEES table contains columns EMP_ID of data type NUMBER and HIRE_DATE of data type DATEThe NLS_TERRITORY parameter is set to AMERICA in the session and, therefore, Sunday is the first day ofthe weekA) SELECT emp_id,NEXT_DAY(ADD_MONTHS(hite_date,6), 'MONDAY') FROM employees;C) S...【阅读全文】
Which three are true about granting object privileges on tables, views, and sequences?B) DELETE can be granted on tables, views, and sequences.D) INSERT can be granted on tables, vews, and sequences.F) ALTER can be granted only on tables and sequences.(解析:update 和 delete 只能在...【阅读全文】
Exammine the desciption of the PRODUCT DETALS table:--------------------------------------------------PRODUCT_NAME NOT NULL VARCHAR2(25)EXPIRY_DATE DATEA) PRODUCT_ID can be assigned the PEIMARY KEY constraint.C) EXPIRY_DATE contains the SYSDATE by defalt if no...【阅读全文】
select * from v$log; select * from v$logfile; alter system switch logfile; select * from v$log_history; select dbid,name,created,log_mode from v$database; select recid,stamp,thread#,sequence#,name from v$archived_log; alter database add logfile group 1...【阅读全文】
------------------方法1在主库上使用备份的进行恢复丢失的归档日志------------------------------1.发现主库备份后删除了归档,但是这些归档从库还没应用,也没有传到从库从库应用的最新的归档日志为592SQL> connect / as sysdbaConnected.SQL> Select Max(t.SEQUENCE#) From V$archived_Log t;MAX(T.SEQUENCE#)--...【阅读全文】