Oracle认证考试

The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL

题目

The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) Which statement finds the rows in the CUSTOMERS table that do not have a postal code? （）

  • A、SELECT customer_id, customer_name FROM customers WHERE postal_code CONTAINS NULL;
  • B、SELECT customer_id, customer_name FROM customers WHER postal_code = ' ___________';
  • C、SELECT customer_id, customer_name FROM customers WHERE postal _ code IS NULL;
  • D、SELECT customer_id, customer_name FROM customers WHERE postal code IS NVL;
  • E、SELECT customer_id, customer_name FROM customers WHERE postal_code = NULL;
参考答案和解析
正确答案:C
如果没有搜索结果，请直接 联系老师 获取答案。
相似问题和答案

第1题：

Examine this command:SQL > exec DBMS_STATS.SET_TABLE_PREFS (‘SH’, ‘CUSTOMERS’, ‘PUBLISH’, ‘false’);Which three statements are true about the effect of this command?()

A. Statistics collection is not done for the CUSTOMERS table when schema stats are gathered.

B. Statistics collection is not done for the CUSTOMERS table when database stats are gathered.

C. Any existing statistics for the CUSTOMERS table are still available to the optimizer at parse time.

D. Statistics gathered on the CUSTOMERS table when schema stats are gathered are stored as pending statistics.

E. Statistics gathered on the CUSTOMERS table when database stats are gathered are stored as pending statistics.


参考答案：A, C, D

第2题：

In which situations does the Oracle Data Pump use external tables and not the direct path load whileexporting a table（）

  • A、if a table is not in a cluster
  • B、if a table has an active trigger
  • C、if a table has an encrypted
  • D、if a table has a column of data type LONG defined on it
  • E、if a table has a referential integrity constraint defined on it

正确答案:B,C,E

第3题：

Which statement adds a constraint that ensures the CUSTOMER_NAME column of the CUSTOMERS table holds a value?()

A. ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;

B. ALTER TABLE customers MODIFY CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;

C. ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn NOT NULL;

D. ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn IS NOT NULL;

E. ALTER TABLE customers MODIFY name CONSTRAINT cust_name_nn NOT NULL;

F. ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name NOT NULL;


参考答案：C

第4题：

Examine the command： SQL> DBMS_STATS.SET_TABLE_PREFS（’SH’， ’CUSTOMERS’， ’PUBLISH’， ’false’）；  Which statementdescribes the effect of the above command（）

  • A、Automatic statistics collection is stopped for the CUSTOMERS table.
  • B、Statistics for the CUSTOMERS table are locked and cannot be overwritten.
  • C、Existing statistics for the CUSTOMERS table become unusable for the query optimizer.
  • D、Subsequently， statistics gathered on the CUSTOMERS table are stored as pending statistics

正确答案:D

第5题：

The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) Which statement finds the rows in the CUSTOMERS table that do not have a postal code?（）

  • A、SELECT customer_id, customer_name FROM customers WHERE postal_code CONTAINS NULL;
  • B、SELECT customer_id, customer_name FROM customers WHER postal_code = ' ___________';
  • C、SELECT customer_id, customer_name FROM customers WHERE postal _ code IS NULL;
  • D、SELECT customer_id, customer_name FROM customers WHERE postal code IS NVL;
  • E、SELECT customer_id, customer_name FROM customers WHERE postal_code = NULL;

正确答案:C

第6题：

You need to produce a report for mailing labels for all customers. The mailing label must have only the customer name and address. The CUSTOMERS table has these columns: CUST_ID NUMBER(4) NOT NULL CUST_NAME VARCHAR2(100) NOT NULL CUST_ADDRESS VARCHAR2(150) CUST_PHONE VARCHAR2(20) Which SELECT statement accomplishes this task?（）

  • A、SELECT* FROM customers;
  • B、SELECT name, address FROM customers;
  • C、SELECT id, name, address, phone FROM customers;
  • D、SELECT cust_name, cust_address FROM customers;
  • E、SELECT cust_id, cust_name, cust_address, cust_phone FROM customers;

正确答案:D

第7题：

You are working in an online transaction processing （OLTP） environment. You used the FLASHBACK TABLE command to flash back the CUSTOMERS table. Before executing the FLASHBACK TABLE command， the System Change Number （SCN） was 663571. After flashing back the CUSTOMERS table，you realize that the table is not in the correct state and the resultant changes are not what you had desired. So， you need to reverse the effects of the FLASHBACK TABLE command while ensuring that：  a） No other user data in the database is affected.  b） The operation takes the minimum possible time.  Which option would you choose？（） 

  • A、use the ROLLBACK command with SCN 663571
  • B、perform Flashback Transaction Query with SCN 663571
  • C、execute the FLASHBACK DATABASE statement to retrieve the CUSTOMERS table as it was at SCN 663571
  • D、execute another FLASHBACK TABLE statement to retrieve the CUSTOMERS table as it was at SCN 663571

正确答案:D

第8题：

Youexecutedthefollowingcommands：SQL>ALTERSESSIONSETOPTIMIZER_USE_PENDING_STATISTICS=false；SQL>EXECUTEDBMS_STATS.SET_TABLE_PREFS（’SH’，’CUSTOMERS’，’PUBLISH’，’false’）；SQL>EXECUTEDBMS_STATS.GATHER_TABLE_STATS（’SH’，’CUSTOMERS’）；WhichstatementiscorrectregardingtheabovestatisticscollectionontheSH.CUSTOMERStableintheabovesession？（）

A.Thestatisticsarestoredinthependingstatisticstableinthedatadictionary.

B.Thestatisticsaretreatedasthecurrentstatisticsbytheoptimizerforallsessions.

C.Thestatisticsaretreatedasthecurrentstatisticsbytheoptimizerforthecurrentsessionsonly.

D.Thestatisticsaretemporaryandusedbytheoptimizerforallsessionsuntilthissessionterminates.


参考答案：A

第9题：

The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) The CUSTOMER_ID column is the primary key for the table. Which two statements find the number of customers? （）

  • A、SELECT TOTAL(*) FROM customer;
  • B、SELECT COUNT(*) FROM customer;
  • C、SELECT TOTAL(customer_id) FROM customer;
  • D、SELECT COUNT(customer_id) FROM customer;
  • E、SELECT COUNT(customers) FROM customer;
  • F、SELECT TOTAL(customer_name) FROM customer;

正确答案:B,D

第10题：

You executed the following commands：   SQL> ALTER SESSION SET OPTIMIZER_USE_PENDING_STATISTICS = false； SQL> EXECUTE DBMS_STATS.SET_TABLE_PREFS（’SH’， ’CUSTOMERS’， ’PUBLISH’，’false’）； SQL> EXECUTE DBMS_STATS.GATHER_TABLE_STATS（’SH’， ’CUSTOMERS’）；   Which statement is correct regarding the above statistics collection on the SH.CUSTOMERS table in the above session？（）

  • A、 The statistics are stored in the pending statistics table in the data dictionary.
  • B、 The statistics are treated as the current statistics by the optimizer for all sessions.
  • C、 The statistics are treated as the current statistics by the optimizer for the current sessions only.
  • D、 The statistics are temporary and used by the optimizer for all sessions until this session terminates.

正确答案:A

更多相关问题
相关内容