发布时间：2022-01-19 14:24:57

16.Which three statements are true about dropping and unused columns in an Oracle database?(Choose three.)A. A primary key column referenced by another column as a foreign key can be dropped if using the CASCADE option.B. An UNUSED column’s space is reclaimed automatically when the bloc.........【阅读全文】

发布时间：2022-01-17 11:37:17

15.Examine this command:ALTER DATABASEMOVE DATAFILE '/u01/sales1.dbf'TO /u01/sales01.dbf'REUSE;Which two statements are true? (Choose two.)A. DML may be performed on tables with one or more extents in this data file during the execution of this command.B. The tablespac.........【阅读全文】

发布时间：2022-01-14 15:48:38

14、choose oneExamine the description of the CUSTOMERS table:name null? type------------------------CUST_ID NOT NULL VARCHAR2(6)FIRST_NAME VARCHAR2(50)LAST_NAME NOT NULL VARCHAR2(50)ADDRESS VARCHAR2(50)CITY VARCHAR2(50)You want to display details of all customer.........【阅读全文】

发布时间：2022-01-13 17:43:23

13.You want to write a query that prompts for two column names and the WHERE condition each time it is executed in a session but only prompts for the table name the first time it is executed.The variables used in your query are never undefined in your session.Which query can be used?.........【阅读全文】

发布时间：2022-01-11 14:58:50

12.Which three statements are true about a self-join? (Choose three.)A. The ON clause must be usedB. The query must use two different aliases for the tableC. It must be an equi joinD. It must be an inner joinE. The ON clause can be usedF. It can be an outer join.........【阅读全文】