36.Examine this command
Which two statements are true?
A.DML, may be performed on tables with one or more extents in this data file during the
execution of this command
B.It overwrites any existing file with the name SALES02.DBF in /u02 by default.
C.Tables with one or more extents in this data file may be queried during the execution of this command
D.Compressed objects in sales01.DBF will be uncompressed in SALES02.DBF after the move E.The “To” clause containing the new file name must be specified even if Oracle Managed Files (OMF)is used
答案： AC
https://docs.oracle.com/en/database/oracle/oracle-database/12.2/admin/managing-data-files-and-temp-files.html#GUID-B0CB3536-EB2D-4319-9563-D698905E67D4
37.Which two statements are true about substitution variables?
A.A substitution variable used to prompt for a column name must be enclosed in double quotation marks.
B.A substitution variable prefixed with s always prompts only once for a value in a session
C.A substitution variable used to prompt for a column name must be enclosed in single quotation marks
D.A substitution variable prefixed with && prompts only once for a value in a session unless it is set to undefined in the session
E.A substitution variable can be used only in a SELECT statement
F.A substitution variable can be used with any clause in a select statement
答案： DF
38.Examine this description of the TRANSACTIONS table
Which two SQL statements execute successfully?
A.SELECT customer_id CUSTID, transaction date TRANS_DATE, amount+ 100 DUES FROM transactions
B.SELECT customer_id AS “CUSTOMER-ID”, transaction date AS DATE, amount + 100 “DUES” FROM transactions
C.SELECT customer_id AS ‘CUSTOMER-ID’, transaction date As DATE, amount + 100 ‘DUES’ FROM transactions
D.SELECT customer_id AS "CUSTOMER-ID ", transaction date As "DATE”, amount +100 DUES FROM transactions
E.SELECT customer_id AS CUSTOMER-ID, transaction date As TRANS DATE, amount 100 " DUES AMOUNT " FROM transactions
答案： AD
CUSTOMER-ID和DATE要用引号
39.Which two statements are true about the configuration and use of UNDO RETENTION with no GUARANTEED RETENTION?
A.Unexpired UNDO is always retained
B.UNDO RETENTION specifies for how long Oracle attempts to keep unexpired UNDO C.UNDO_RETENTION specifies for how long Oracle attempts to keep expired and unexpired UNDO.
D.UNDO RETENTION specifies how long all types of UNDO are retained
E.Active UNDO is always retained
答案： BE
40.The ORDERS table has a column ORDER_DATE of data type DATE. The default display format for a date is DD-MON-RR
Which two WHERE conditions demonstrate the correct usage of conversion functions?
A.WHERE order_date=TO_DATE(ADD_MONTHS(SYSDATE, 6),‘MON DD YYYY’)
B.WHERE TO_CHAR(order date, ‘MON DD YYYY’)= ‘JAN 20 2019’
C.WHERE order_date > TO_DATE(JUL 10 2018’,‘NON DD YYYY’)
D.WHERE order_date=TO_CHAR(ADD_MONTHS(SYSDATE, 6),'MON DD YYYY)
E.WHERE order_date IN (TO_DATE(‘oct 21 2018’,'mon DD YYYY '), TO_CHAR(‘Nov 21 2018’, ‘Mon DD YYYY’))
答案： BC
A不应该用to_date
D 日期和字符无法进行比较
41.Examine the description of the EMPLOYEES table NLS_DATE_FORMAT is set to DD-MON-YY
Which query requires explicit_data type conversion?
A.SELECT join_date FROM employees WHERE join_date >‘10-02-2018’;
B.SELECT join_date || ’ '|| salary FROM employees
C.SELECT salary + ‘120.50’ FROM employees
D.SELECT SUBSTR( join_date, 1, 2)-10 FROM employees
E.SELECT join_date + ‘20’ FROM employees
答案： A
