（86）Examine the structure and data of the CUST_TRANS table:

CUST_TRANS

Name Null Type

CUSTNO NOT NULL CHAR(2)

TRANSDATE DATE

TRANSAMT NUMBER(6,2)

CUSTNO TRANSDATE TRANSAMT

Dates are stored in the default date format dd-mon-rr in the CUST_TRANS table. Which SQL statements would execute successfully? (Choose three .)

A. SELECT transdate + '10' FROM cust_trans;

B. SELECT * FROM cust_trans WHERE transdate = '01-01-07';

C. SELECT transamt FROM cust_trans WHERE custno > '11';

D. SELECT * FROM cust_trans WHERE transdate='01-JANUARY-07';

E. SELECT custno + 'A' FROM cust_trans WHERE transamt > 2000;

答案：（A、C、D）

解析：

A，将'10'转换为数字10

-- B（X），提供的字符串不符合默认的日期格式

-- D，虽然默认的日期格式是短的月份，但提供长的月份也可正确执行

scott@TESTDB11>select * from emp where hiredate = '17-DECEMBER-80';

-- E,字符型数据进行加法运算，会先隐式转换为数值, 'A'转换失败

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OCP 1Z0-051-86