ocp1z0-047: Time Format

This topic is the test time format, the date of the storage format, within the Oracle is composed of the following seven parts: Century, year, month, day, hour, minute, second.

OK, let's do a test:

Gyj@ocm> CREATE TABLE Gyj_order (order_id int,order_date date);

Table created.

gyj@ocm> INSERT into Gyj_order values (1,sysdate);

1 row created.

Gyj@ocm> commit;

Commit complete.

Gyj@ocm> SELECT * from Gyj_order where order_date> to_date (' June 2006 ', ' MON ddyyyy ');

Order_idorder_dat

---------- ---------

116-jul-13

Explain answer a is correct

Gyj@ocm> SELECT * from Gyj_order whereto_char (order_date, ' MON DD YYYY ') = ' June 16 2013 ';

Order_idorder_dat

---------- ---------

116-jul-13

Explain the answer b is correct

Gyj@ocm> Select To_char (add_months (sysdate,6), ' mondd YYYY ') from dual;

To_char (Add_mo

--------------

16 2014.

Gyj@ocm> SELECT * from Gyj_order whereorder_date> to_char (add_months (sysdate,6), ' MON DD YYYY ');

SELECT * from Gyj_order where Order_date>to_char (Add_months (sysdate,6), ' MON DD YYYY ')

*

ERROR at line 1:

Ora-01858:a non-numeric character is found where Anumeric was expected

EXPLANATION The answer c is incorrect, the time type and the character type cannot be compared

Gyj@ocm> SELECT * from Gyj_order where Order_datein (To_date (' 2013 ', ' MON dd YYYY '), To_char (' June 2013 ', ' MON DD YYYY '));

SELECT * from Gyj_order where Order_datein (To_date (' 2013 ', ' MON dd YYYY '), To_char (' June 2013 ', ' MON dd YYYY '))

*

ERROR at line 1:

Ora-01722:invalid number

Gyj@ocm> Select To_char (' 2013 ', ' MON ddyyyy ') from dual; Select To_char (' June 2013 ', ' MON DD YYYY ') from dual

*

ERROR at line 1:

Ora-01722:invalid number

The above writing is wrong, already is the character does not need to use the TO_CHAR transformation, looks the following writing is correct:

Gyj@ocm> Select To_char (to_date (' 2013 ', ' mondd YYYY '), ' MON DD YYYY ') from dual;

To_char (to_

-----------

April 16 2013

There are also time and character types can not be directly calculated, the following error:

Gyj@ocm> SELECT * from Gyj_order where Order_datein (To_char (To_date (' June 2013 ', ' MON dd YYYY '), ' MON dd YYYY '));

SELECT * from Gyj_order where Order_datein (To_char (To_date (' 2013 ', ' MON dd YYYY '), ' MON dd YYYY '))

*

ERROR at line 1:

Ora-01858:a non-numeric character is found where Anumeric was expected

Answer d is not correct

Final correct answer selected: AB

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