Exam 1z0-071 topic 1 question 156 discussion

C. The EXPIRY_DATE column data type can be changed to TIMESTAMP. This is true. In Oracle, you can modify the data type of a DATE column to a TIMESTAMP data type using the ALTER TABLE statement, as long as there are no incompatible data types involved. D. The PROD_ID column can be renamed. This is true. Oracle allows you to rename columns in a table using the ALTER TABLE statement with the RENAME COLUMN clause.

ORA-01439: column to be modified must be empty to change datatype D is ok cos the same group of datatype

All are true for empty table CREATE TABLE K (ID NUMBER(2) NOT NULL,NAME VARCHAR2(20),EXPIRY_dATE DATE NOT NULL) ALTER TABLE K MODIFY NAME DEFAULT 'TEST' ALTER TABLE K MODIFY EXPIRY_dATE TIMESTAMP ALTER TABLE K RENAME COLUMN ID TO PROD_ID ALTER TABLE K MODIFY PROD_ID VARCHAR2(2)

100% C AND D HAVE A TRY: CREATE TABLE PRODUCTS_156 ( PROD_ID NUMBER(2) NOT NULL, PROD_NAME VARCHAR2(20), EXPIRY_DATE DATE ); INSERT INTO PRODUCTS_156 VALUES (1, 'Product 1', TO_DATE('2023-12-31', 'YYYY-MM-DD')); ALTER TABLE PRODUCTS_156 MODIFY EXPIRY_DATE TIMESTAMP; alter table products_156 rename column prod_id to product_id; alter table products_156 modify product_id varchar(2); (CHANGE DATA TYPE NOT ALLOWED WITH EXISTING DATA IN THE TABLE).

CD is correct in that case

in case of empty table correct will be C,E,D. But in case of existing data in the table correct will be C,D. Impossible to change datatype. System raise an error: "ORA-01439: column to be modified must be empty to change datatype"

C works well when i run sql statement.

drop table products_156; CREATE TABLE PRODUCTS_156 (PROD_ID NUMBER(2) NOT NULL, PROD_NAME VARCHAR2(20), EXPIRY_DATE DATE); ALTER TABLE PRODUCTS_156 MODIFY EXPIRY_DATE TIMESTAMP; /*C OK*/ alter table products_156 modify prod_id varchar(2); /*E OK*/ alter table products_156 rename column prod_id to product_id; /*D OK*/ desc products_156; Nombre ¿Nulo? Tipo ----------- -------- ------------ PRODUCT_ID NOT NULL VARCHAR2(2) PROD_NAME VARCHAR2(20) EXPIRY_DATE TIMESTAMP(6)