先試後買

A. quantity, unit_price

B. total_paid

C. product_id

D. quantity

E. quantity * unit_price

A. It fails unless the expression is modified to TO-CHAR(SUNBSTR(SYSDATE,1,5)

B. It fails unless the expression is modified to SUBSTR (TO_ CHAR(SYSDATE),1,5)

C. It executes successfully with an implicit data type conversion

D. It fails unless the expression is modified to SUBSTR (TO_ CHAR(TRUNC(SYSDATE)),1,5)

A. SELECT product id, quantity on hand, supplier id
FROM product information
NATURAL JOIN inventories AND quantity .on hand < 5;

B. SELECT i. product_id, i. quantity_on hand, pi. supplier id
FROM product information pi JOIN inventories i USING (product id) AND quantity .on hand < 5;

C. SELECT i. product id, i. quantity .on hand, pi. supplier_id
FROM product_information pi JOIN inventories i
ON (pi. product. id=i. product id) AND quantity on hand < 5;

D. SELECT i.product id, i. quantity on hand, pi. supplier id
FROM product information pi JOIN inventories i
ON (pi.product id=i. product id)WHERE quantity on hand < 5;

A. PRODUCT_ID can be assigned the PEIMARY KEY constraint.

B. PRODUCT_PRICE contains the value zero by default if no value is assigned to it.

C. EXPIRY_DATE cannot be used in arithmetic expressions.

D. EXPIRY_DATE contains the SYSDATE by default if no date is assigned to it

E. PRODUCT_NAME cannot contain duplicate values.

F. PRODUCT_PRICE can be used in an arithmetic expression even if it has no value stored in it

A. SELECT COUNT (* )
FROM employees
WHERE salary < (SELECT salary FROM employees WHERE employee_id =
110) ;

B. SELECT COUNT (*)
FROM employees e
JOIN (SELECT salary FROM employees WHERE employee_id= 110) a
ON e. salary< a. salary;

C. SELECT COUNT (*)
FROM employees
JOIN employees a
ON e. salary< a. salary
WHERE a. employee_id= 110;

D. SELECT COUNT (* )
FROM employees e
WHERE e. salary < (SELECT a. salary FROM employees a WHERE e. employee_id = 110);

A.

B.

C.

D.

E.

A. CEIL: can be used for positive and negative numbers

B. CONCAT: can be used to combine any number of values

C. FLOOR: returns the smallest integer greater than or equal to a specified number

D. TRUNC: can be used with NUMBER and DATE values

E. MOD: returns the quotient of a division operation

A. LEFT OUTER JOIN with self join

B. self Join

C. PULL OUTER JOIN with self join

D. subquery

E. RIGHT OUTER JOIN with self join

A. Constraints are enforced only during INSERT operations.

B. A constraint can be disabled even if the constrained column contains data.

C. All constraints can be defined at the table or column level.

D. A column with a UNIQUE constraint can contain a NULL value.

E. A column with a foreign key constraint can never contain a null value.

A. A user can always see uncommitted updates made by the same user in a different session.

B. If a session has an uncommitted transaction, then a DDL statement issue a COMMIT before starting a new transaction.

C. A session can always see uncommitted updates made by itself.

D. An uncommitted transaction commits automatically if the user exits SQL*Plus

E. Data Manipulation Language (DML) statements always start a new transaction.

F. A Data Definition Language (DDL) statement does a commit automatically only for the data dictionary updates caused by the DDL