Oracle sql online test

1. Examine the WORKER table below:

NAME NULL TYPE
WORKER ID NOT NULL NUMBER(3)
NAME NOT NULL VARCHAR2(25)
PHONE NOT NULL VARCHAR2(9)
ADDRESS VARCHAR2(50)
POSITION UPDATE

There are hundreds of records in the EMPLOYEE TABLE. You need to modify the phone column to hold only number values. Which statement will modify the data type appropriately?

2. The emp table contains these columns:
FIRST-NAME VARCHER2(25)
COMISSION NUMBER(3,2)
Evaluate this SQL statement
SELECT first-name,commission FROM emp WHERE commission= (SELECT comission FROM emp WHERE UPPER(first-name)= ‘smith’)
Which statement will cause this statement to fail?

3. Your company will be granting workers a $150 salary increase. You need to evaluate results of the increase from the worker table prior to the actual modification. You do not want to store in the results in the current database. Which of the following is untrue?

4. You create the sal table with this command

CREATE TABLE sal (purchase-no NUMBER(9)
CONSTRAINT sale-purchase-no-pk PRIMARY KEY,
costumer-id NUMBER(9) CONSTRAINT sale-customer-id-nl NOT NULL);

Which index or indexes are created for this table?

5. You need to test if the current fetch within a PL/SQL loop was successful. Which cursor attribute is needed to accomplish this task?

6. You query a database with the following command:

SELECT dept_no, AVG (MONTHS_BETWEEN (SYSDATE, hire_date)) FROM worker_company
WHERE AVG (MONTHS_BETWEEN (SYSDATE, hire_date)) > 60
GROUP BY dept_no
ORDER BY AVG (MONTHS_BETWEEN (SYSDATE, hire_date) )

Where does the statement cause an error?

7. What command should be used to execute a script file named create_table.sql from the SQL Plus environment?

8. The emp table contains these columns:
Last_name Varchar2 (25)
First_name Varchar2 (25)
Salary Number7, 2
You need to display the names of employees on more than an average salary of all
employees. Evaluate the SQL statement.
SELECT, LAST_NAME, FIRST_NAME from emp where salary< avg(salary);

Which change should you make to achieve the desired results?

9. A group function produces ______.

10. You need to store currency data and you know that data will always have two digits to the right of the decimal points. However the number of digits to the left of the decimal place will vary greatly. Which data type would be most appropriate to store the data?

11. Examine the following command:

CREATE TABLE pay_master
(employee-id Number(9)
CONSTRAINT pay-pk PRIMARY KEY,
2000-pay NUMBER(8,2)
manager-name VARCHAR2(25)
CONSTRAINT mgr-name-nn. NOT NULL,
pay-96 NUMBER(8,2));

Which two lines of this command will return an error?

12. You need to create a report to display the ship date and order totals of your order table. If the order has not been shipped your report must display not shipped. If the total is not available your report must say not available. In the order table the ship date column has a data type of date the total column has a data type of number. Which statement do you use to create this report?

13. You must permanently remove all data from the sales_data table, but will need the table structure in the future. What single command should be issued?

14. How would you add a foreign key constraint on the dept_no column in the EMP table. Referring to the ID column in the DEPT table?

15. You have been instructed to create a report that shows different jobs in each division within your company. No duplicate roles can be displayed. Which of the following SELECT statements should be used?