You own a table called EMPLOYEES with this table structure:
EMPLOYEE_ID NUMBER Primary Key
FIRST_NAME VARCHAR2(25)
LAST_NAME VARCHAR2(25)
HIRE_DATE DATE
What happens when you execute this DELETE statement?
DELETE employees;（）
A.You get an error because of a primary key violation.
B.The data and structure of the EMPLOYEES table are deleted.
C.The data in the EMPLOYEES table is deleted but not the structure.
D.You get an error because the statement is not syntactically correct.
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The CUSTOMERS table has these columns:
CUSTOMER_ID NUMBER(4) NOT NULL
CUSTOMER_NAME VARCHAR2(100) NOT NULL
STREET_ADDRESS VARCHAR2(150)
CITY_ADDRESS VARCHAR2(50)
STATE_ADDRESS VARCHAR2(50)
PROVINCE_ADDRESS VARCHAR2(50)
COUNTRY_ADDRESS VARCHAR2(50)
POSTAL_CODE VARCHAR2(12)
CUSTOMER_PHONE VARCHAR2(20)
The CUSTOMER_ID column is the primary key for the table.
You need to determine how dispersed your customer base is. Which expression finds the number of different countries represented in the CUSTOMERS table?（）
A.COUNT(UPPER(country_address))
B.COUNT(DIFF(UPPER(country_address)))
C.COUNT(UNIQUE(UPPER(country_address)))
D.COUNT DISTINCT UPPER(country_address)
E.COUNT(DISTINCT (UPPER(country_address)))
A.ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;
B.ALTER TABLE customers MODIFY CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;
C.ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn NOT NULL;
D.ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn IS NOT NULL;
E.ALTER TABLE customers MODIFY name CONSTRAINT cust_name_nn NOT NULL;
F.ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name NOT NULL;
Click the Exhibit button and examine the data from the EMP table.
The COMMISSION column shows the monthly commission earned by the employee.
Which two tasks would require subqueries or joins in order to be performed in a single step? （）
A.listing the employees who earn the same amount of commission as employee 3
B.finding the total commission earned by the employees in department 10
C.finding the number of employees who earn a commission that is higher than the average commission of the company
D.listing the departments whose average commission is more than 600
E.listing the employees who do not earn commission and who are working for department 20 in descending order of the employee ID
F.listing the employees whose annual commission is more than 6000
A.Null values are left out of the sort.
B.Character values are displayed from Z to A
C.Date values are displayed with the earliest value first.
D.Null values are displayed last for descending sequences.
E.Numeric values are displayed with the lowest values first.
A.COMMIT
B.MERGE
C.UPDATE
D.DELETE
E.CREATE
F.DROP...
Click the Exhibit button and examine the data in the EMPLOYEES table.
Examine the subquery:
SELECT last_name
FROM employees
WHERE salary IN (SELECT MAX(salary)
FROM employees
GROUP BY department_id);
Which statement is true?（）
A.The SELECT statement is syntactically accurate.
B.The SELECT statement does not work because there is no HAVING clause.
C.The SELECT statement does not work because the column specified in the GROUP BY clause is not in the SELECT list.
D.The SELECT statement does not work because the GROUP BY clause should be in the main query and not in the subquery.
A.TRIM
B.REPLACE
C.TRUNC
D.TO_DATE
E.MOD
F.CASE
A.iSQL*Plus commands cannot be abbreviated.
B.iSQL*Plus commands are accessed from a browser.
C.iSQL*Plus commands are used to manipulate data in tables.
D.iSQL*Plus commands manipulate table definitions in the database.
E.iSQL*Plus is the Oracle proprietary interface for executing SQL statements.
A.Both tables have NULL values.
B.You want all unmatched data from one table.
C.You want all matched data from both tables.
D.You want all unmatched data from both tables.
E.One of the tables has more data than the other.
F.You want all matched and unmatched data from only one table.
A.Asinglerowsubquerycanretrieveonlyonecolumnandonerow.
B.Asinglerowsubquerycanretrieveonlyonerowbutmanycolumns.
C.Amultiplerowsubquerycanretrievemultiplerowsandmultiplecolumns.
D.Amultiplerowsubquerycanbecomparedusingthe"；>；"；operator.
E.AsinglerowsubquerycanusetheINoperator.
F.Amultiplerowsubquerycanusethe"；="；operator.
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