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;
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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.
A.USER_CONSTRAINTS
B.USER_OBJECTS
C.ALL_CONSTRAINTS
D.USER_CONS_COLUMNS
E.USER_COLUMNS
Evaluate the SQL statement
DROP TABLE DEPT;
Which four statements are true of the SQL statement? （）
A.You cannot roll back this statement.
B.All pending transactions are committed.
C.All views based on the DEPT table are deleted.
D.All indexes based on the DEPT table are dropped.
E.All data in the table is deleted, and the table structure is also deleted.
F.All data in the table is deleted, but the structure of the table is retained.
G.All synonyms based on the DEPT table are deleted.
最新试题
The user Alice wants to grant all users query privileges on her DEPT table. Which SQL statement accomplishes this? （）
Which three are true? （）
Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary KeyFIRST_NAME VARCHAR2 (25)LAST_NAME VARCHAR2 (25)HIRE_DATE DATEWhich UPDATE statement is valid? （）
You need to design a student registration database that contains several tables storing academic information.The STUDENTS table stores information about a student. The STUDENT_GRADES table storesinformation about the student's grades. Both of the tables have a column named STUDENT_ID. The STUDENT_ID column in the STUDENTS table is a primary key.You need to create a foreign key on the STUDENT_ID column of the STUDENT_GRADES table thatpoints to the STUDENT_ID column of the STUDENTS table. Which statement creates the foreign key?（）
Examine the structure of the EMPLOYEES table:EMPLOYEE_ID NUMBER NOT NULL, Primary KeyEMP_NAME VARCHAR2(30)JOB_ID NUMBER\SAL NUMBERMGR_ID NUMBER References EMPLOYEE_ID columnDEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table You created a sequence called EMP_ID_SEQ inorderto populate sequential values for the EMPLOYEE_ID column of the EMPLOYEES table. Which two statements regarding the EMP_ID_SEQ sequence are true? （）
Which constraint can be defined only at the column level? （）
What is true regarding subqueries?（）
For which action can you use the TO_DATE function? （）
Evaluate the SQL statement: TRUNCATE TABLE DEPT; Which three are true about the SQL statement? （）
The PRODUCTS table has these columns:PRODUCT_ID NUMBER(4)PRODUCT_NAME VARCHAR2(45)PRICE NUMBER(8,2)Evaluate this SQL statement:SELECT *FROM PRODUCTSORDER BY price, product _ name;What is true about the SQL statement? （）