A. The indexed column is declared as NOT NULL.
B. The indexed columns are used in the FROM clause.
C. The indexed columns are part of an expression.
D. The indexed column contains a wide range of values.
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A. You can use aggregate functions in any clause of a SELECT statement.
B. You can use aggregate functions only in the column list of the SELECT clause and in the WHERE clause of a SELECT statement.
C. You can mix single row columns with aggregate functions in the column list of a SELECT statement by grouping on the single row columns.
D. You can pass column names, expressions, constants, or functions as parameters to an aggregate function.
E. You can use aggregate functions on a table, only by grouping the whole table as one single group.
F. You cannot group the rows of a table by more than one column while using aggregate functions.
A./SQL*Plus commands cannot be abbreviated.
B./SQL*Plus commands are accessed from a browser.
C./SQL*Plus commands are used to manipulate data in tables.
D./SQL*Plus commands manipulate table definitions in the database.
E./SQL*Plus is the Oracle proprietary interface for executing SQL statements.
Examine the structure if the EMPLOYEES and NEW EMPLOYEES tables:
Which MERGE statement is valid?（）
A.
B.
C.
D.
Examine the structure of the EMPLOYEES table:
EMPLOYEE_ID NUMBER Primary Key
FIRST_NAME VARCHAR2(25)
LAST_NAME VARCHAR2(25)
HIRE_DATE DATE
You issue these statements:
CREATE table new_emp ( employe_id NUMBER, name VARCGAR2(30)); INSERT INTO new_emp SELECT employee_id, last_name from employees; Savepoint s1;
UPDATE new_emp set name = UPPER(name);
Savepoint s2;
Delete from new_emp;
Rollback to s2;
Delete from new_emp where employee_id=180;
UPDATE new_emp set name = 'James';
Rollback to s2;
UPDATE new_emp sey name = 'James' Where employee_id=180;
Rollback;
At the end of this transaction, what is true?（）
A. You have no rows in the table.
B. You have an employee with the name of James.
C. You cannot roll back to the same savepoint more than once.
D. Your last update fails to update any rows because employee ID 180 was already deleted.
A. Scott can create a synonym for the EMP_DEPT_LOC_VU bus using the command: CREATE PRIVATE SYNONYM EDL_VU FOR mary.EMP DEPT_LOC_VU; then he can prefix the columns with this synonymn.
B. Scott can create a synonym for the EMP_DEPT_LOC_VU by using the command: CREATE SYNONYM EDL_VU FOR mary.EMP_DEPT_LOC_VU; then he can prefix the columns with this synonym.
C. Scott can create a synonym for the EMP_DEPT_LOC_VU by using the command: CREATE LOCAL SYNONYM EDL_VU FOR mary.EMP DEPT_LOC_VU; then he can prefix the columns with this synonym.
D. Scott can create a synonym for the EMP_DEPT_LOC_VU by using the command: CREATE SYNONYM EDL_VU ON mary(EMP_DEPT_LOC_VU); then he can prefix the columns with this synonym.
E. Scott cannot create a synonym because synonyms can be created only for tables.
F. Scott cannot create any synonym for Mary's view. Mary should create a private synonym for the view and grant SELECT privilege on that synonym to Scott.
A.COMMIT
B.MERGE
C.UPDATE
D.DELETE
E.CREATE
F.DROP
The STUDENT_GRADES table has these columns:
The registrar has asked for a report on the average grade point average (GPA) for students enrolled during semesters that end in the year 2000. Which statement accomplish this?（）
A.
B.
C.
D.
E.
F.
Examine the structures of the EMPLOYEES and TAX tables.
EMPLOYEES
EMPLOYEE_ID NUMBER NOT NULL, Primary
Key
EMP_NAME VARCHAR2 (30)
JOB_ID VARCHAR2 (20)
SALARY NUMBER
References
MGR_ID NUMBER
EMPLOYEE_ID
column
DEPARTMENT_ID NUMBER Foreign key to
DEPARTMENT _ID
column of the
DEPARTMENT table
TAX
MIN_SALARY NUMBER
MAX_SALARY NUMBER
TAX_PERCENT NUMBER
Percentage tax for given
salary range
You need to find the percentage tax applicable for each employee. Which SQL statement would you use?（）
A. SELECT employee_id, salary, tax_percent FROM employees e, tax t WHERE e.salary BETWEEN t.min _ salary AND t.max_salary
B. SELECT employee_id, salary, tax_percent FROM employees e, tax t WHERE e.salary > t.min_salary, tax_percent
C. SELECT employee_id, salary, tax_percent FROM employees e, tax t WHERE MIN(e.salary) = t.min_salary AND MAX(e.salary) = t.max_salary
D. You cannot find the information because there is no common column between the two tables.
A. The sort is in ascending by order by default.
B. The sort is in descending order by default.
C. The ORDER BY clause must precede the WHERE clause.
D. The ORDER BY clause is executed on the client side.
E. The ORDER BY clause comes last in the SELECT statement.
F. The ORDER BY clause is executed first in the query execution.
A.Convert 10 to 'TEN'
B.Convert '10' to 10
C.Convert '10' to '10'
D.Convert 'TEN' to 10
E.Convert a date to a character expression
F.Convert a character expression to a date
最新试题
Which SQL statement displays the date March 19, 2001 in a format that appears as "Nineteenth of March 2001 12:00:00 AM"? （）
Which two statements about subqueries are true? （）
User Mary has a view called EMP_DEPT_LOC_VU that was created based on the EMPLOYEES, DEPARTMENTS, and LOCATIONS tables. She has the privilege to create a public synonym, and would like to create a synonym for this view that can be used by all users of the database. Which SQL statement can Mary use to accomplish that task?（）
Which two statements about subqueries are true? （）
Which constraint can be defined only at the column level? （）
Which four are types of functions available in SQL? （）
Which two statements are true about constraints? （）
Which is a valid CREATE TABLE statement? （）
Examine the statement: Create synonym emp for hr. employees; What happens when you issue the statement? （）
Which is an iSQL*Plus command? （）