Tag: databases

Quizzes (243) Questions (4862)

Questions Related to databases

Multiple choice technology databases

You need to give the MANAGER role the ability to select from, insert into, and modify existing rows in the STUDENT_GRADES table. Anyone given this MANAGER role should be able to pass those privileges on to others. Which statement accomplishes this

  1. GRANT select, insert, update ON student_grades TO manager

  2. GRANT select, insert, update ON student_grades TO ROLE manager

  3. GRANT select, insert, modify ON student_grades TO manager WITH GRANT OPTION;

  4. GRANT select, insert, update ON student_grades TO manager WITH GRANT OPTION;
Reveal answer Fill a bubble to check yourself
D Correct answer
Full explanation
Multiple choice technology databases

Which are true about aggregate functions? (Choose all that apply)

  1. You can use aggregate functions in any caluse of the SELECT statement.

  2. You can user aggregate funcitons only in column list of select clause and where clause of select statement.

  3. You can mix single row functions with aggregate functions in the column list of a SELECT statement by grouping on single row columns.

  4. You can pass column names, expressions, constants, or functions as parameter to an aggregate function.
Reveal answer Fill a bubble to check yourself
A,D Correct answer
Full explanation
Multiple choice technology databases

The database administrator of your company created a public synonym called HR for the HUMAN_RESOURCES table of the GENERAL schema, because many users frequently use this table. As a user of the database, you created a table called HR in your schema. What happens when you execute this query? SELECT * FROM HR;

  1. You obtain the results retrieved from the public synonym HR created by the database administrator.

  2. You obtain the results retrieved from the HR table that belongs to your schema

  3. You get an error message because you cannot retrieve from a table that has the same name as a public synonym

  4. You obtain the results retrieved from both the public synonym HR and the HR table that belongs to your schema, as a Cartesian product.
Reveal answer Fill a bubble to check yourself
B Correct answer
Full explanation
Multiple choice technology databases

Evaluate the SQL statement: 1 SELECT a.emp_name, a.sal, a.dept_id, b.maxsal 2 FROM employees a, 3 (SELECT dept_id, MAX(sal) maxsal 4. FROM employees 5 GROUP BY dept_id) b 6 WHERE a.dept_id = b.dept_id 7 AND a. asl < b. maxsal; What is the result of the statement?

  1. The statement produces an error at line 1.

  2. The statement produces an error at line 3

  3. The statement produces an error at line 6.

  4. The statement returns the employee name, salary, department ID, and maximum salary earned in the department of the employee for all departments that pay less salary then the maximum salary paid in the company

  5. The statement returns the employee name, salary, department ID, and maximum salary earned in the department of the employee for all employees who earn less than the maximum salary in their department.
Reveal answer Fill a bubble to check yourself
E Correct answer
Full explanation
Multiple choice technology databases

The EMP table contains these columns: LAST NAME VARCHAR2(25) SALARY NUMBER(6,2) DEPARTMENT_ID NUMBER(6) You need to display the employees who have not been assigned to any department. You write the SELECT statement: SELECT LAST_NAME, SALARY, DEPARTMENT_ID FROM EMP WHERE DEPARMENT_ID = NULL; What is true about this SQL statement?

  1. The SQL statement displays the desired results

  2. The column in the WHERE clause should be changed to display the desired results

  3. The operator in the WHERE clause should be changed to display the desired results

  4. The WHERE clause should be changed to use an outer join to display the desired results
Reveal answer Fill a bubble to check yourself
C Correct answer
Full explanation
Multiple choice technology databases

Which two statements about subqueries are true? (Choose two.)

  1. A single row subquery can retrieve data from only one table

  2. A SQL query statement cannot display data from table B that is referred to in its subquery, unless table B is included in the main query's FROM clause.

  3. A SQL query statement can display data from table B that is referred to in its subquery, without including table B in its own FROM clause.

  4. A single row subquery can retrieve data from more than one table

  5. A single row subquery cannot be used in a condition where the LIKE operator is used for comparison

  6. A multiple-row subquery cannot be used in a condition where the LIKE operator is used for comparison.
Reveal answer Fill a bubble to check yourself
B,D Correct answer
Full explanation
Multiple choice technology databases

CREATE TABLE dept(deptno NUMBER(2),dname VARCNAR2(14),1oc VARCNAR2 (13));ROLLBACK;DESCRIBE DEPTWhat is true about the set?

  1. The DESCRIBE DEPT statement displays the structure of the DEPT table

  2. The ROLLBACK statement frees the storage space occupies by the DEPT table

  3. The DESCRIBE DEPT statement returns an error ORA-04043: object DEPT does not exist

  4. The DESCRIBE DEPT statement displays the structure of the DEPT table only if there is a COMMIT statement introduced before the ROLLBACK statement.
Reveal answer Fill a bubble to check yourself
A Correct answer
Full explanation