Craig Willey
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College C192 Databases Quiz am C192 Practice Test, erstellt von Craig Willey am 27/06/2020.

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Craig Willey
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C192 Practice Test

Frage 1 von 52

1

Which of the following is a benefit of using a DBMS?

Wähle eine der folgenden:

  • They provide full security to data using private/public key encryption

  • They create automatic backups

  • They help create an environment for end users to have access to more data

  • They provide seamless Internet access to database data

Erklärung

Frage 2 von 52

1

The hierarchical database model is based on a ____.

Wähle eine der folgenden:

  • tree structure

  • lack of a parent segment

  • lack of a child segment

  • matrix

Erklärung

Frage 3 von 52

1

Because an RDBMS hides the system's complexity from the user/designer, ____.

Wähle eine der folgenden:

  • it does not exhibit data independence

  • it does not exhibit structural independence

  • data management is easier

  • data management is very difficult

Erklärung

Frage 4 von 52

1

The ERD is used to graphically represent the ____ database model.

Wähle eine der folgenden:

  • condensed

  • physical

  • logical

  • conceptual

Erklärung

Frage 5 von 52

1

The property of ____ enables an entity subtype to inherit the attributes and relationships of the supertype.

Wähle eine der folgenden:

  • subtype discriminator

  • inheritance

  • specialization hierarchy

  • entity supertype

Erklärung

Frage 6 von 52

1

At the implementation level, the supertype and its subtype(s) depicted in the specialization hierarchy maintain a ____ relationship.

Wähle eine der folgenden:

  • none

  • 1:1

  • 1:M

  • M:N

Erklärung

Frage 7 von 52

1

Which command would be used to delete the table row where the P_Code = '2238/QPD'?

Wähle eine der folgenden:

  • DELETE FROM PRODUCT
    WHERE P_CODE = '2238/QPD';

  • REMOVE FROM PRODUCT
    WHERE P_CODE = '2238/QPD';

  • ERASE FROM PRODUCT
    WHERE P_CODE = '2238/QPD';

  • ROLLBACK FROM PRODUCT
    WHERE P_CODE = '2238/QPD';

Erklärung

Frage 8 von 52

1

Which command is used to select partial table contents?

Wähle eine der folgenden:

  • SELECT <column(s)>
    FROM <Table name>
    WHERE <Item>;

  • LIST <column(s)>
    FROM <Table name>
    WHERE <Conditions>;

  • SELECT <column(s)>
    FROM <Table name>
    WHERE <Conditions>;

  • LIST<column(s)>
    FROM <Table name>
    WHERE <Item>;

Erklärung

Frage 9 von 52

1

Which query will output the table contents when the value of V_CODE is equal to 21344?

Wähle eine der folgenden:

  • SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE
    FROM PRODUCT
    WHERE V_CODE <> 21344;

  • SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE
    FROM PRODUCT
    WHERE V_CODE <= 21344;

  • SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE
    FROM PRODUCT
    WHERE V_CODE = 21344;

  • SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE
    FROM PRODUCT
    WHERE V_CODE => 21344;

Erklärung

Frage 10 von 52

1

What is the command used to list the P_CODE, P_DESCRIPT, P_INDATE, and P_PRICE fields from the Product table in ascending order by P_PRICE?

Wähle eine der folgenden:

  • SELECT P_CODE, P_DESCRIPT, P_INDATE, P_PRICE
    FROM PRODUCT
    SEQUENCE BY P_PRICE;

  • SELECT P_CODE, P_DESCRIPT, P_INDATE, P_PRICE
    FROM PRODUCT
    LIST BY P_PRICE;

  • SELECT P_CODE, P_DESCRIPT, P_INDATE, P_PRICE
    FROM PRODUCT
    ORDER BY P_PRICE;

  • SELECT P_CODE, P_DESCRIPT, P_INDATE, P_PRICE
    FROM PRODUCT
    ASCENDING BY P_PRICE;

Erklärung

Frage 11 von 52

1

The basic SQL aggregate function that gives the total of all values for a selected attribute in a given column is ____.

Wähle eine der folgenden:

  • COUNT

  • MIN

  • MAX

  • SUM

Erklärung

Frage 12 von 52

1

____ is used to tally the number of specific "values" of an attribute.

Wähle eine der folgenden:

  • SUM

  • TOTAL

  • COUNT

  • ADD

Erklärung

Frage 13 von 52

1

UPDATE tablename
*****
[WHERE conditionlist];
What command replaces the ***** in the above statement?

Wähle eine der folgenden:

  • SET columnname = expression

  • columnname = expression

  • expression = columnname

  • LET columnname = expression

Erklärung

Frage 14 von 52

1

When using a(n) ____ join, only rows that meet the given criteria are returned.

Wähle eine der folgenden:

  • full

  • inner

  • outer

  • set

Erklärung

Frage 15 von 52

1

What is the syntax for a left outer join?

Wähle eine der folgenden:

  • SELECT column-list
    FROM table1 OUTER JOIN table2 LEFT
    WHERE join-condition

  • SELECT column-list
    FROM table1 LEFT [OUTER] JOIN table2
    ON join-condition

  • SELECT column-list
    WHERE LEFT table1 = table 2

  • SELECT column-list
    FROM table1 LEFT table2 [JOIN]
    WHERE join-condition

Erklärung

Frage 16 von 52

1

In subquery terminology, the first query in the SQL statement is known as the ____ query.

Wähle eine der folgenden:

  • outer

  • left

  • inner

  • base

Erklärung

Frage 17 von 52

1

In a subquery, which query is executed first?

Wähle eine der folgenden:

  • Leftmost

  • Rightmost

  • Innermost

  • Outermost

Erklärung

Frage 18 von 52

1

Creating the conceptual design, selecting DBMS software, creating the logical design, and creating the physical design are part of the ____ phase.

Wähle eine der folgenden:

  • database initial study

  • database design

  • implementation and loading

  • testing and evaluation

Erklärung

Frage 19 von 52

1

Which of the conceptual design steps defines entities, attributes, and relationships?

Wähle eine der folgenden:

  • Database analysis and requirements

  • Entity relationship modeling and normalization

  • Data model verification

  • Distributed database design

Erklärung

Frage 20 von 52

1

What is the primary objective of database design?

Wähle eine der folgenden:

  • To create the most efficient database possible

  • To create complete, normalized, non-redundant, and fully integrated conceptual, logical, and physical database models

  • To create the fastest queries

  • To be able to add data quickly

Erklärung

Frage 21 von 52

1

The most common algorithms for concurrency control are locks, ____ stamping, and optimistic methods.

Wähle eine der folgenden:

  • date

  • time

  • hour

  • minute

Erklärung

Frage 22 von 52

1

____ requires that all operations of a transaction be completed.

Wähle eine der folgenden:

  • Specificity

  • Atomicity

  • Durability

  • Time stamping

Erklärung

Frage 23 von 52

1

The ____ establishes the order in which the operations within concurrent transactions are executed.

Wähle eine der folgenden:

  • transaction log

  • timer

  • lock manager

  • scheduler

Erklärung

Frage 24 von 52

1

When is the implicit beginning of a transaction?

Wähle eine der folgenden:

  • When the database is started

  • When a table is accessed for the first time

  • When the first SQL statement is encountered

  • When the COMMIT command is issued

Erklärung

Frage 25 von 52

1

A(n) ____ phase in a two-phase lock is when a transaction releases all locks and cannot obtain any new lock.

Wähle eine der folgenden:

  • growing

  • shrinking

  • locking

  • unlocking

Erklärung

Frage 26 von 52

1

What is a consistent database?

Wähle eine der folgenden:

  • One in which all tables have foreign keys

  • One in which all data integrity constraints are satisfied

  • One in which all tables are normalized

  • One in which all SQL statements only update one table at a time

Erklärung

Frage 27 von 52

1

A transaction acquires a ____ prior to data access.

Wähle eine der folgenden:

  • grain

  • timestamp

  • lock

  • key

Erklärung

Frage 28 von 52

1

Changes are permanently applied to the database during the ____ phase of a transaction.

Wähle eine der folgenden:

  • commit

  • write

  • input

  • output

Erklärung

Frage 29 von 52

1

The phenomenon of ____ occurs when two transactions, T1 and T2, are executed concurrently and the first transaction (T1) is rolled back after the second transaction (T2) has already accessed the uncommitted data—thus violating the isolation property of transactions.

Wähle eine der folgenden:

  • lost updates

  • uncommitted data

  • transaction failure

  • inconsistent retrieval

Erklärung

Frage 30 von 52

1

____ occur when a transaction calculates some summary (aggregate) functions over a set of data while other transactions are updating the data.

Wähle eine der folgenden:

  • Lost updates

  • Uncommitted data

  • Transaction failures

  • Inconsistent retrievals

Erklärung

Frage 31 von 52

1

The scheduler facilitates data ____ to ensure that two transactions do not update the same data element at the same time.

Wähle eine der folgenden:

  • durability

  • isolation

  • atomicity

  • serializability

Erklärung

Frage 32 von 52

1

Which is not a DML statement?

Wähle eine der folgenden:

  • CREATE TABLE

  • SELECT

  • INSERT

  • DELETE

Erklärung

Frage 33 von 52

1

What feature is a DDBMS disadvantage?

Wähle eine der folgenden:

  • Data is located near the “greatest demand” site

  • Growth facilitation

  • Reduced operating cost

  • Lack of standards

Erklärung

Frage 34 von 52

1

What feature is a DDBMS advantage?

Wähle eine der folgenden:

  • Greater difficulty in managing the data environment

  • Less danger of a single-point failure

  • Increased training cost

  • Complexity of management and control

Erklärung

Frage 35 von 52

1

____ distributed database systems integrate different types of centralized DBMSs over a network.

Wähle eine der folgenden:

  • Homogeneous

  • Heterogeneous

  • Fully homogeneous

  • Fully heterogeneous

Erklärung

Frage 36 von 52

1

____ transparency allows a transaction to update data at several network sites.

Wähle eine der folgenden:

  • Transaction

  • Distribution

  • Failure

  • Performance

Erklärung

Frage 37 von 52

1

____ transparency ensures that the system will continue to operate in the event of a node failure.

Wähle eine der folgenden:

  • Transaction

  • Distribution

  • Failure

  • Performance

Erklärung

Frage 38 von 52

1

The ____ contains the description of the entire database as seen by the database administrator.

Wähle eine der folgenden:

  • distributed global dictionary

  • distributed data dictionary

  • distributed global schema

  • distributed data schema

Erklärung

Frage 39 von 52

1

____ query optimization means that the DDBMS finds the most cost-effective access path without user intervention.

Wähle eine der folgenden:

  • Static

  • Dynamic

  • Automatic

  • Commit

Erklärung

Frage 40 von 52

1

____ query optimization takes place at execution time.

Wähle eine der folgenden:

  • Automatic

  • Static

  • Manual

  • Dynamic

Erklärung

Frage 41 von 52

1

A ____ based query optimization algorithm uses statistical information about the database.

Wähle eine der folgenden:

  • statistically

  • dynamic

  • rule

  • manual

Erklärung

Frage 42 von 52

1

Data ____ refers to the storage of data copies at multiple sites served by a computer network.

Wähle eine der folgenden:

  • replication

  • fragmentation

  • persistence

  • optimization

Erklärung

Frage 43 von 52

1

To provide better performance, some OLAP systems merge the data warehouse and data mart approaches by storing small extracts of the data warehouse at end user ____.

Wähle eine der folgenden:

  • workstations

  • queries

  • schemas

  • servers

Erklärung

Frage 44 von 52

1

____ makes a copy of a table and places it in a different location, to improve access time.

Wähle eine der folgenden:

  • Periodicity

  • Aggregation

  • Partitioning

  • Replication

Erklärung

Frage 45 von 52

1

The ____ schema creates the near equivalent of a multidimensional database schema from the existing relational database.

Wähle eine der folgenden:

  • star

  • square

  • OLAP

  • ROLAP

Erklärung

Frage 46 von 52

1

Using multidimensional jargon, the ability to focus on slices of the cube to perform a more detailed analysis is known as ____.

Wähle eine der folgenden:

  • star cuts

  • slice and dice

  • microscoping

  • TPL processing

Erklärung

Frage 47 von 52

1

A ____ is a uniquely identifiable object that allows a given person to log on to the database.

Wähle eine der folgenden:

  • user

  • role

  • profile

  • manager

Erklärung

Frage 48 von 52

1

Which DDL statement should be used to enforce referential integrity?

Wähle eine der folgenden:

  • CREATE TRIGGER AFTER GRANT

  • CREATE TRIGGER BEFORE UPDATE

  • CREATE TRIGGER BEFORE DROP

  • CREATE TRIGGER AFTER SELECT

Erklärung

Frage 49 von 52

1

Use the given code to answer the following question:

SELECT branchNo, COUNT(staffNo) AS myCount, SUM (salary) AS mySum
FROM staff,
GROUP BY branchNo
ORDER By branchNo;

What does this code do?

Wähle eine der folgenden:

  • Orders the staff table by the ascending order of branchNo

  • Orders the staff by ascending order of salary

  • Finds the number of staff and the sum of their salaries in each branch

  • Finds the total number of branches

Erklärung

Frage 50 von 52

1

Use the give DDL statement to answer the following question:
CREATE ASSERTION PhysicianNotOverbooked
CHECK (NOT EXISTS (SELECT physician_number
FROM scheduled_exams
GROUP By physician_number
HAVING COUNT (*) > 20));

Which action is this statement performing?

Wähle eine der folgenden:

  • Creating a trigger

  • Creating a stored procedure

  • Creating an index

  • Creating a constraint

Erklärung

Frage 51 von 52

1

Which DCL Command gives Manager the privilege to SELECT on column AccountBalance of the table Customer?

Wähle eine der folgenden:

  • GRANT SELECT (Customer) ON AccountBalance TO Manager;

  • GRANT SELECT (AccountBalance) ON Customer TO Manager;

  • PERMIT Manager SELECT ON Customer (AccountBalance);

  • ALLOW Manager SELECT AccountBalance FROM Customer;

Erklärung

Frage 52 von 52

1

Which statement produces a PL/SQL stored procedure?

Wähle eine der folgenden:

  • INSERT OR SET PROCEDURE ProcessReport AS
    BEGIN SELECT * FROM sales END

  • CREATE OR REPLACE PROCEDURE ProcessReport AS
    BEGIN SELECT * FROM sales END

  • ADD OR UPDATE PROCEDURE ProcessReport AS
    BEGIN SELECT * FROM sales END

  • INSERT OR UPDATE PROCEDURE ProcessReport AS
    BEGIN SELECT * FROM sales END

Erklärung