All categories

3 years ago

For each of the descriptions below, perform the following tasks:

Computers and Technology

1 answer:

Zigmanuir [339]3 years ago

8 0

Answer:

attached below in the explanation and the diagrams attached

Explanation:

question

i) identify the degree and cardinality of the relationship

ii) Express the entities and the relationships with attributes in each description graphically with an E-R diagram 

A)

i) The degree and cardinality of the relationship

The entities PIANO, MODEL and DESIGNER have a degree of two i.e. Binary relationship
The cardinality of the entities PIANO, MODEL and DESIGNER have a relationship of ONE-to-many

ii) description graphically with an E-R diagram

The E-R diagrams show that The degree of the relationship for the entities PIANO, MODEL, and DESIGNER is two(2). and also shows that there is a One-to-Many cardinality available in the entities PIANO, MODEL, and DESIGNER

E-R diagram Attached below

B)

i) The degree and cardinality of the relationship

entities PIANO and Technician have a degree of two ( 2 ) ; i.e. a Binary relationship
The cardinality of the entities PIANO, and TECHNICIAN have a relationship of Many-to-Many.

ii) Graphical description with an E-R diagram

The diagram describes/ shows that, entities PIANO and Technician have a degree of two ( 2 ) ; i.e. a Binary relationship and also The cardinality of the entities PIANO, and TECHNICIAN have a relationship of Many-to-Many.

E-R diagram attached below

C)

i) Degree and cardinality of the entity Technician

The entity TECHNICIAN has a degree one, i.e. a unary relationship.

The cardinality of the entity TECHNICIAN have the relationship of One-to-Many.

ii) E-R diagram attached below

D) 

i) Degree and cardinality of the relationship

The entities TABLET TYPE and PROCESSOR TYPE have a degree of two(2) , i.e. a binary relationship

The cardinality these entities TABLET TYPE, and PROCESSOR TYPE have is a Many-to-Many relationship

ii) E-R diagram attached for TABLET TYPE, PROCESSOR TYPE is attached below

E)

i) Degree and cardinality of the relationship

The entities TABLET TYPE, TABLET COMPUTER, and CUSTOMER have a degree of two(2) ; i.e. a binary relationship.

The cardinality these entities TABLET TYPE, TABLET COMPUTER, and CUSTOMER have is a One-to-Many relationship

also the shipment to the customer is multiple hence the relationship can be said to be Many-to-Many relationship

also The attribute Shipping Date will become an attribute of that M: M relationship.

ii) The E-R diagram for TABLET TYPE, TABLET COMPUTER, CUSTOMER is attached below

F)

i) Degree and cardinality of the relationship between TABLET TYPE, TECHNICIAN

The entities TABLET TYPE, and TECHNICIAN have a degree of two(2); i.e. a binary relationship.

The cardinality these entities TABLET TYPE, and TECHNICIAN have is a Many-to-Many relationship

ii) E-R diagram attached below

You might be interested in

What are the business drivers of cloud computing?(Choose all that apply.)

Xelga [282]

Answer: The applicable answers are b, c, and d.

Explanation:

When a company decides to hire the services of a cloud computing service provider, instead of investing in purchasing the resources needed in order to match its needs, as the cloud model is based on the concept "pay as you go", it allows to maximize the costs efficiency, and at the same time, gives the company the choice to define what type of steps are needed to grow, and when it is advisable to go beyond.

Finally, as it is possible to expand the services hired on the fly very easily, it is a very good way to be sure that it will never ran out of resources, no matter that future needs could be.

Actually, the only answer that is wrong is a) because it happens just the opposite: Cloud services allow to decrease time to market substantially.

7 0

3 years ago

Imagine that you only used assignment statements for the design of the seven-segment display decoder. How would you obtain the B

Basile [38]

Answer:

Please see the attached file for the complete answer.

Explanation:

Download pdf

6 0

3 years ago

I need the SQL statements for these questions:

zimovet [89]

Answer:

Explanation:

/* From the information provided, For now will consider the name of table as TRIPGUIDES*/

/*In all the answers below, the syntax is based on Oracle SQL. In case of usage of other database queries, answer may vary to some extent*/

Select R.Reservation_ID, R.Trip_ID , C.Customer_Num,C.Last_Name from Reservation R, Customer C where C.Customer_Num=R.Customer_Num ORDER BY C.Last_Name

/*idea is to select the join the two tables by comparing customer_id field in two tables as it is the only field which is common and then print the desired result later ordering by last name to get the results in sorted order*/

Select R.Reservation_ID, R.Trip_ID , R.NUM_PERSONS from Reservation R, Customer C where C.Customer_Num=R.Customer_Num and C.LAST_NAME='Goff' and C.FIRST_NAME='Ryan'

/*Here, the explaination will be similar to the first query. Choose the desired columns from the tables, and join the two tables by equating the common field

Select T.TRIP_NAME from TRIP T,GUIDE G,TRIPGUIDES TG where T.TRIP_ID=TG.TRIP_ID and TG.GUIDE_NUM=G.GUIDE_NUM and G.LAST_NAME='Abrams' and G.FIRST_NAME='Miles'

Here,we choose three tables TRIP,GUIDE and TRIPGUIDES. Here we selected those trips where we have guides as Miles Abrms in the GUIDES table and equated Trip_id from TRIPGUIDES to TRIP.TRIP_Name so that can have the desired results

Select T.TRIP_NAME

from TRIP T,TRIPGUIDES TG ,G.GUIDE

where T.TRIP_ID=TG.TRIP_ID and T.TYPE='Biking' and TG.GUIDE_NUM=G.GUIDE_NUM and G.LAST_NAME='Boyers' and G.FIRST_NAME='Rita'

In the above question, we first selected the trip name from trip table. To put the condition we first make sure that all the three tables are connected properly. In order to do so, we have equated Guide_nums in guide and tripguides. and also equated trip_id in tripguides and trip. Then we equated names from guide tables and type from trip table for the desired results.

SELECT C.LAST_NAME , T.TRIP_NAME , T.START_LOCATION FROM CUSTOMER C, TRIP T, RESERVATION R WHERE R.TRIP_DATE='2016-07-23' AND T.TRIP_ID=R.TRIP_ID AND C.CUSTOMER_NUM=R.CUSTOMER_NUM

The explaination for this one will be equivalent to the previous question where we just equated the desired columns where we equiated the desired columns in respective fields and also equated the common entities like trip ids and customer ids so that can join tables properly

/*The comparison of dates in SQL depends on the format in which they are stored. In the upper case if the

dates are stored in the format as YYYY-MM-DD, then the above query mentioned will work. In case dates are stored in the form of a string then the following query will work.

SELECT C.LAST_NAME , T.TRIP_NAME , T.START_LOCATION FROM CUSTOMER C, TRIP T, RESERVATION R WHERE R.TRIP_DATE='7/23/2016' AND T.TRIP_ID=R.TRIP_ID AND C.CUSTOMER_NUM=R.CUSTOMER_NUM

Select R.RESERVATION_ID, R.TRIP_ID,R.TRIP_DATE FROM RESERVATION R WHERE R.TRIP_ID IN

{SELECT TRIP_ID FROM TRIP T WHERE STATE='ME'}

In the above question, we firstly extracted all the trip id's which are having locations as maine. Now we have the list of all the trip_id's that have location maine. Now we just need to extract the reservation ids for the same which can be trivally done by simply using the in clause stating print all the tuples whose id's are there in the list of inner query. Remember, IN always checks in the set of values.

Select R.RESERVATION_ID, R.TRIP_ID,R.TRIP_DATE FROM RESERVATION WHERE

EXISTS {SELECT TRIP_ID FROM TRIP T WHERE STATE='ME' and R.TRIP_ID=T.TRIP_ID}

Unlike IN, Exist returns either true or false based on existance of any tuple in the condition provided. In the question above, firstly we checked for the possibilities if there is a trip in state ME and TRIP_IDs are common. Then we selected reservation ID, trip ID and Trip dates for all queries that returns true for inner query

SELECT G.LAST_NAME,G.FIRST_NAME FROM GUIDE WHERE G.GUIDE_NUM IN

{

SELECT DISTINCT TG.GUIDE_NUM FROM TRIPGUIDES TG WHERE TG.TRIPID IN {

SELECT T.TRIP_ID FROM TRIP T WHERE T.TYPE='Paddling'

}

We have used here double nested IN queries. Firstly we selected all the trips which had paddling type (from the inner most queries). Using the same, we get the list of guides,(basically got the list of guide_numbers) of all the guides eds which were on trips with trip id we got from the inner most queries. Now that we have all the guide_Nums that were on trip with type paddling, we can simply use the query select last name and first name of all the guides which are having guide nums in the list returned by middle query.

4 0

3 years ago

A voice engineer is setting up a Cisco 2951 Integrated Services Router with Cisco Unified Communications Manager Express. To ena

o-na [289]

Answer:

voice service voip

Explanation:

Voice over Internet Protocol feature allows users to make voice calls by making use of a broadband internet connection. The Voice engineer is setting up a Cisco 2951 Integrated Services Router with Cisco Unified Communications Manager Express, which happens to fall under broadband internet connection and hence the command the engineer will enter must be a voice service voip.

8 0

3 years ago

When selecting Internet research sources, you should verify that the source is _____ and _____.

Naddik [55]

Current and credible

7 0

3 years ago