Database Reference
In-Depth Information
Q&A
18
Question: To check your understanding of the relationship between publishers and books, answer the follow-
ing questions: Who published Jazz? Which books did Jove Publications publish?
Answer: Plume published Jazz. In the row in the Topic table for Jazz (see Figure 1-17), find the publisher
code PL. Examining the Publisher table (see Figure 1-15), you see that PL is the code assigned to Plume.
Jove Publications published The Edge, When Rabbit Howls, and Slay Ride. To find the topics published
by Jove Publications, find its code (JP) in the Publisher table. Next, find all rows in the topic table for which
the publisher code is JP.
The table named Wrote, shown below in Figure 1-18, is used to relate books and authors. The Sequence
field indicates the order in which the authors of a particular book are listed on the cover. The table named
Copy, shown on the next three pages, is used to indicate the detailed facts about each copy of a particular
book currently on hand at a particular branch of Henry Books. The first row, for example, indicates that
there is a copy of the topic with the topic code 0180 available at branch 1, the topic
'
s quality is excellent, and
the topic
'
s price is $7.19.
Wrote
Wrote
(continued)
BookCode
AuthorNum
Sequence
BookCode
AuthorNum
Sequence
0180
3
1
5163
20
1
0189
5
1
5790
10
1
0200
18
1
6128
1
1
0378
11
1
6328
14
1
079X
4
1
669X
7
1
0808
4
1
6908
16
1
1351
6
1
7405
20
1
1382
23
2
7443
15
1
1382
25
1
7559
18
1
138X
1
1
8092
12
1
2226
15
1
8720
8
1
2281
9
2
9611
5
2
2281
19
1
9611
6
1
2766
20
1
9627
1
1
2908
17
1
9701
20
1
3350
2
1
9882
4
1
3743
16
1
9883
16
1
3906
24
1
9931
13
1
FIGURE 1-18
Sample data that relates books to authors and books to branches for Henry Books
(continued)
