An XML document conforms to the following DTD
!ELEMENT root (item*)>
«!ELEMENT item (A*,B,C?)>
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Write a query to display the document without showing any C element.
The police data has the following format for the person ‘John’
driver (licNo, name, addr, photo, offence) #licNo=Driver’s license number.
a1 1jpg speeding
while the passport data in another database also has a person called ‘John’
passport(ppNo, name, addr, photo)
#ppNo=Passport number.
Discuss the the options that can be used to confirm a match of the two
Distributed relational databases use vertical and horizontal partitions to
distribute data but noSQL systems like Hadoop and Mongodb often use hash
to distribute data.
Explain the reasons for the practice.
Given the table
tutor(name, addr, program, wkours); PK=name
and a view
people(name, addr)
write a trigger to prevent any tuple in tutor from having a name in people. You
must use ‘before’ trigger plus an exception mechanism.
A bus company would like to analyze the reasons for bus delays. The delay is measured in minutes at each stop.
(a) Design a star schema for the analysis. This design is a list of table schemas with the fact table first and then the dimension tables. Show surrogate FKs right below the fact table and surrogate keys right
below their dimensional tables.
Format of the presentation is:
Delay (attri attr2 attr3 .…. delayminutes)
FK: attri references table2(attri)
FK: attr2 references table3(attr)
DimTable1 (attri, attr2, ..)
(b) Design 3 tuples of data for the fact table, and design corresponding data for the dimension tables.
Note: The number of dimension tables is proportional to your mark and the maximal number of dimension tables is limited to 5, and each dimension table must have 5 or more attributes (including 1 identity
and 1 key attributes). Data among the tables must be logically linked.
The format of your presentation is below
Delay (attri attr2 attr3 … delayminutes)
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