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0

The database is distributed across the hotel chain.
Describe three different approaches to the distribution of databases.

One mark for method, one for expansion:
 partitioned between sites / hotels (1) each separate hotel in the chain holds data on that particular sit(1)
 partitioned horizontally(1) database split between
sites/departments by fields (1)
 partitioned vertically (1) database split between sites/departments by fields (1)
 database duplicated between sites (1) a full copy
indexes are held at each hotel (1)
 one central database (1) relevant/site specific indexes are held at each hotel (1)

1

The Mountain Rescue team is part of a regional Mountain Rescue Organisation which holds details of all its members in a regional database. This database needs to be distributed to each Mountain Rescue Team.

Explain an advantage to the regional Mountain Rescue Organisation of using a central database with remote local indexes.

 storage is only required at the central location for the centralised database (1) the local indexes stored at each site take up far less memory (1)
 queries are processed locally(1) this speeds up searches as only the required data is retrieved from the central location (1)
 less data traffic than complete centralisation (1) as only data is sent and not the additional information /forms/reports structure (1)  increased security (1) only central database needs increased
security as that is where the data is stored (1
 integrity of data not compromised (1) as it is stored in only one
location and one database to update (1)
 centralised back-up of data (1) management backup easier as one person’s responsibility (1)

2

The Mountain Rescue team is part of a regional Mountain Rescue Organisation which holds details of all its members in a regional database. This database needs to be distributed to each Mountain Rescue Team.
Explain how the regional Mountain Rescue Organisation could make use of vertical partitioning.

One mark for point (max 2), one for expansion (max 3)
 only certain people see certain fields (1) financial matters not
revealed to all (1)
 to conform to the law/DPA (1) keeping personal information private (1)
 reduces amount of data being sent between locations (1) in order to speed up data transfer (1) allowing faster reaction time (1)
meaning rescue reaches emergency quicker (1)

3

The dental surgery’s custom-written patient database system is to be modified for use by both
parts of the surgery.

Define what is meant by vertical partitioning of a database.

Data is separated based on fields.

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