Matakuliah
Tahun
Versi
: M0174/OBJECT ORIENTED DATABASE
: 2005
: 1/0
Pertemuan 10
The Manipulative part of the object
data model (Lanjutan bagian 1)
1
Learning Outcomes
Pada akhir pertemuan ini, diharapkan mahasiswa
akan mampu :
• Mahasiswa dapat Menjelaskan penerapan
penggunaan dan konsep data model dari
generasi teknologi database (C2)
2
Outline Materi
• Pick and mix operations
• Object processing operators
• Boolean operators
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Pick and mix operations
• Restrict
– Restrict is a unary operator (it operates on
just one object). This operator is sometime
call “select”, but here we used the name
restrict so as to avoid confusion with select
operation in OQL.
– This operator is used to define a set object
which contain object for which some condition
is true.
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Pick and mix operations
• Example
Restrict product where color = ‘Black’
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Pick and mix operations
• Union
– Is a binary operator (it takes two objects as
operands).
– Union of two set object is a set object which
contains all off the objects contained in one or
both of the two operand set objects.
• Example
Retail_Customer Union [Customer]
Trade_Customer
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Pick and mix operations
• Intersect
– Intersect like union operators upon two set
objects.
– The intersection of two set objects contains
object which occur in both of them.
• Example
Retail_Customer Intersect [Customer]
Trade_Customer
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Pick and mix operations
• Difference (minus)
– This operator like intersect and union,
operators upon two set objects.
– Difference define a set object which contains
objects which occur in the first of the operand
set objects, but not in the second.
• Example
Retail_Customer Minus [Customer]
Trade_Customer
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Object processing operators
• Apply
– Is used to process the objects in a set by
applying to each of them a specific operation.
• Fold
– This operator like Apply, applies an operation
to each object in a set, but also applies a
second operation to resulting object so as to
combine them into a single object
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Object processing operators
• Join
– A join operation matches object within
difference set object, and then applies a
specified function to each matching pair.
• Tuple_Join
– The tuple_join of two set objects R and S
using the matching function P.
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Object processing operators
• Outer_Join
– The outer_Join combines objects taken from two
operand set object and uses three functions. The first
processes pair of matching objects, the second
processes unmatched objects from the first operand,
and the third processes unmatched object from the
second operand.
• Least_Fixed_Point
– This operator retrieves information by repeatedly
applying a specified function until no further
information can be granted.
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Boolean operators
• Exists
– This operator returns true if there exists within
a set object an object for which a specified
Boolean condition evaluates to true, otherwise
it returns false.
• Forall
– This operator returns true if a specified
Boolean expression returns true for all objects
contain in the operand set object, otherwise
the expression returns false.
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Boolean operators
• Member
– The member operator returns true if a
specified object is contained with a setobjects, otherwise it returns false.
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SUMMARY
• The pick and mix operator upon set
objects are RESTRICT, UNION,
INTERSECT, DIFFERENCE, CHOOSE,
GROUP, AND ELIMINATE_DUPLICATES
• Object processing operators include
APPLY, FOLD, JOIN, and LEAST_FIXED
POINT
• Boolean operators include EXIST,
FORALL, and MEMBER
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