Page 175 - Artificial Intellegence_v2.0_Class_11
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Union Operation
The union operation combines two or more relations (tables). The union operation is a binary operation. The resultant
relation of the union operation contains tuples that are in either of the relation or in both relations. The duplicate
tuples are eliminated. The symbol denotes the union operation.
Before applying the union operation, the two relations must satisfy these situations:
• Both the relations are of the same degree.
• The domain of the attributes of both the relations (pool of data containing values) are the same.
Student Student 1
Rollno Name Marks Rollno Name Marks
100 Prakash 256 101 Vivek 256
102 Sudha 210
103 Punit 269 103 Punit 269
105 Jimmy 210 104 Kumar 287
106 John 276
106 John 276
If we perform union operation on the above two tables: σ (Student Student1) we get the following result:
Result of the Union Operation
Rollno Name Marks
100 Prakash 256
101 Vivek 256
102 Sudha 210
103 Punit 269
104 Kumar 287
105 Jimmy 210
106 John 276
Intersection Operation
The intersection operation is also a binary operation. The intersection operation yields the common tuples from the
two tables. Consider the following tables:
Student Student 1
Rollno Name Marks Rollno Name Marks
100 Prakash 256
102 Sudha 210 101 Vivek 256
103 Punit 269 103 Punit 269
105 Jimmy 210 104 Kumar 287
106 John 276
106 John 276
The result produced by the intersection operation (Student ∩ Student1) is shown as:
Result of the Intersection Operation
Rollno Name Marks
103 Punit 269
106 John 276
Maths for AI 173

