Pairwise Testing Cases sets division

There is an explaination about pairwise testing Here.

 

Actually, the testcases designed with pairwise can be different.  I do not won't to explain the algorithm behind how to get a pairwise test cases. I just give an example on how to get all the sets of test cases.

 

Give we have 3 fields with values:

Field 1	Field 2	Field3
1	a	A
2	b	B
3	c	C

 

 

If we use 2 as the factor. Then below are 3 sets of testcases we can get:

Field1	Field2	Field3
1	a	A
1	b	B
1	c	C
2	a	C
2	b	B
2	c	A
3	a	B
3	b	C
3	c	A

 

 

 

Field1	Field2	Field3
3	a	A
1	b	A
2	c	A
2	a	B
3	b	B
1	c	B
1	a	C
2	b	C
3	c	C

 

Field1	Field2	Field3
2	a	A
1	a	B
3	a	C
3	b	C
2	b	B
1	b	A
1	c	B
3	c	C
2	c	A

 

 

These 3 sets of test cases have the same test coverage. They are equal in test effect if we do not consider the weight.

 

If we union all these 3 sets of cases, then we get the full coverage of the test.