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edit approved Oct 4, 2015 at 13:50
H. Pauwelyn
edit approved Oct 4, 2015 at 13:50
H. Pauwelyn
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I have a question regarding the resulting attributes in the cross product of two relations in relational algebra... 

Generally, the cross product will result in a relation whoswhose attributes is the sum of all the attributes, So number of attributes in R1xR2R1 x R2 will be attributes in R1 + R2R1 + R2, so R1(a,b,c) x R2(d,e,f) --> R(a,b,c,d,e,f) R1(a, b, c) x R2(d, e, f) → R(a, b, c, d ,e ,f)... but

But, what happens if R1R1 and R2R2 have common attributes? (attributes of the same name)(attributes of the same name)? since a relation can not have duplicate attributes... so what would happen in the case R1(a,b,c) X R2(a,e,f)R1(a, b, c) X R2(a, e, f)? thanks...

I have a question regarding the resulting attributes in the cross product of two relations in relational algebra... Generally, the cross product will result in a relation whos attributes is the sum of all the attributes, So number of attributes in R1xR2 will be attributes in R1 + R2, so R1(a,b,c) x R2(d,e,f) --> R(a,b,c,d,e,f) ... but, what happens if R1 and R2 have common attributes? (attributes of the same name)? since a relation can not have duplicate attributes... so what would happen in the case R1(a,b,c) X R2(a,e,f)? thanks...

I have a question regarding the resulting attributes in the cross product of two relations in relational algebra... 

Generally, the cross product will result in a relation whose attributes is the sum of all the attributes, So number of attributes in R1 x R2 will be attributes in R1 + R2, so R1(a, b, c) x R2(d, e, f) → R(a, b, c, d ,e ,f)...

But, what happens if R1 and R2 have common attributes (attributes of the same name)? since a relation can not have duplicate attributes... so what would happen in the case R1(a, b, c) X R2(a, e, f)? thanks...

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Daniel Valland
Daniel Valland
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Attributes in relation after cross product

I have a question regarding the resulting attributes in the cross product of two relations in relational algebra... Generally, the cross product will result in a relation whos attributes is the sum of all the attributes, So number of attributes in R1xR2 will be attributes in R1 + R2, so R1(a,b,c) x R2(d,e,f) --> R(a,b,c,d,e,f) ... but, what happens if R1 and R2 have common attributes? (attributes of the same name)? since a relation can not have duplicate attributes... so what would happen in the case R1(a,b,c) X R2(a,e,f)? thanks...