A union, intersection or difference can only be performed between two relations if they are type compatible. What is meant by type compatibility? Give an...

A union, intersection or difference can only be performed between two relations if they are type compatible. What is meant by type compatibility? Give an example of two type compatible and two non type compatible relations?

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Two relations are type compatible if they have same set of attributes. Example of two type compatible relations is:
Men {, , }
Women {, , }

Example of two relations which are nontype compatible is:
Husband {, , }
Wife {, , }

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Mwalimu Bonface answered the question on March 1, 2018 at 10:22

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