Mn relationships cannot be implemented as such in the

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M:N relationships cannot be implemented as such in the relational model. Later in this section, you will see how any M:N relationship can be changed into two 1:M relationshipsCardinality - denotes how many instance of one object are related to instances of another object
Modality - denotes an instance of a specific entity is optional or mandatory in arelationship*In other words, modality refers to the minimum number of times an instance of an entity can be associated with an instance in a related entity while cardinality refers to the maximum number of times this relationship may occur.INDEX - is an orderly arrangement used to logically access rows in a tableUNION is denoted by U-It combines tables excluding duplicate rowsIntersect is denoted by N-It returns only the rows that appear in both tablesDIFFERENCE is denoted by --Yields all rows in one table that are not found in the other tablePRODUCT is denoted by x-Yields all possible pairs of rows from two tablesDIVIDE-Used to see if one set of data is associated with all values of data in another set of dataJOIN -Intelligently combine two or more tables that are linked by common attributesNatural JOIN-Links tables by selecting only the rows with common values in their common attributesINNER JOIN -Only returns matched records from the tables that are being joined. OUTER JOIN basically is an inner join plus
-Matched pairs are retained AND any unmatched values in the other table would be left as nullLEFT OUTER JOIN -yields all the rows in the first table, including those that do not match a value in the other tableRIGHT OUTER JOIN-

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