How are 1:1, 1:N and N:M relationships handled in Microsoft ...

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How are 1:1, 1:N and N:M relationships handled in Microsoft Access?
 
  What will be an ideal response?

Question 2

Discuss SQL data types.
 
  What will be an ideal response?

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Answer to Question 1

By default, when Microsoft Access creates a relationship between two tables, it creates a 1:N relationship. N:M relationships are created in Microsoft Access, as in all other DBMS products, as two 1:N relationships linking the two tables (based on the original two entities) through an intersection table. As far as Microsoft Access is concerned, there are no N:M relationships To create a 1:1 relationship between two tables in Microsoft Access, the Indexed property of the foreign key column in the table containing the foreign key must be set to Yes (No Duplicates) before the relationship is created. With the property set, the relation is automatically created as a 1:1 relationship.

Answer to Question 2

Common examples of standard SQL data types are Char, VarChar, Integer, and Numeric. The Char data type is for fixed-length character data. VarChar is for variable-length character data. Integer is for numeric data that are whole numbers only. Numeric is for numeric data that may include decimals. Char, VarChar, and Numeric must be qualified by a length specification to indicate the amount of storage space to be allocated for each data item. For example, Char(10 ) indicates fixed-length character data that is always stored as 10 characters.