Answer / vipin

Primary key which enforce the uniqueness in each row og table .
Foreign key win which the existing value in table must be there in other table .
diffrence is that PK does not allow Null Values anf FK allow null values

Answer / brajesh kumar srivastava

Primary key enforce uniqueness of column and deny to allow
null values to this column and enforce referential data
integrity constraint to other table column which is call
foreign key.
Foreign key column may contain null value

Answer / aaaaaaaaaaaaa

Primary key is a primary key that is an attribute.

Answer / alquama rizvi

MS-Access requires a special way of recognising every record of a table. For this you have to set or make a primary key. If you do not do so, MS-Access does this itself by adding a new field , serving as the primary key. A table may have only one primary key, although it may have more than one fields.

Write an SQL query if u want to select the data from one block which intern reflects in another block ? thanx,do reply

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