What is Primary key and foreign key? Give an example
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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
| Is This Answer Correct ? | 17 Yes | 2 No |
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
| Is This Answer Correct ? | 4 Yes | 1 No |
Answer / aaaaaaaaaaaaa
Primary key is a primary key that is an attribute.
| Is This Answer Correct ? | 4 Yes | 4 No |
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.
| Is This Answer Correct ? | 0 Yes | 0 No |
What is user-defined inline table-valued function?
if we have a column (Key) in a table. and values of that column is Key 1 1 1 2 2 3 3 4 4 5 5 5 and we want to show the data after query..like.. 1(3) 2(3) 3(2) 4(2) 5(3) how many times a single term comes..
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