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Q) Explain the architecture of ResultSet?



A)
->A Resultset is divided into 3 parts.

1) Zero record area
2) Records area
3) No record area

->when the resultSet is open a logical pointer known as “cursor” points to zero record area.
->when cursor is pointing to zero record or no record area we should not process the record.     We get SQL Exception.
->java.sql.ResultSet object has around 15 methods to deal with cursor.
->next() method is most frequently used method.
->when next() method is called on ResultSet object, 2 things happen in the background.
  1) Cursor is moved in forward direction by one record area.
  2) It returns true if record exists there otherwise false.
->To process the record, i.e. to retrieve the record each column value of the record (row) of the ResultSet object, getxxx() methods are available. These methods take column member in the ResultSet records as argument and return the column value. Relational table column type influences the kind of getxxx method we need to call on ResultSet object.

Some example for getxxx() methods :
getFloat()
getString()
getInt()
getBytes()

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