DOT NET Interview Questions - DotNetSpider

lstdata.DataSource = objDataSet.Tables("Table1").DefaultView
In order to refer “Table1” DataTable , use Tables collection of DataSet and the Defaultview
object will give you the necessary output.
(B) How can we add relation’s between table in a DataSet ?
Dim objRelation As DataRelation
objRelation=New
DataRelation("CustomerAddresses",objDataSet.Tables("Customer").Columns("Custid")
,objDataSet.Tables("Addresses").Columns("Custid_fk"))
objDataSet.Relations.Add(objRelation)
Relation’s can be added between “DataTable” object’s using the “DataRelation”
object.Above sample code is trying to build a relationship between “Customer” and
“Addresses” “Datatable” using “CustomerAddresses” “DataRelation” object.
(B) What’s the use of CommandBuilder ?
CommandBuilder builds “Parameter” objects automatically.Below is a simple code which
uses commandbuilder to load its parameter object’s.
Dim pobjCommandBuilder As New OleDbCommandBuilder(pobjDataAdapter)
pobjCommandBuilder.DeriveParameters(pobjCommand)
Be careful while using “DeriveParameters” method as it needs a extra trip to the Datastore
which can be very inefficient.
(B) What’s difference between “Optimistic” and
“Pessimistic” locking ?
In pessimistic locking when user wants to update data it locks the record and till then no
one can update data.Other user’s can only view the data when there is pessimistic locking.
In optimistic locking multiple user’s can open the same record for updating , thus increase
maximum concurrency.Record is only locked when updating the record.This is the most
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