1.
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What is Ado.NET?
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ADO.NET is an
object-oriented set of libraries that allows you to interact with data
sources.
ADO.NET is a set of
classes that expose data access services to the .NET programmer.
ADO.NET is also a
part of the .NET Framework.
ADO.NET is used to
handle data access.
ADO.NET is entirely
based on XML.
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2.
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What are the two
fundamental objects in ADO.NET?
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There are two fundamental objects
in ADO.NET.
Datareader - connected architecture and Dataset - disconnected architecture. |
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3.
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What are the data
access namespaces in .NET?
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The
most common data access namespaces :
System.Data
System.Data.OleDb
System.Data.SQLClient
System.Data.SQLTypes
System.Data.XML
System.Data.LINQ
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4.
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What are major
difference between classic ADO and ADO.NET?
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In ADO the
in-memory representation of data is the recordset.A Recordset object is used
to hold a set of records from a database table.
In ADO.NET we have dataset.A DataSet is an in memory representation of data loaded from any data source. |
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5.
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What is the use of
connection object in ado.net?
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The ADO Connection Object is used
to create an open connection to a data source. Through this connection, you
can access and manipulate a database.
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6.
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What are the
benefits of ADO.NET?
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Scalability
Data Source
Independence
Interoperability
Strongly Typed Fields
Performance
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7.
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What are the parts
of ADO.NET?
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ADO.NET is divided into the
Dataset object for manipulating disconnected data and the .NET Data Providers
for communicating with backend data stores and the Dataset.
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8.
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Whate are different
types of Commands available with DataAdapter ?
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The
SqlDataAdapter has
SelectCommand
InsertCommand
DeleteCommand
UpdateCommand
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9.
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What is the
difference between an ADO.NET Dataset and an ADO Recordset?
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Dataset can fetch
source data from many tables at a time, for Recordset you can achieve the
same only using the SQL joins.
A DataSet can
represent an entire relational database in memory, complete with tables,
relations, and views, A Recordset can not.
A DataSet is designed
to work without any continues connection to the original data source;
Recordset maintains continues connection with the original data source.
DataSets have no
current record pointer, you can use For Each loops to move through the data.
Recordsets have pointers to move through them.
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10.
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What are the
parameters that control most of connection pooling behaviors?
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Connect Timeout
Max Pool Size
Min Pool Size
Pooling
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11.
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What is a DataSet?
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A DataSet is an in memory
representation of data loaded from any data source.
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12.
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What is a DataTable?
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A DataTable is a class in .NET
Framework and in simple words a DataTable object represents a table from a
database.
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13. |
What is the data
provider name to connect to Access database?
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Microsoft.Access
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14. |
Which namespaces are
used for data access?
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System.Data
System.Data.OleDB
System.Data.SQLClient
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15. |
What is difference
between dataset and datareader?
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DataReader provides
forward-only and read-only access to data, while the DataSet object can hold
more than one table (in other words more than one rowset) from the same data
source as well as the relationships between them.
Dataset is a
disconnected architecture while datareader is connected architecture.
Dataset can persist
contents while datareader can not persist contents, they are forward only.
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16. |
What are the major
components of data provider?
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The Connection object which provides a connection to
the database.
The Command object which is used to execute a
command.
The DataReader object which provides a forward–only,
read only, connected recordset.
The DataAdapter object which populates a
disconnected DataSet with data and performs update.
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17.
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What do you mean by
Dataset?
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A Dataset is a container where all
the rows fetched from a database table.
It is the job of DataAdapter to fill the Dataset with rows from the database. |
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18.
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What keyword is used
to accept a variable number of parameter in a method?
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Params.
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19. |
What are the types
of .Net data providers?
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The OLE DB.NET data
provider
The SQL Server.NET
data provider
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20. |
What are the
advantage of ADO.Net?
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Database Interactions
Are Performed Using Data Commands
Data Can Be Cached in
Datasets
Datasets Are
Independent of Data Sources
Data Is Persisted as
XML.
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21. |
What is the
difference between OLEDB Provider and SqlClient ?
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SQLClient .NET classes are highly
optimized for the .net / sqlserver combination and achieve optimal results.
The SqlClient data provider is fast. It's faster than the Oracle provider,
and faster than accessing database via the OleDb layer.
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22. |
What is the use of
Parameter Object?
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In ADO Parameter object provides
information about a single parameter used in a stored procedure or query.
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23. |
What is DataAdapter?
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DataSet contains the data from the
DataAdapter which is the bridge between the DataSet and Database. DataAdapter
provides the way to retrieve and save data between the DataSet and Database.
It accomplishes this by means of request to the SQL Commands made against the
database.
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24. |
What does ADO mean?
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ADO stands for ActiceX Data
Objects.It was introduced few years ago as a solution to accessing data that
can be found in various forms, not only over a LAN but over the internet. It
replaced the data access technologies RDO(Remote Data Objects) and DAO (Data
Access Objects).
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25. |
Name some ADO.NET
Objects?
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Connection Object
DataReader Object
Command Object
DataSet Object
DataAdapter Object
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26. |
What is the
DataTableCollection?
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An ADO.NET DataSet contains a
collection of zero or more tables represented by DataTable objects. The
DataTableCollection contains all the DataTable objects in a DataSet.
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27. |
What are the
benefits of ADO.NET?
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ADO.NET
offers several advantages over previous versions of ADO and over other data
access components. These benefits fall into the following categories:
Interoperability
Maintainability
Programmability
Performance
Scalability
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28. |
How to creating a
SqlConnection Object?
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SqlConnection conn = new
SqlConnection("Data Source=DatabaseServer;Initial Catalog=Northwind;User
ID=YourUserID;Password=YourPassword");
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29. |
How to creating a
SqlCommand Object?
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It takes a string parameter that
holds the command you want to execute and a reference to a SqlConnection
object.
SqlCommand cmd = new SqlCommand("select CategoryName from Categories", conn); |
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30. |
How to load multiple
tables into dataset?
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SqlDataAdapter da = new
SqlDataAdapter("Select * from Id; Select * from Salry", mycon);
da.Fill(ds); ds.Tables[0].TableName = "Id"; ds.Tables[1].TableName = "Salary"; |
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31.
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What is the
difference between SqlCommand and SqlCommandBuilder?
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SQLCommand is used to retrieve or
update the data from database.
SQLCommandBuilder object is used to build & execute SQL (DML) queries like select insert update& delete. |
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32.
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What is the use of
SqlCommandBuilder?
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SQL CommandBuilder object is used
to build & execute SQL (DML) queries like select insert update&
delete.
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33. |
How to copy the
database from one server to another server?
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The easiest way to copy a database
from one server to another is to back up the database from the source server
in the form of SQL script and execute the SQL script on the destination
server to recreate database and its respective tables.
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34.
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What is LINQ?
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LINQ is an acronym
for the Language Integrated Query and is a part of .NET framework.
It defines a set of
Standard Query Operators that enables us to query data in .NET
supported languages.
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35. |
Explain ADO.Net
Architecture?
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ADO.NET
provides the efficient way to manipulate the database. It contains the
following major components. 1. DataSet Object 2. Data Providers :
Connection Object
Command Object
DataReader Object
DataAdapter Object.
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31. |
What is the
difference between SqlCommand and SqlCommandBuilder?
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SQLCommand is used to retrieve or
update the data from database.
SQLCommandBuilder object is used to build & execute SQL (DML) queries like select insert update& delete. |
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32. |
What is the use of
SqlCommandBuilder?
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SQL CommandBuilder object is used
to build & execute SQL (DML) queries like select insert update&
delete.
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33.
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How to copy the
database from one server to another server?
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The easiest way to copy a database
from one server to another is to back up the database from the source server
in the form of SQL script and execute the SQL script on the destination
server to recreate database and its respective tables.
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·
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34. |
What is LINQ?
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LINQ is an acronym
for the Language Integrated Query and is a part of .NET framework.
It defines a set of
Standard Query Operators that enables us to query data in .NET
supported languages.
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35.
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Explain ADO.Net
Architecture?
|
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ADO.NET
provides the efficient way to manipulate the database. It contains the
following major components.
1.
DataSet Object 2. Data Providers :
Connection Object
Command Object
DataReader Object
DataAdapter Object.
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What is the difference between int and int32? |
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Both are same. System.Int32 is a
.NET class. Int is an alias name for System.Int32.
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37. |
What is the role of
the DataReader class in ADO.NET connections?
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It returns a read-only,
forward-only rowset from the data source. A DataReader provides fast access
when a forward-only sequential read is needed.
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38. |
What are advantages
and disadvantages of Microsoft-provided data provider classes in ADO.NET?
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SQLServer.NET data provider is
high-speed and robust, but requires SQL Server license purchased from
Microsoft. OLE-DB.NET is universal for accessing other sources, like Oracle,
DB2, Microsoft Access and Informix. OLE-DB.NET is a .NET layer on top of the
OLE layer, so it’s not as fastest and efficient as SqlServer.NET.
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39. |
What are acid
properties?
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Atomicity
Consistency
Isolation
Durability
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40. |
What is
DataRowCollection?
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Similar to DataTableCollection, to
represent each row in each Table we have DataRowCollection.
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41. |
What are basic
methods of Dataadapter?
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Fill
FillSchema
Update
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42. |
What are the various
methods provided by the dataset object to generate XML?
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ReadXML : Read’s a XML document in to Dataset.
GetXML : This is a function which returns the string containing XML document. WriteXML : This writes a XML data to disk. |
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43. |
What is DataSet
Object?
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Dataset is a disconnected,
in-memory representation of data. It can contain multiple data table from
different database.
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44. |
What is difference
between Optimistic and Pessimistic locking?
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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 users can open the same record for updating, thus increase maximum concurrency. Record is only locked when updating the record. |
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45. |
What is the role of
DataReader object?
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A DataReader object
provides forward only, read only access to a database.
The connection to the
database must be open while accessing data through DataReader object.
It loads only a
single row at a time in the memory.
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46. |
Which architecture
does datasets follow?
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Datasets follows the disconnected
data architecture.
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47. |
What is
Serialization?
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Serialization is the
process of persisting the state of an object after converting it into a
stream of bytes.
The object can be
persisted to a file, a database or memory.
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48. |
What is Execute Non
Query?
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The ExecuteNonQuery() is one of
the most frequently used method in SqlCommand Object, and is used for
executing statements that do not return result sets (ie.
statements like insert data , update data etc.).
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49. |
What providers does
Ado.net uses?
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The .NET Framework provides mainly
three data providers, they are
Microsoft SQL Server,
OLEDB,
ODBC.
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50. |
How will you close
the Database Conenction?
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Always close both the DataReader
and database connection after access to the database is no longer required.
dbread.Close()
dbconn.Close()
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51. |
What is a Clustered
Index?
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The data rows are
stored in order based on the clustered index key.
Data stored is in a
sequence of the index.
In a clustered index,
the physical order of the rows in the table is the same as the logical
(indexed) order of the key values.
A table can contain
only one clustered index.
A clustered index
usually provides faster access to data than does a non-clustered index
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52. |
What is a
Non–Clustered Index?
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The data rows are not
stored in any particular order, and there is no particular order to the
sequence of the data pages.
In a clustered index,
the physical order of the rows in the table is not same as the logical
(indexed) order of the key values.
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53. |
What type of data
model does an OleDbCommand object fill?
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An ADODataReader object.
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54. |
Which method do you
invoke on the DataAdapter control to load your generated dataset with data?
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DataAdapter’ fill () method is
used to fill load the data in dataset.
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55. |
What is difference
between Dataset. clone and Dataset.copy?
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Clone: - It only copies structure, does not copy data.
Copy: - Copies both structure and data. |
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56. |
What is DataAdapter?
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A data adapter represents a set of
methods used to perform a two-way data updating mechanism between a
disconnected DataTable and the database. It aggregates four commands: select,
update, insert and delete command. One adapter can only generate and fill one
table in a DataSet.
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57. |
What is a Command
Object?
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The ADO Command object is used to
execute a single query against a database. The query can perform actions like
creating, adding, retrieving, deleting or updating records.
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58. |
What is basic use of
DataView?
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“DataView” represents a complete
table or can be small section of rows depending on some criteria. It is best
used for sorting and finding data with in “datatable”.
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59. |
What is the use of
Connection Object?
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The ADO Connection Object is used
to create an open connection to a data source. Through this connection, you
can access and manipulate a database.
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60. |
What is a stored
procedure?
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A stored procedure is a
precompiled executable object that contains one or more SQL statements.
A stored procedure may be written to accept inputs and return output |
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61.
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What is Data
Provider?
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A set of libraries that is used to
communicate with data source. Eg: SQL data provider for SQL, Oracle data
provider for Oracle, OLE DB data provider for access, excel or mysql.
The data providers refers to a collection of objects that is responsible for providing and maintaining the connection to a database. |
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62. |
What is the provider
and namespaces being used to access oracle database?
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system.data.oledb
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63. |
Which object is used
to add a relationship between Data table objects?
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The DataRelation object is used to
add a relationship between Data table objects.
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64. |
What are the
benefits of LINQ?
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LINQ is available in
all .NET platform language such as C#.NET, VB.NET and F#.NET.
Easily transforms
data into objects and vice versa.
Reduce SQL injection
attacks, hence is more secure.
It makes it easier to
extra data from several data sources(XML, SQL, Objects etc).
Reduces the code size
as it provides relatively short codes for queries.
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65. |
What is the use of
System.Data namespace in ADO.Net?
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System.Data:
This contains the basic objects used for accessing and storing relational data such as dataset,datatable and data relation. |
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66. |
What are managed
providers?
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A managed provider is analogous to
ODBC driver or OLEDB provider. It performs operation of communicating with
the database. ADO.NET currently provides two distinct managed providers. The
SQL Server managed provider is used with SQL server and is a very efficient
way of communicating with SQL Server. OLEDB managed provider is used to
communicate with any OLEDB compliant database like Access or Oracle.
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67. |
How do I delete a
row from a DataTable?
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ds.Tables("data_table_name").Rows(i).Delete
dscmd.update(ds,"data_table_name") |
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68. |
What inside in
DataSet?
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Inside DataSet much like in
Database, there are tables, columns, constraints, relationships, views and so
forth.
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69. |
What is connection
pooling?
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Connection pooling refers to the
task of grouping database connection in cache to make them reusable because
opening new connections every time to a database is a time consuming process.
Therefore, connection pooling enables you to reuse already existing and
active database connections, whenever required, and increasing the
performance of your application.
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70. |
What is the use of
Ado.net connection?
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Establishes a connection to a
specific data source.
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71. |
What is
SqlConnection Object?
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The connection object
establishes connection with a database.
It includes the
information that is required to connect with a database like the database
server name, the database name, user name, password and other parameters.
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72. |
What two classes are
used to read data only?
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SqlDataReader
OldDbDataReader
classes to read data in a forward
directions only.
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73. |
What is SqlCommand
Object?
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The command object is
used for specifying the actions or commands to be executed on a database.
It uses the
connection object for identifying the database on which to execute commands.
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74. |
What is the use of
System. XML namespace in ADO.Net?
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System. XML :
This contains the basic objects required to create read, store, write and manipulate XML documents according to W3C recommendations. |
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75. |
What is dataset
Object?
|
The dataset object is
used for manipulating a memory image of a database.
The database object
that is loaded in memory and which is not connected with the physical
database is managed or manipulated through the dataset objects.
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76. |
What is
SqlDataAdapter Object?
|
The object takes the
help of all the above objects to work with the underlying database.
It makes use of the
connection object to establish connection with the database, uses the command
object to execute Sql commands on the connected database.
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77. |
What is the
DataTableCollection?
|
An ADO.NET DataSet contains a
collection of zero or more tables represented by DataTable objects.
The DataTableCollection contains all the DataTable objects in a DataSet. |
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78. |
How would you
connect to a database by using .NET?
|
The connection class is used to
connect a .NET application with a database.
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79. |
What are the
different methods available under sqlcommand class to access the data?
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ExecuteReader - Used where one or more records
are returned - SELECT Query.
ExecuteNonQuery - Used where it affects a state
of the table and no data is being queried - INSERT, UPDATE, DELETE, CREATE
and SET queries.
ExecuteScalar - Used where it returns a single record.
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