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.
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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. |
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
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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. |
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 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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8.
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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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9.
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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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10.
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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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11.
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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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12.
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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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13.
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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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14.
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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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15.
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What is the data
provider name to connect to Access database?
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Microsoft.Access
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16.
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Which namespaces are
used for data access?
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System.Data
System.Data.OleDB
System.Data.SQLClient
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17.
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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. |
18.
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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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19.
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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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20.
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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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21.
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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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22.
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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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23.
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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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24.
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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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25.
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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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26.
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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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27.
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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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28.
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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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29.
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Name some ADO.NET
Objects?
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Connection Object
DataReader Object
Command Object
DataSet Object
DataAdapter Object
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30.
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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.
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31.
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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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32.
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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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33.
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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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34.
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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); |
35.
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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"; |
36.
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What is the provider
and namespaces being used to access oracle database?
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system.data.oledb
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37.
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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. |
38.
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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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39.
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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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40.
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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") |
41.
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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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42.
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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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43.
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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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44.
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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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45.
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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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46.
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What are acid
properties?
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Atomicity
Consistency
Isolation
Durability
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47.
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What is
DataRowCollection?
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Similar to
DataTableCollection, to represent each row in each Table we have
DataRowCollection.
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48.
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What is the use of
Ado.net connection?
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Establishes a
connection to a specific data source.
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49.
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What are basic
methods of Dataadapter?
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Fill
FillSchema
Update
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50.
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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. |
51.
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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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52.
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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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53.
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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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54.
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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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