Core C# and .NET

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A1:

A .NET data provider must supply a connection, command, DataReader, and DataAdapter object to provide access to its data source.

A2:

b is the correct choice. a and c are invalid statements.

A3:

ExecuteNonQuery() executes a command but does not return a resultset.

ExecuteReader() returns a resultset in response to a query.

ExecuteScalar() returns a single value or null if the query generates no value.

A4:

The DataReader remains connected to a data source and returns data in a forward, read-only cursor. A DataAdapter is a bridge between a data source and an internal data store. It typically loads data from a data source into a DataSet. It can also update the data source.

A5:

A DataSet object contains one or more DataTables.

A6:

Rejected and Changed are not valid DataRowState values. Detached, Unchanged, and Modified are the other values.

A7:

A DataSet schema can be created (without loading actual XML data) by

DataInferXmlSchema(xml file);

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