What does SqlDataReader return?
The Read method returns true as long as there are rows to read from the SqlDataReader object. If there are no more rows to read, then this method will simply return false. Here, in the below example, we are retrieving the data by using the string key names, nothing but the column names returned by the select clause.
Which of the following property of SqlDataReader class is used to check if SqlDataReader has rows?
|HasRows||It is used to get a value that indicates whether the SqlDataReader contains one or more rows.|
|IsClosed||It is used to retrieve a boolean value that indicates whether the specified SqlDataReader instance has been closed.|
Which method provides SqlDataReader object from SqlCommand object?
To create a SqlDataReader, you must call the ExecuteReader method of the SqlCommand object, instead of directly using a constructor.
What is the use of SqlDataReader class?
The SqlDataReader is used to read a row of record at a time which is got using SqlCommand. It is read only, which means we can only read the record; it can not be edited. And also it is forward only, which means you can not go back to a previous row (record).
What does ExecuteScalar return?
ExecuteScalar() Method:ExecuteScalar() method is used to retrieve a single value from database. It executes the defined query and returns the value in the first column of the first row in the selected result set and ignores all other columns and rows in the result set.
What is DataReader and DataAdapter?
DataAdapter is an intermediate layer/ middleware which acts a bridge between the DataSet and a Database whereas DataReader provides forward-only, read-only access to data using a server-side cursor (simply put it is ued to read the data).
What is use of SqlDataReader?
What is a SqlDataReader object?
SqlDataReader Object provides a connection oriented data access to the SQL Server data Sources from C# applications. ExecuteReader() in the SqlCommand Object sends the SQL statements to the SqlConnection Object and populate a SqlDataReader Object based on the SQL statement or Stored Procedures.
Is SqlDataReader faster than SqlDataAdapter?
SqlDatareader will be faster to use because it works in a connected state which means the first result is returned from query as soon as its available ..
What does SqlDataReader read do?
SqlDataReader objects allow you to read data in a fast forward-only manner. You obtain data by reading each row from the data stream. Call the Close method of the SqlDataReader to ensure there are not any resource leaks.
What is a sqldatarecord object?
The SqlDataRecord object represents a single row of data, along with its related metadata. Managed stored procedures may send to the client result sets that are not from a SqlDataReader.
How to create a sqldatareader in SQL Server?
To create a SqlDataReader, you must call the ExecuteReader method of the SqlCommand object, instead of directly using a constructor. While the SqlDataReader is being used, the associated SqlConnection is busy serving the SqlDataReader, and no other operations can be performed on the SqlConnection other than closing it.
Can the recordsaffected property be accessed while the sqldatareader exists?
Although the RecordsAffected property may be accessed while the SqlDataReader exists, always call Close before returning the value of RecordsAffected to guarantee an accurate return value.
What happens when you create a new sqldatarecord?
Creating many new SqlDataRecord objects could severely deplete memory and adversely affect performance. Inititializes a new SqlDataRecord instance with the schema based on the array of SqlMetaData objects passed as an argument. Gets the number of columns in the data row.