C# ADO.NET OleDbCommand - ExecuteScalar
The ExecuteScalar() method within the C# OleDbCommand Object serves the purpose of retrieving a single value from the Database upon the execution of SQL Statements or Stored Procedures.
ExecuteScalar() method
When invoked, the ExecuteScalar() method executes the provided SQL statement or Stored Procedure and returns a scalar value. This scalar value is extracted from the first column of the first row within the returned Result Set. If the Result Set contains multiple columns or rows, the ExecuteScalar() method disregards all other values and solely returns the value from the first column of the first row. In the event that the Result Set is empty, the ExecuteScalar() method returns a NULL reference.
This method proves particularly useful when working with aggregate functions such as Count(*) or Sum(), where a single value is expected as the result. By leveraging the ExecuteScalar() method, developers can conveniently retrieve the desired aggregated value.
Moreover, compared to the ExecuteReader() method, the ExecuteScalar() method utilizes fewer system resources. This makes it an efficient choice in scenarios where only a single value is required, minimizing resource consumption and enhancing overall performance.
Full Source C#Conclusion
The ExecuteScalar() method in the C# OleDbCommand Object allows developers to retrieve a single value from the Database by executing SQL Statements or Stored Procedures. It returns the value from the first column of the first row in the Result Set, making it particularly beneficial for working with aggregate functions. Additionally, the method's efficiency in resource usage sets it apart from the ExecuteReader() method in certain use cases.
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