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CommandBehavior Enum

Definition

Provides a description of the results of the query and its effect on the database.

This enumeration supports a bitwise combination of its member values.

public enum class CommandBehavior
[System.Flags]
public enum CommandBehavior
[<System.Flags>]
type CommandBehavior = 
Public Enum CommandBehavior
Inheritance
CommandBehavior
Attributes

Fields

Name Value Description
Default 0

The query may return multiple result sets. Execution of the query may affect the database state. Default sets no CommandBehavior flags, so calling ExecuteReader(CommandBehavior.Default) is functionally equivalent to calling ExecuteReader().

SingleResult 1

The query returns a single result set.

SchemaOnly 2

The query returns column information only. When using SchemaOnly, the .NET Framework Data Provider for SQL Server precedes the statement being executed with SET FMTONLY ON.

KeyInfo 4

The query returns column and primary key information. The provider appends extra columns to the result set for existing primary key and timestamp columns.

SingleRow 8

The query is expected to return a single row of the first result set. Execution of the query may affect the database state. Some .NET data providers may, but are not required to, use this information to optimize the performance of the command. When you specify SingleRow with the ExecuteReader() method of the OleDbCommand object, the .NET Framework Data Provider for OLE DB performs binding using the OLE DB IRow interface if it is available. Otherwise, it uses the IRowset interface. If your SQL statement is expected to return only a single row, specifying SingleRow can also improve application performance. It is possible to specify SingleRow when executing queries that are expected to return multiple result sets. In that case, where both a multi-result set SQL query and single row are specified, the result returned will contain only the first row of the first result set. The other result sets of the query will not be returned.

SequentialAccess 16

Provides a way for the DataReader to handle rows that contain columns with large binary values. Rather than loading the entire row, SequentialAccess enables the DataReader to load data as a stream. You can then use the GetBytes or GetChars method to specify a byte location to start the read operation, and a limited buffer size for the data being returned.

CloseConnection 32

When the command is executed, the associated Connection object is closed when the associated DataReader object is closed.

Remarks

For more information about this API, see Supplemental API remarks for CommandBehavior.

Applies to