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DataAsyncCommand.OnDeriveSchema Method

Definition

Dispatches the asynchronous derive schema operation to the synchronous DeriveSchema(String, DataCommandType, IVsDataParameter[], Int32) method call.

protected:
 virtual Microsoft::VisualStudio::Data::Services::SupportEntities::IVsDataReader ^ OnDeriveSchema(System::String ^ command, Microsoft::VisualStudio::Data::Services::SupportEntities::DataCommandType commandType, cli::array <Microsoft::VisualStudio::Data::Services::SupportEntities::IVsDataParameter ^> ^ parameters, int commandTimeout);
protected virtual Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader OnDeriveSchema (string command, Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType commandType, Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataParameter[] parameters, int commandTimeout);
abstract member OnDeriveSchema : string * Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType * Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataParameter[] * int -> Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader
override this.OnDeriveSchema : string * Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType * Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataParameter[] * int -> Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader
Protected Overridable Function OnDeriveSchema (command As String, commandType As DataCommandType, parameters As IVsDataParameter(), commandTimeout As Integer) As IVsDataReader

Parameters

command
String

The command for which the schema is derived.

commandType
DataCommandType

A value from the DataCommandType enumeration representing the command type for the indicated command. The value specifies how to interpret the contents of the command parameter.

parameters
IVsDataParameter[]

A list of parameters to pass with the command.

commandTimeout
Int32

Amount of time, in seconds, before which the command times out.

Returns

An IVsDataReader object. This object provides a forward-only, read-only data stream that describes the layout of items and blocks, that is, the schema, for the reader object returned upon executing the specified command.

Applies to