DataCommand.DeriveSchema Method
Definition
Important
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Overloads
| DeriveSchema(String) |
Derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader. |
| DeriveSchema(String, DataCommandType) |
Derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader. |
| DeriveSchema(String, DataCommandType, IVsDataParameter[]) |
Derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader. |
| DeriveSchema(String, DataCommandType, IVsDataParameter[], Int32) |
Derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader. |
DeriveSchema(String)
Derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader.
public:
virtual Microsoft::VisualStudio::Data::Services::SupportEntities::IVsDataReader ^ DeriveSchema(System::String ^ command);public Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader DeriveSchema (string command);abstract member DeriveSchema : string -> Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader
override this.DeriveSchema : string -> Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReaderPublic Function DeriveSchema (command As String) As IVsDataReaderParameters
- command
- String
A command for which to derive the schema that is specific to a data source.
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.
Implements
Exceptions
The command parameter is null.
Applies to
DeriveSchema(String, DataCommandType)
Derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader.
public:
virtual Microsoft::VisualStudio::Data::Services::SupportEntities::IVsDataReader ^ DeriveSchema(System::String ^ command, Microsoft::VisualStudio::Data::Services::SupportEntities::DataCommandType commandType);public Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader DeriveSchema (string command, Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType commandType);abstract member DeriveSchema : string * Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType -> Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader
override this.DeriveSchema : string * Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType -> Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReaderPublic Function DeriveSchema (command As String, commandType As DataCommandType) As IVsDataReaderParameters
- command
- String
A command for which to derive the schema specific to a data source.
- commandType
- DataCommandType
The type of the command that specifies how to interpret the contents of the command parameter. The command type could either be a value from the DataCommandType enumeration or a custom command type defined by a provider, which can be passed in by forcing a cast from an integer to the DataCommandType enumeration.
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.
Implements
Exceptions
The command parameter is null.
Applies to
DeriveSchema(String, DataCommandType, IVsDataParameter[])
Derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader.
public:
virtual Microsoft::VisualStudio::Data::Services::SupportEntities::IVsDataReader ^ DeriveSchema(System::String ^ command, Microsoft::VisualStudio::Data::Services::SupportEntities::DataCommandType commandType, cli::array <Microsoft::VisualStudio::Data::Services::SupportEntities::IVsDataParameter ^> ^ parameters);public Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader DeriveSchema (string command, Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType commandType, Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataParameter[] parameters);abstract member DeriveSchema : string * Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType * Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataParameter[] -> Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader
override this.DeriveSchema : string * Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType * Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataParameter[] -> Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReaderPublic Function DeriveSchema (command As String, commandType As DataCommandType, parameters As IVsDataParameter()) As IVsDataReaderParameters
- command
- String
A command for which to derive the schema specific to a data source.
- commandType
- DataCommandType
The type of the command that specifies how to interpret the contents of the command parameter. The command type could either be a value from the DataCommandType enumeration or a custom command type defined by a provider, which can be passed in by forcing a cast from an integer to the DataCommandType enumeration.
- parameters
- IVsDataParameter[]
An array of IVsDataParameter objects representing the command parameters for the specified command type.
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.
Implements
Exceptions
The command parameter is null.
Applies to
DeriveSchema(String, DataCommandType, IVsDataParameter[], Int32)
Derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader.
public:
virtual Microsoft::VisualStudio::Data::Services::SupportEntities::IVsDataReader ^ DeriveSchema(System::String ^ command, Microsoft::VisualStudio::Data::Services::SupportEntities::DataCommandType commandType, cli::array <Microsoft::VisualStudio::Data::Services::SupportEntities::IVsDataParameter ^> ^ parameters, int commandTimeout);public virtual Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader DeriveSchema (string command, Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType commandType, Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataParameter[] parameters, int commandTimeout);abstract member DeriveSchema : string * Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType * Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataParameter[] * int -> Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReader
override this.DeriveSchema : string * Microsoft.VisualStudio.Data.Services.SupportEntities.DataCommandType * Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataParameter[] * int -> Microsoft.VisualStudio.Data.Services.SupportEntities.IVsDataReaderPublic Overridable Function DeriveSchema (command As String, commandType As DataCommandType, parameters As IVsDataParameter(), commandTimeout As Integer) As IVsDataReaderParameters
- command
- String
A command for which to derive the schema specific to a data source.
- commandType
- DataCommandType
The type of the command that specifies how to interpret the contents of the command parameter. The command type could either be a value from the DataCommandType enumeration or a custom command type defined by a provider, which can be passed in by forcing a cast from an integer to the DataCommandType enumeration.
- parameters
- IVsDataParameter[]
An array of IVsDataParameter objects representing the command parameters for the specified command type.
- commandTimeout
- Int32
The length of time, in seconds, to block the client before canceling the schema derivation and returning to the caller. A value of 0 indicates infinite time-out; a value of -1 indicates a provider default.
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.
Implements
Exceptions
The command parameter is null.
The commandTimeout parameter is less than -1.