IVsDataCommand.DeriveSchema Method
Definition
Important
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Overloads
| DeriveSchema(String) |
When implemented by a class, derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader. |
| DeriveSchema(String, DataCommandType) |
When implemented by a class, 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[]) |
When implemented by a class, 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) |
When implemented by a class, derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader. |
DeriveSchema(String)
When implemented by a class, derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader.
public:
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.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.
Applies to
DeriveSchema(String, DataCommandType)
When implemented by a class, derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader.
public:
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.IVsDataReaderPublic Function DeriveSchema (command As String, commandType As DataCommandType) As IVsDataReaderParameters
- command
- String
A command for which to derive the schema that is specific to a data source.
- commandType
- DataCommandType
A value from the DataCommandType enumeration representing the command type for the indicated command, specifying how to interpret the contents of the command parameter.
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
DeriveSchema(String, DataCommandType, IVsDataParameter[])
When implemented by a class, derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader.
public:
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.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 that is to a data source.
- commandType
- DataCommandType
A value from the DataCommandType enumeration representing the command type for the indicated command, specifying how to interpret the contents of the command parameter.
- parameters
- IVsDataParameter[]
An array of DataParameter objects for the specified command type. While this is an input parameter, the DDEX provider is still able to set properties on individual out and return value parameters. However, these will not be populated when deriving schemas.
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
DeriveSchema(String, DataCommandType, IVsDataParameter[], Int32)
When implemented by a class, derives the schema returned from a specified command. The schema indicates the layout of items and blocks in a data reader.
public:
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 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.IVsDataReaderPublic 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 that is specific to a data source.
- commandType
- DataCommandType
A value from the DataCommandType enumeration representing the command type for the indicated command, specifying how to interpret the contents of the command parameter.
- parameters
- IVsDataParameter[]
An array of DataParameter objects for the specified command type. While this is an input parameter, the DDEX provider is still able to set properties on individual out and return value parameters. However, these will not be populated when deriving schemas.
- 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.