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CCommand Class

 

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The latest version of this topic can be found at CCommand Class.

Provides methods to set and execute a command.

Syntax

template <  
   class TAccessor = CNoAccessor,  
   template < typename T > class TRowset = CRowset,  
   class TMultiple = CNoMultipleResults   
>  
class CCommand :   
   public CAccessorRowset <  
      TAccessor,   
      TRowset   
   >,  
   public CCommandBase,  
   public TMultiple  

Parameters

TAccessor
The type of accessor class (such as CDynamicParameterAccessor, CDynamicStringAccessor, or CEnumeratorAccessor) that you want the command to use. The default is CNoAccessor, which specifies that the class not support parameters or output columns.

TRowset
The type of rowset class (such as CArrayRowset or CNoRowset) that you want the command to use. The default is CRowset.

TMultiple
To use an OLE DB command that can return multiple results, specify CMultipleResults. Otherwise, use CNoMultipleResults. For details, see IMultipleResults.

Members

Methods

Close Closes the current command.
GetNextResult Fetches the next result when using multiple result sets.
Open Executes and optionally binds the command.

Inherited Methods

Create Creates a new command for the specified session, then sets the command text.
CreateCommand Creates a new command.
GetParameterInfo Gets a list of the command's parameters, their names, and their types.
Prepare Validates and optimizes the current command.
ReleaseCommand Releases the parameter accessor if necessary, then releases the command.
SetParameterInfo Specifies the native type of each command parameter.
Unprepare Discards the current command execution plan.

Remarks

Use this class when you need to perform a parameter-based operation or execute a command. If you merely need to open a simple rowset, use CTable instead.

The accessor class you are using determines the method of binding parameters and data.

Note that you cannot use stored procedures with the OLE DB Provider for Jet because that provider does not support stored procedures (only constants are allowed in query strings).

Requirements

Header: atldbcli.h

See Also

OLE DB Consumer Templates
OLE DB Consumer Templates Reference