Data.DB.TParamType
Delphi
TParamType = (ptUnknown, ptInput, ptOutput, ptInputOutput, ptResult);
C++
enum DECLSPEC_DENUM TParamType : unsigned char { ptUnknown, ptInput, ptOutput, ptInputOutput, ptResult };
Properties
Type | Visibility | Source | Unit | Parent |
---|---|---|---|---|
enum | public | Data.DB.pas Data.DB.hpp |
Data.DB | Data.DB |
Description
TParamType and TParamTypes represent the use of parameters on datasets that represent queries or stored procedures.
TParamType indicates how a query or stored procedure parameter is used. TParamTypes is a set of parameter types that can be used to filter parameters so that an application need only work with those parameters that are of interest.
The DbClient unit defines a constant, AllParamTypes, of type TParamTypes that represents any possible parameter type:
const AllParamTypes = [ptUnknown, ptInput, ptOutput, ptInputOutput, ptResult];
- define AllParamTypes TParamTypes() << ptUnknown << ptInput << ptOutput << ptInputOutput << ptResult )
TParamType includes the following values:
Value | Description |
---|---|
ptUnknown |
Unknown or undetermined. Before executing a stored procedure, the application must set parameters of this type to another kind. |
ptInput |
Used to input a field value. Identifies a parameter used to pass values to a query or stored procedure for processing. |
ptOutput |
Used to output a field value. Identifies a parameter used by a stored procedure to return values to an application. |
ptInputOutput |
Used for both input and output. |
ptResult |
Used as a return value. Identifies a parameter used by a stored procedure to return an error or status value. A stored procedure can only have one parameter of type ptResult. |