Data.DB.TParamType

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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];

  1. 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.