SourcePro® API Reference Guide

 
Loading...
Searching...
No Matches
RWDBExprFuncDef0 Class Reference

Specialization of the base class RWDBExprFormDefinition used to define SQL functions that take no parameters. More...

#include <rw/db/func.h>

Inheritance diagram for RWDBExprFuncDef0:
RWDBExprFormDefinition

Public Member Functions

 RWDBExprFuncDef0 (const RWCString &functionName)
 
virtual RWDBExpr operator() ()
 

Private Member Functions

virtual RWDBExpr operator() (const RWDBExpr &)
 
virtual RWDBExpr operator() (const RWDBExpr &, const RWDBExpr &)
 
virtual RWDBExpr operator() (const RWDBExpr &, const RWDBExpr &, const RWDBExpr &)
 
virtual RWDBExpr operator() (const RWDBExpr &, const RWDBExpr &, const RWDBExpr &, const RWDBExpr &)
 
- Private Member Functions inherited from RWDBExprFormDefinition
 RWDBExprFormDefinition ()
 
 RWDBExprFormDefinition (const RWCString &formatString)
 

Detailed Description

RWDBExprFuncDef0 is a specialization of the base class RWDBExprFormDefinition. This class provides a simplified mechanism for defining SQL functions taking no parameters. Unlike the base class, this class does not require positional placeholders in its function definitions. Also, since the number of required parameters is fixed, compile-time checking can be done on the number of parameters actually passed.

Synopsis
#include <rw/db/func.h>
RWDBExprFuncDef0 myFunc("myFunc");
Specialization of the base class RWDBExprFormDefinition used to define SQL functions that take no par...
Definition func.h:182
See also

RWDBCritFuncDef0 provides a parallel mechanism for defining an RWDBCriterion, rather than an RWDBExpr.

The RWDBExprFormDefinition base class may be used directly to gain additional flexibility.

See RWDBExpr for details on SQL expressions in the DB Interface Module, as well as for a complete listing of predefined SQL functions.

Example
Please refer to the example in RWDBExprFuncDef3.

Constructor & Destructor Documentation

◆ RWDBExprFuncDef0()

RWDBExprFuncDef0::RWDBExprFuncDef0 ( const RWCString & functionName)

Creates an RWDBExprFuncDef0 for a functional expression that takes no parameters. After such an RWDBExprFuncDef0 is instantiated, functionName may be used as though it were a predefined function.

Member Function Documentation

◆ operator()() [1/5]

virtual RWDBExpr RWDBExprFuncDef0::operator() ( )
virtual

Returns an RWDBExpr in the form of a function with zero parameters whose name is the name which was passed to self's constructor.

Reimplemented from RWDBExprFormDefinition.

◆ operator()() [2/5]

virtual RWDBExpr RWDBExprFuncDef0::operator() ( const RWDBExpr & )
privatevirtual

Not applicable to this class. This class defines SQL functions taking no parameters.

Reimplemented from RWDBExprFormDefinition.

◆ operator()() [3/5]

virtual RWDBExpr RWDBExprFuncDef0::operator() ( const RWDBExpr & ,
const RWDBExpr &  )
privatevirtual

Not applicable to this class. This class defines SQL functions taking no parameters.

Reimplemented from RWDBExprFormDefinition.

◆ operator()() [4/5]

virtual RWDBExpr RWDBExprFuncDef0::operator() ( const RWDBExpr & ,
const RWDBExpr & ,
const RWDBExpr &  )
privatevirtual

Not applicable to this class. This class defines SQL functions taking no parameters.

Reimplemented from RWDBExprFormDefinition.

◆ operator()() [5/5]

virtual RWDBExpr RWDBExprFuncDef0::operator() ( const RWDBExpr & ,
const RWDBExpr & ,
const RWDBExpr & ,
const RWDBExpr &  )
privatevirtual

Not applicable to this class. This class defines SQL functions taking no parameters.

Reimplemented from RWDBExprFormDefinition.

Copyright © 2024 Rogue Wave Software, Inc., a Perforce company. All Rights Reserved.