KDbFunctionExpression Class Reference

#include <KDbExpression.h>

Inheritance diagram for KDbFunctionExpression:

Public Member Functions
	KDbFunctionExpression ()
	KDbFunctionExpression (const KDbFunctionExpression &expr)
	KDbFunctionExpression (const QString &name)
	KDbFunctionExpression (const QString &name, const KDbNArgExpression &arguments)
KDbNArgExpression	arguments ()
QString	name () const
void	setArguments (const KDbNArgExpression &arguments)
void	setName (const QString &name)
KDbEscapedString	toString (const KDbDriver *driver, KDbQuerySchemaParameterValueListIterator *params=nullptr, KDb::ExpressionCallStack *callStack=nullptr) const
Public Member Functions inherited from KDbExpression
	KDbExpression ()
KDbExpression	clone () const
QDebug	debug (QDebug dbg, KDb::ExpressionCallStack *callStack) const
KDb::ExpressionClass	expressionClass () const
void	getQueryParameters (QList< KDbQuerySchemaParameter > *params)
bool	isBinary () const
bool	isConst () const
bool	isDateTimeType () const
bool	isFPNumericType () const
bool	isFunction () const
bool	isIntegerType () const
bool	isNArg () const
bool	isNull () const
bool	isNumericType () const
bool	isQueryParameter () const
bool	isTextType () const
bool	isUnary () const
bool	isValid () const
bool	isVariable () const
bool	operator!= (const KDbExpression &e) const
bool	operator== (const KDbExpression &e) const
KDbExpression	parent () const
void	setExpressionClass (KDb::ExpressionClass aClass)
void	setToken (KDbToken token)
KDbBinaryExpression	toBinary () const
KDbConstExpression	toConst () const
KDbFunctionExpression	toFunction () const
KDbToken	token () const
KDbNArgExpression	toNArg () const
KDbQueryParameterExpression	toQueryParameter () const
KDbEscapedString	toString (const KDbDriver *driver, KDbQuerySchemaParameterValueListIterator *params=nullptr, KDb::ExpressionCallStack *callStack=nullptr) const
KDbUnaryExpression	toUnary () const
KDbVariableExpression	toVariable () const
KDbField::Type	type () const
bool	validate (KDbParseInfo *parseInfo)

Static Public Member Functions
static QStringList	builtInAggregates ()
static KDbEscapedString	greatestOrLeastFunctionUsingCaseToString (const QString &name, const KDbDriver *driver, const KDbNArgExpression &args, KDbQuerySchemaParameterValueListIterator *params, KDb::ExpressionCallStack *callStack)
static bool	isBuiltInAggregate (const QString &function)
static KDbEscapedString	toString (const QString &name, const KDbDriver *driver, const KDbNArgExpression &args, KDbQuerySchemaParameterValueListIterator *params, KDb::ExpressionCallStack *callStack)
Static Public Member Functions inherited from KDbExpression
static KDb::ExpressionClass	classForToken (KDbToken token)

Protected Member Functions
	KDbFunctionExpression (const ExplicitlySharedExpressionDataPointer &ptr)
	KDbFunctionExpression (KDbExpressionData *data)
Protected Member Functions inherited from KDbExpression
	KDbExpression (const ExplicitlySharedExpressionDataPointer &ptr)
	KDbExpression (KDbExpressionData *data)
	KDbExpression (KDbExpressionData *data, KDb::ExpressionClass aClass, KDbToken token)
void	appendChild (const ExplicitlySharedExpressionDataPointer &child)
void	appendChild (const KDbExpression &child)
bool	checkBeforeInsert (const ExplicitlySharedExpressionDataPointer &child)
QList< ExplicitlySharedExpressionDataPointer >	children () const
int	indexOfChild (const KDbExpression &child, int from=0) const
void	insertChild (int i, const KDbExpression &child)
void	insertEmptyChild (int i)
int	lastIndexOfChild (const KDbExpression &child, int from=-1) const
void	prependChild (const KDbExpression &child)
bool	removeChild (const KDbExpression &child)
void	removeChild (int i)
void	setLeftOrRight (const KDbExpression &right, int index)
KDbExpression	takeChild (int i)

Additional Inherited Members
Protected Attributes inherited from KDbExpression
ExplicitlySharedExpressionDataPointer	d

Detailed Description

The KDbFunctionExpression class represents expression that use functional notation F(x, ...)

The functions list include:

• aggregation functions like SUM, COUNT, MAX, ...
• builtin functions like CURRENT_TIME()
• user defined functions

Definition at line 502 of file KDbExpression.h.

Constructor & Destructor Documentation

KDbFunctionExpression() [1/4]

KDbFunctionExpression::KDbFunctionExpression

(

)

Constructs a null function expression.

See also

KDbExpression::isNull()

Definition at line 1307 of file KDbFunctionExpression.cpp.

KDbFunctionExpression() [2/4]

KDbFunctionExpression::KDbFunctionExpression ( const QString &  name )

explicit

Constructs function expression with name name, without arguments.

Definition at line 1313 of file KDbFunctionExpression.cpp.

KDbFunctionExpression() [3/4]

KDbFunctionExpression::KDbFunctionExpression	(	const QString &	name,
		const KDbNArgExpression &	arguments
	)

Constructs function expression with name name and arguments arguments.

Definition at line 1319 of file KDbFunctionExpression.cpp.

KDbFunctionExpression() [4/4]

KDbFunctionExpression::KDbFunctionExpression

(

const KDbFunctionExpression &

expr

)

Constructs a copy of other function expression expr. Resulting object is not a deep copy but rather a reference to the object expr.

Definition at line 1326 of file KDbFunctionExpression.cpp.

Member Function Documentation

arguments()

KDbNArgExpression KDbFunctionExpression::arguments

(

)

Returns

list of arguments of the function.

Definition at line 1380 of file KDbFunctionExpression.cpp.

greatestOrLeastFunctionUsingCaseToString()

KDbEscapedString KDbFunctionExpression::greatestOrLeastFunctionUsingCaseToString ( const QString &  name, const KDbDriver *  driver, const KDbNArgExpression &  args, KDbQuerySchemaParameterValueListIterator *  params, KDb::ExpressionCallStack *  callStack  )

static

Returns

a native (driver-specific) GREATEST() and LEAST() function calls generated to string using CASE WHEN... keywords. This is a workaround for cases when LEAST()/GREATEST() function ignores NULL values and only returns NULL if all the expressions evaluate to NULL. Instead of using F(v0,..,vN), this is used: (CASE WHEN (v0) IS NULL OR .. OR (vN) IS NULL THEN NULL ELSE F(v0,..,vN) END) where F == GREATEST or LEAST. Actually it is needed by MySQL < 5.0.13 and PostgreSQL.

Definition at line 1391 of file KDbFunctionExpression.cpp.

name()

QString KDbFunctionExpression::name

(

)

const

Returns

name of the function.

Definition at line 1370 of file KDbFunctionExpression.cpp.

setArguments()

void KDbFunctionExpression::setArguments

(

const KDbNArgExpression &

arguments

)

Sets the list of arguments to arguments.

Definition at line 1385 of file KDbFunctionExpression.cpp.

setName()

void KDbFunctionExpression::setName

(

const QString &

name

)

Sets name of the function to name.

Definition at line 1375 of file KDbFunctionExpression.cpp.

toString() [1/2]

KDbEscapedString KDbExpression::toString

Returns

string as a representation of this expression element by running recursive calls. param, if not 0, points to a list item containing value of a query parameter (used in QueryParameterExpr). The result may depend on the optional driver parameter. If driver is 0, representation for portable KDbSQL dialect is returned.

Definition at line 469 of file KDbExpression.cpp.

toString() [2/2]

KDbEscapedString KDbFunctionExpression::toString ( const QString &  name, const KDbDriver *  driver, const KDbNArgExpression &  args, KDbQuerySchemaParameterValueListIterator *  params, KDb::ExpressionCallStack *  callStack  )

static

Constructs function expression with name name and args args.

Definition at line 1359 of file KDbFunctionExpression.cpp.

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The documentation for this class was generated from the following files:

• KDbExpression.h
• KDbFunctionExpression.cpp