VgEngine::VgQuery Class Reference

Holds a query that could be executed by the engine. More...

Public Types
enum	Operator { eEquals = 0 }

Public Member Functions
	VgQuery ()
	Constructor. More...
virtual	~VgQuery ()
	Destructor. More...
VgQuery &	where (const std::string &pKey, VgQuery::Operator pOp, const std::string &pValue)
	Adds a condition to the query. More...
VgQuery &	reset ()
	Resets the VgQuery conditions, useful when reusing VgQuery's. More...

Protected Attributes
Private *	mPrivate
	Private. More...

Friends
class	VgObjectBridge

Detailed Description

Holds a query that could be executed by the engine.

Warning

Performance note: this query mechanism should not be used intensively.

Version

2.0.9334

See Also

VgEngine::VgIEngine::execute

Member Enumeration Documentation

enum VgEngine::VgQuery::Operator

Enumerator
eEquals	Equality operator.

Constructor & Destructor Documentation

VgEngine::VgQuery::VgQuery

(

)

Constructor.

virtual VgEngine::VgQuery::~VgQuery ( )

virtual

Destructor.

Member Function Documentation

VgQuery& VgEngine::VgQuery::reset

(

)

Resets the VgQuery conditions, useful when reusing VgQuery's.

Returns

A reference of itself, allowing calls to be chained.

VgQuery& VgEngine::VgQuery::where	(	const std::string &	pKey,
		VgQuery::Operator	pOp,
		const std::string &	pValue
	)

Adds a condition to the query.

If the pKey has already been used replaces the condition for that key. ie lQuery.where("ID",...,"A").where("ID",...,"B") is equivalent to lQuery.where("ID",...,"B")

Parameters

pKey	Currently, the key can be 'class' or 'ID'.
pOp	The operation to be performed by the query. For the list of available operations, see VgEngine::VgQuery::Operator.
pValue	The value that will be the object of the query operation. When using the key 'class' this value must be the fully qualified name, for example 'Vg3DModule::VgPoint'. Currently, Vg3DModule::VgPoint, Vg3DModule::VgLine, Vg3DModule::VgIGeometry, and VgEngine::VgSpatial can be queried.

Example:

...
// Query for an specific ID
...
VgEngine::VgQuery lQuery;
lSpatials = lEngine->execute(lQuery.where("ID",VgEngine::VgQuery::eEquals,"L-250"));
...
// Query all VgPoint
VgEngine::VgQuery lQueryAll;
lSpatials = lEngine->execute(lQueryAll.where("class",VgEngine::VgQuery::eEquals,"Vg3DModule::VgPoint"));
...

Returns

A reference of itself, allowing calls to be chained.

Version

2.1.0 Allows for Vg3DModule::VgLine

2.1.3 documented all the classes that are accessible.

See Also

VgEngine::VgIEngine::execute for more complete example.

Friends And Related Function Documentation

friend class VgObjectBridge

friend

Member Data Documentation

Private* VgEngine::VgQuery::mPrivate

protected

Private.

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

• VgQuery.h