Query execution environment holds the function registry and the execution context. More...

#include <util/qparse/query_exec.hpp>

Inheritance diagram for CQueryExec:

Collaboration diagram for CQueryExec:

Public Types
typedef unsigned int	TFieldID

Public Types inherited from CObject
enum	EAllocFillMode { eAllocFillNone = 1 , eAllocFillZero , eAllocFillPattern }
	Control filling of newly allocated memory. More...

typedef CObjectCounterLocker	TLockerType
	Default locker type for CRef. More...

typedef atomic< Uint8 >	TCounter
	Counter type is CAtomiCounter. More...

typedef Uint8	TCount
	Alias for value type of counter. More...

Public Member Functions
	CQueryExec ()

virtual	~CQueryExec ()

void	AddFunc (CQueryParseNode::EType func_type, CQueryFunctionBase *func)
	Register function implementation. More...

void	AddImplicitSearchFunc (CQueryFunctionBase *func)
	This is a callback for implicit search nodes Our syntax allows queries like (a=1) AND "search_term" Execution recognises "search_term" connected with logical operation represents a special case. More...

CQueryFunctionBase *	GetImplicitSearchFunc ()

CQueryFunctionBase *	GetFunc (CQueryParseNode::EType func_type)
	Return query function pointer (if registered). More...

virtual void	CallFunction (const string &name, CQueryParseTree::TNode &node)
	Extend this function to look up and invoke functions that appear in the query. More...

virtual void	Evaluate (CQueryParseTree &qtree)
	Run query tree evaluation. More...

virtual void	Evaluate (CQueryParseTree &qtree, CQueryParseTree::TNode &node)

virtual bool	ResolveIdentifier (const std::string &, bool &)
	If query has an identifier, this will resolve it in an application-specific way. More...

virtual bool	ResolveIdentifier (const std::string &, Int8 &)

virtual bool	ResolveIdentifier (const std::string &, double &)

virtual bool	ResolveIdentifier (const std::string &, std::string &)

virtual bool	ResolveIdentifier (const TFieldID &, bool &)

virtual bool	ResolveIdentifier (const TFieldID &, Int8 &)

virtual bool	ResolveIdentifier (const TFieldID &, double &)

virtual bool	ResolveIdentifier (const TFieldID &, std::string &)

virtual bool	HasIdentifier (const std::string &)

virtual TFieldID	GetIdentifier (const std::string &)

virtual CQueryParseNode::EType	IdentifierType (const std::string &)
	Some applications may know the type of an identifier. More...

virtual void	EvalStart ()

virtual bool	EvalNext (CQueryParseTree &)
	Move to (iterate) to next entry. More...

virtual bool	EvalComplete ()

int	GetQueriedCount () const

int	GetExceptionCount () const

Public Member Functions inherited from CObject
	CObject (void)
	Constructor. More...

	CObject (const CObject &src)
	Copy constructor. More...

virtual	~CObject (void)
	Destructor. More...

CObject &	operator= (const CObject &src) THROWS_NONE
	Assignment operator. More...

bool	CanBeDeleted (void) const THROWS_NONE
	Check if object can be deleted. More...

bool	IsAllocatedInPool (void) const THROWS_NONE
	Check if object is allocated in memory pool (not system heap) More...

bool	Referenced (void) const THROWS_NONE
	Check if object is referenced. More...

bool	ReferencedOnlyOnce (void) const THROWS_NONE
	Check if object is referenced only once. More...

void	AddReference (void) const
	Add reference to object. More...

void	RemoveReference (void) const
	Remove reference to object. More...

void	ReleaseReference (void) const
	Remove reference without deleting object. More...

virtual void	DoNotDeleteThisObject (void)
	Mark this object as not allocated in heap – do not delete this object. More...

virtual void	DoDeleteThisObject (void)
	Mark this object as allocated in heap – object can be deleted. More...

void *	operator new (size_t size)
	Define new operator for memory allocation. More...

void *	operator new[] (size_t size)
	Define new[] operator for 'array' memory allocation. More...

void	operator delete (void *ptr)
	Define delete operator for memory deallocation. More...

void	operator delete[] (void *ptr)
	Define delete[] operator for memory deallocation. More...

void *	operator new (size_t size, void *place)
	Define new operator. More...

void	operator delete (void ptr, void place)
	Define delete operator. More...

void *	operator new (size_t size, CObjectMemoryPool *place)
	Define new operator using memory pool. More...

void	operator delete (void ptr, CObjectMemoryPool place)
	Define delete operator. More...

virtual void	DebugDump (CDebugDumpContext ddc, unsigned int depth) const
	Define method for dumping debug information. More...

Public Member Functions inherited from CDebugDumpable
	CDebugDumpable (void)

virtual	~CDebugDumpable (void)

void	DebugDumpText (ostream &out, const string &bundle, unsigned int depth) const

void	DebugDumpFormat (CDebugDumpFormatter &ddf, const string &bundle, unsigned int depth) const

void	DumpToConsole (void) const

Protected Types
typedef vector< CQueryFunctionBase * >	TFuncReg

Protected Member Functions
CQueryParseTree *	GetQTree ()

Protected Member Functions inherited from CObject
virtual void	DeleteThis (void)
	Virtual method "deleting" this object. More...

Protected Attributes
TFuncReg	m_FuncReg

unique_ptr< CQueryFunctionBase >	m_ImplicitSearchFunc

CQueryParseTree *	m_QTree

int	m_ExceptionCount

int	m_QueriedCount

Private Member Functions
	CQueryExec (const CQueryExec &)

CQueryExec &	operator= (const CQueryExec &)

Friends
class	CQueryFunctionBase

Additional Inherited Members
Static Public Member Functions inherited from CObject
static NCBI_XNCBI_EXPORT void	ThrowNullPointerException (void)
	Define method to throw null pointer exception. More...

static NCBI_XNCBI_EXPORT void	ThrowNullPointerException (const type_info &type)

static EAllocFillMode	GetAllocFillMode (void)

static void	SetAllocFillMode (EAllocFillMode mode)

static void	SetAllocFillMode (const string &value)
	Set mode from configuration parameter value. More...

Static Public Member Functions inherited from CDebugDumpable
static void	EnableDebugDump (bool on)

Static Public Attributes inherited from CObject
static const TCount	eCounterBitsCanBeDeleted = 1 << 0
	Define possible object states. More...

static const TCount	eCounterBitsInPlainHeap = 1 << 1
	Heap signature was found. More...

static const TCount	eCounterBitsPlaceMask
	Mask for 'in heap' state flags. More...

static const int	eCounterStep = 1 << 2
	Skip over the "in heap" bits. More...

static const TCount	eCounterValid = TCount(1) << (sizeof(TCount) * 8 - 2)
	Minimal value for valid objects (reference counter is zero) Must be a single bit value. More...

static const TCount	eCounterStateMask
	Valid object, and object in heap. More...

Detailed Description

Query execution environment holds the function registry and the execution context.

Execution context is vaguely defined term, it can be anything query functions need: open files, databases, network connections, pools of threads, etc.


Query execution consists of distinct several phases:
1.Construction of execution environment
   All function implementations are registered in CQueryExec
2.Query parsing (see CQueryParseTree). This step transforms query (string)
  into query tree, the tree reflects operations precedence
3.Parsing tree validation and transformation (optional)
4.Query execution-evaluation. Execution engine traverses the query tree calling
  appropriate functions to do expression(query tree node) evaluation.
  Execution results for every tree node are stored in the tree as user
  objects (classes derived from IQueryParseUserObject).

Definition at line 143 of file query_exec.hpp.

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

include/util/qparse/query_exec.hpp
src/util/qparse/query_exec.cpp

Public Types

Public Member Functions

Protected Types

Protected Member Functions

Protected Attributes

Private Member Functions

Friends

Additional Inherited Members

Detailed Description