ibis::selected Class Reference

A data structure to store the select clause of a query. More...

#include <util.h>

List of all members.

Public Types
typedef std::vector < std::string > ::const_iterator	const_iterator
	An iterator through the column names of the select clause.
enum	FUNCTION {   NIL, AVG, MAX, MIN,   SUM, VARPOP, VARSAMP, STDPOP,   STDSAMP, DISTINCT }
Public Member Functions
const_iterator	begin () const
void	clear ()
bool	empty () const
const_iterator	end () const
uint32_t	find (const char *key) const
	Return the first occurrence of the string.
FUNCTION	getFunction (uint32_t i) const
const char *	getName (uint32_t i) const
	Access the ith column name of the select clause.
const std::vector< std::string > &	getNames () const
	Return the list of names stored internally.
std::string	getTerm (uint32_t i) const
	Return the ith term, with the function name.
uint32_t	nPlain () const
const char *	operator* () const
	Output a stringlized version of the select clause.
const char *	operator[] (uint32_t i) const
void	remove (const std::vector< uint32_t > &ents)
	Remove the entries specified.
void	select (const std::vector< const char * > &nl, bool sort=true)
void	select (const char *str, bool sort=true)
	Parse the select clause. By default, place the functions last.
	selected (const char *str)
	The default constructor leaves data members empty.
uint32_t	size () const
std::string	uniqueNames () const
	Return all unique column names.

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Detailed Description

A data structure to store the select clause of a query.

A select clause may contain a list of names plus a list of simple functions. The supported functions are avg, max, min and sum. Each of these functions can only take a single name as it argument.

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Member Function Documentation

uint32_t ibis::selected::find

(

const char *

key

)

const

Return the first occurrence of the string.

Use a simple linear search to locate the desired column name.

Returns the value of size if the given key in not in the list of selected components.

Referenced by ibis::query::result::getDouble(), ibis::query::result::getFloat(), ibis::query::result::getInt(), ibis::query::result::getLong(), ibis::query::result::getUInt(), ibis::query::result::getULong(), ibis::bundles::reorder(), and ibis::bundles::truncate().

const char* ibis::selected::getName

(

uint32_t

i

)

const [inline]

Access the ith column name of the select clause.

In case of a function, it returns the name of the argument rather than the whole function. This operator is only intended to be used to extract the column values.

void ibis::selected::select	(	const char *	str,
		bool	sort = true
	)

Parse the select clause. By default, place the functions last.

Parse the incoming string into a list of names plus functions.

References ibis::util::delimiters, ibis::gVerbose, and ibis::util::logMessage().

Referenced by ibis::bundles::reorder(), selected(), ibis::query::setSelectClause(), and ibis::bundles::truncate().

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

• util.h
• query.cpp