Commands.cpp File Reference

#include "Commands.hpp"
#include <cstring>
#include <iostream>
#include "IdealBTree.hpp"
#include "Entry.hpp"

Include dependency graph for Commands.cpp:

Classes
struct	IdIndex
	Helper struct to store primary indexes. More...
struct	TitleIndex
	Helper struct to store secondary indexes. More...
struct	HashfileHeader
	Header data for the hashfile. More...

Macros
#define	ROOT   "./"
	File path to the folder where database files will be created. More...
#define	ID_TREE_FILENAME   "bd-idtree.bin"
	Primary index data filename. More...
#define	ID_TREE_FILEPATH   ROOT ID_TREE_FILENAME
	Full filepath to the primary index file. More...
#define	TITLE_TREE_FILENAME   "bd-titletree.bin"
	Secondary index data filename. More...
#define	TITLE_TREE_FILEPATH   ROOT TITLE_TREE_FILENAME
	Full filepath to the secondary index file. More...
#define	HASHFILE_FILENAME   "bd-hashfile.bin"
	Hashing file filename. More...
#define	HASHFILE_FILEPATH   ROOT HASHFILE_FILENAME
	Full filepath to the hashing file. More...
#define	HASHFILE_BLOCK_SIZE   BLOCK_SIZE
	Block size in bytes to be used in the hashing file More...
#define	PATIENCE_STEP   10000
	Show how many entries have already been read and indexed every once in a while. More...

Typedefs
typedef IdealBTree< IdIndex >	IdBTree
	Primary index B-tree. More...
typedef IdealBTree< TitleIndex >	TitleBTree
	Secondary index B-tree. More...
typedef Block< HashfileHeader, HASHFILE_BLOCK_SIZE >	HashfileHeaderBlock
	HashfileHeader block. More...
typedef Block< Entry, HASHFILE_BLOCK_SIZE >	EntryBlock
	Entry block. More...

Functions
bool	operator< (const IdIndex &index, int i)
	Less-than comparator between IdIndex::id and int. More...
bool	operator< (int i, const IdIndex &index)
	Less-than comparator between int and IdIndex::id. More...
bool	operator< (const TitleIndex &index, const char *title)
	Less-than comparator between TitleIndex::title and string. More...
bool	operator< (const char *title, const TitleIndex &index)
	Less-than comparator between string and TitleIndex::title. More...
void	upload (const char *filePath)
	Receives a CSV file and creates a database based on its contents. More...
void	findrec (long id)
	Finds an entry in the hashfile based on the entry's id. More...
void	seek1 (long id)
	Seeks an entry by its id using the primary index. More...
void	seek2 (const char *title)
	Seeks an entry by its title using the secondary index. More...

Macro Definition Documentation

#define HASHFILE_BLOCK_SIZE   BLOCK_SIZE

Block size in bytes to be used in the hashing file

#define HASHFILE_FILENAME   "bd-hashfile.bin"

Hashing file filename.

#define HASHFILE_FILEPATH   ROOT HASHFILE_FILENAME

Full filepath to the hashing file.

#define ID_TREE_FILENAME   "bd-idtree.bin"

Primary index data filename.

#define ID_TREE_FILEPATH   ROOT ID_TREE_FILENAME

Full filepath to the primary index file.

#define PATIENCE_STEP   10000

Show how many entries have already been read and indexed every once in a while.

#define ROOT   "./"

File path to the folder where database files will be created.

#define TITLE_TREE_FILENAME   "bd-titletree.bin"

Secondary index data filename.

#define TITLE_TREE_FILEPATH   ROOT TITLE_TREE_FILENAME

Full filepath to the secondary index file.

Typedef Documentation

typedef Block<Entry, HASHFILE_BLOCK_SIZE> EntryBlock

Entry block.

typedef Block<HashfileHeader, HASHFILE_BLOCK_SIZE> HashfileHeaderBlock

HashfileHeader block.

typedef IdealBTree<IdIndex> IdBTree

Primary index B-tree.

typedef IdealBTree<TitleIndex> TitleBTree

Secondary index B-tree.

Function Documentation

void findrec

(

long

id

)

Finds an entry in the hashfile based on the entry's id.

The hashfile uses perfect hashing. Therefore, the entry's offset in the file can be calculated readily from the id.

In case the id doesn't result in a valid offset, the procedure will inform.

Parameters

id	Id of the entry to find

bool operator<	(	const IdIndex &	index,
		int	i
	)

Less-than comparator between IdIndex::id and int.

bool operator<	(	int	i,
		const IdIndex &	index
	)

Less-than comparator between int and IdIndex::id.

bool operator<	(	const TitleIndex &	index,
		const char *	title
	)

Less-than comparator between TitleIndex::title and string.

bool operator<	(	const char *	title,
		const TitleIndex &	index
	)

Less-than comparator between string and TitleIndex::title.

void seek1

(

long

id

)

Seeks an entry by its id using the primary index.

Uses a B-tree to seek the entry by id within the primary index. In case no entry with the id is found, the procedure will inform.

Parameters

id	Id of the entry to find

void seek2

(

const char *

title

)

Seeks an entry by its title using the secondary index.

Uses a B-tree to seek the entry by title within the secondary index.

Will return the first entry found with the title.

In case no entry with the provided title is found, the procedure will inform.

Parameters

title

Title of the entry to find

void upload

(

const char *

filePath

)

Receives a CSV file and creates a database based on its contents.

Will load the data in the provided CSV file and, one by one, upload them into a database while indexing each entry by id and title using B-trees.

Each entry should be represented as a line in the CSV file with the following fields, one in each column:

Field	Type	Description
ID	Integer	Identifier of the article
Title	Alpha 300	Title of the article
Year	Integer	Publication year
Authors	Alpha 1024	List of the authors
Citations	Integer	Times the article has been cited
Update	Date time	Time of the last time the article was updated (YYYY-MM-DD HH:mm:SS)
Snippet	Alpha 1024	Text summary of the article's contents

Details of the execution will be printed as the program executes.

Creates tree files upon completion:

• db-hashfile.bin: where the entries will be stored;
• db-idindex.bin: primary index by id;
• db-titleindex.bin: secondary index by title.

The files will be overwritten if they already exist.

Parameters

filePath

Path to the CSV file with entries