memo_database

Database related structures and functions. More...

Data Structures
struct	memo_database
struct	memo_database_data
	Used to retrieve data from the database. More...
Typedefs
typedef struct memo_database	memo_database
Enumerations
enum	memo_database_data_types { INTEGER, STRING }
Functions
int	memo_database_close (memo_database *db)
	Closes the database.
void	memo_database_data_free (memo_database_data *data)
	Frees a memo_database_data structure.
memo_database_data *	memo_database_data_init ()
	Prepares a new memo_database_data structure.
int	memo_database_execute (memo_database *db, const char *query, memo_database_data *ret)
	Executes a given SQL query.
memo_word *	memo_database_find_word (memo_database *db, int key)
	Fetches a word with a given key from the database.
memo_word *	memo_database_find_word_by_value (memo_database *db, const char *value)
	Fetches a word with a given value from the database.
unsigned long	memo_database_get_last_change (memo_database *db)
	Returns the ID of the last change to the database.
int	memo_database_init (memo_database *db)
	Initialise the database.
memo_word **	memo_database_load_words_from_database_data (memo_database *db, memo_database_data *data)
	Creates a memo_word structure filled with the provided data.
memo_database *	memo_database_open (const char *filename)
	Prepares a memo_database.
void	memo_database_update_last_change (void *data, int action, char const *dbname, char const *rowname, sqlite3_int64 rowid)
	A callback updating memo_database::last_change.
memo_word **	memo_database_words_to_test (memo_database *db, int count)
	Chooses a set of words to be sent to the user.

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Detailed Description

Database related structures and functions.

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Typedef Documentation

typedef struct memo_database memo_database

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Enumeration Type Documentation

enum memo_database_data_types

Enumerator:

INTEGER
STRING

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Function Documentation

int memo_database_close

(

memo_database *

db

)

Closes the database.

Returns:

0.

void memo_database_data_free

(

memo_database_data *

data

)

Frees a memo_database_data structure.

memo_database_data* memo_database_data_init

(

)

Prepares a new memo_database_data structure.

int memo_database_execute	(	memo_database *	db,
		const char *	query,
		memo_database_data *	ret
	)

Executes a given SQL query.

Parameters:

	db	the database to which the query will be sent.
	query	the query.
	ret	pointer to a structure where the results will be stored. If it's NULL the results will not be saved.

Returns:

0 in case of success, negative values in case of errors.

memo_word* memo_database_find_word	(	memo_database *	db,
		int	key
	)

Fetches a word with a given key from the database.

Parameters:

	db	the database to search.
	key	the key we're looking for.

Returns:

pointer to the found word or NULL if it wasn't found or errors have occured.

memo_word* memo_database_find_word_by_value	(	memo_database *	db,
		const char *	value
	)

Fetches a word with a given value from the database.

Parameters:

	db	the database to search.
	value	the string we're looking for.

Returns:

pointer to the found word or NULL if it wasn't found or errors have occured.

unsigned long memo_database_get_last_change

(

memo_database *

db

)

Returns the ID of the last change to the database.

Returns:

value of memo_database::last_change field.

int memo_database_init

(

memo_database *

db

)

Initialise the database.

Create the structure of tables, unless they already exist. Internal use only.

Returns:

0 in case of success, negative values in case of errors.

memo_word** memo_database_load_words_from_database_data	(	memo_database *	db,
		memo_database_data *	data
	)

Creates a memo_word structure filled with the provided data.

Parameters:

	db	a database the word is in.
	data	data fetched from db to be inserted into the structure.

Returns:

a new memo_word structure.

memo_database* memo_database_open

(

const char *

filename

)

Prepares a memo_database.

Parameters:

filename

A filename of a file with a database.

Returns:

0 in case of success, negative values in case of errors.

void memo_database_update_last_change	(	void *	data,
		int	action,
		char const *	dbname,
		char const *	rowname,
		sqlite3_int64	rowid
	)

A callback updating memo_database::last_change.

memo_word** memo_database_words_to_test	(	memo_database *	db,
		int	count
	)

Chooses a set of words to be sent to the user.

Currently it chooses words of highest negative to positive answers ratio. It is hoped that a better algorithm will be implemented in foreseeable future.

The result array has to be freed.

Parameters:

	db	a database to take the words from.
	count	number of words to fetch.

Returns:

an array of pointers to chosen words.