Files
file	qofquery.h
	find objects that match a certain expression.

file	qofquerycore.h
	API for providing core Query data types.

Data Structures
struct	_QofQueryPredData

Macros
#define	QOF_MOD_QUERY "qof.query"

#define	QOF_QUERY_FIRST_TERM QOF_QUERY_AND

#define	QUERY_DEFAULT_SORT "QofQueryDefaultSort"

#define	QOF_PARAM_BOOK "book"

#define	QOF_PARAM_GUID "guid"

#define	QOF_PARAM_KVP "kvp"

#define	QOF_PARAM_ACTIVE "active"

#define	QOF_PARAM_VERSION "version"

Typedefs
typedef struct _QofQuery	QofQuery

typedef struct _QofQueryPredData	QofQueryPredData

typedef GSList	QofQueryParamList

Enumerations
enum	QofQueryOp { QOF_QUERY_AND = 1, QOF_QUERY_OR, QOF_QUERY_NAND, QOF_QUERY_NOR, QOF_QUERY_XOR }

enum	QofQueryCompare { QOF_COMPARE_LT = 1, QOF_COMPARE_LTE, QOF_COMPARE_EQUAL, QOF_COMPARE_GT, QOF_COMPARE_GTE, QOF_COMPARE_NEQ, QOF_COMPARE_CONTAINS, QOF_COMPARE_NCONTAINS }

enum	QofStringMatch { QOF_STRING_MATCH_NORMAL = 1, QOF_STRING_MATCH_CASEINSENSITIVE }

enum	QofDateMatch { QOF_DATE_MATCH_NORMAL = 1, QOF_DATE_MATCH_DAY }

enum	QofNumericMatch { QOF_NUMERIC_MATCH_DEBIT = 1, QOF_NUMERIC_MATCH_CREDIT, QOF_NUMERIC_MATCH_ANY }

enum	QofGuidMatch { QOF_GUID_MATCH_ANY = 1, QOF_GUID_MATCH_NONE, QOF_GUID_MATCH_NULL, QOF_GUID_MATCH_ALL, QOF_GUID_MATCH_LIST_ANY }

enum	QofCharMatch { QOF_CHAR_MATCH_ANY = 1, QOF_CHAR_MATCH_NONE }

Query Subsystem Initialization and Shudown
void	qof_query_init (void)

void	qof_query_shutdown (void)

Low-Level API Functions
QofQueryParamList *	qof_query_build_param_list (char const *param,...)

QofQuery *	qof_query_create (void)

QofQuery *	qof_query_create_for (QofIdTypeConst obj_type)

void	qof_query_destroy (QofQuery *q)

void	qof_query_search_for (QofQuery *query, QofIdTypeConst obj_type)

void	qof_query_set_book (QofQuery q, QofBook book)

void	qof_query_add_term (QofQuery query, QofQueryParamList param_list, QofQueryPredData *pred_data, QofQueryOp op)

void	qof_query_add_guid_match (QofQuery q, QofQueryParamList param_list, const GncGUID *guid, QofQueryOp op)

void	qof_query_add_guid_list_match (QofQuery q, QofQueryParamList param_list, GList *guid_list, QofGuidMatch options, QofQueryOp op)

void	qof_query_add_boolean_match (QofQuery q, QofQueryParamList param_list, gboolean value, QofQueryOp op)

GList *	qof_query_run (QofQuery *query)

GList *	qof_query_last_run (QofQuery *query)

GList *	qof_query_run_subquery (QofQuery subquery, const QofQuery primary_query)

void	qof_query_clear (QofQuery *query)

void	qof_query_purge_terms (QofQuery q, QofQueryParamList param_list)

int	qof_query_has_terms (QofQuery *q)

int	qof_query_num_terms (QofQuery *q)

gboolean	qof_query_has_term_type (QofQuery q, QofQueryParamList term_param)

GSList *	qof_query_get_term_type (QofQuery q, QofQueryParamList term_param)

QofQuery *	qof_query_copy (QofQuery *q)

QofQuery *	qof_query_invert (QofQuery *q)

QofQuery *	qof_query_merge (QofQuery q1, QofQuery q2, QofQueryOp op)

void	qof_query_merge_in_place (QofQuery q1, QofQuery q2, QofQueryOp op)

void	qof_query_set_sort_order (QofQuery q, QofQueryParamList primary_sort_params, QofQueryParamList secondary_sort_params, QofQueryParamList tertiary_sort_params)

void	qof_query_set_sort_options (QofQuery *q, gint prim_op, gint sec_op, gint tert_op)

void	qof_query_set_sort_increasing (QofQuery *q, gboolean prim_inc, gboolean sec_inc, gboolean tert_inc)

void	qof_query_set_max_results (QofQuery *q, int n)

gboolean	qof_query_equal (const QofQuery q1, const QofQuery q2)

void	qof_query_print (QofQuery *query)

QofIdType	qof_query_get_search_for (const QofQuery *q)

GList *	qof_query_get_books (QofQuery *q)

Core Data Type Predicates
QofQueryPredData *	qof_query_string_predicate (QofQueryCompare how, const gchar *str, QofStringMatch options, gboolean is_regex)

QofQueryPredData *	qof_query_date_predicate (QofQueryCompare how, QofDateMatch options, Timespec date)

QofQueryPredData *	qof_query_numeric_predicate (QofQueryCompare how, QofNumericMatch options, gnc_numeric value)

QofQueryPredData *	qof_query_guid_predicate (QofGuidMatch options, GList *guids)

QofQueryPredData *	qof_query_int32_predicate (QofQueryCompare how, gint32 val)

QofQueryPredData *	qof_query_int64_predicate (QofQueryCompare how, gint64 val)

QofQueryPredData *	qof_query_double_predicate (QofQueryCompare how, double val)

QofQueryPredData *	qof_query_boolean_predicate (QofQueryCompare how, gboolean val)

QofQueryPredData *	qof_query_char_predicate (QofCharMatch options, const gchar *chars)

QofQueryPredData *	qof_query_collect_predicate (QofGuidMatch options, QofCollection *coll)

QofQueryPredData *	qof_query_choice_predicate (QofGuidMatch options, GList *guids)

QofQueryPredData *	qof_query_kvp_predicate (QofQueryCompare how, QofQueryParamList path, const KvpValue value)

QofQueryPredData *	qof_query_kvp_predicate_path (QofQueryCompare how, const gchar path, const KvpValue value)

QofQueryPredData *	qof_query_core_predicate_copy (const QofQueryPredData *pdata)

void	qof_query_core_predicate_free (QofQueryPredData *pdata)

gboolean	qof_query_date_predicate_get_date (const QofQueryPredData pd, Timespec date)

char *	qof_query_core_to_string (QofType, gpointer object, QofParam *getter)

int	qof_string_number_compare_func (gpointer a, gpointer b, gint options, QofParam *this_param)

Detailed Description

BASIC QUERY API: With this API you can create arbitrary logical queries to find sets of arbitrary object. To make simple queries (1 term, such as a search for a parameter with one value), create the appropriate QueryTerm structure and stick it in a Query object using xaccInitQuery. The QueryTerm should be malloc'd but the Query object will handle freeing it. To make compound queries, make multiple simple queries and combine them using qof_query_merge() and the logical operations of your choice.

SQL QUERY API: As an alternative to building queries one predicate at a time, you can use the SQL query interface. This interface will accept a string containing an SQL query, parse it, convert it into the core representation, and execute it.

STRUCTURE OF A QUERY: A Query is a logical function of any number of QueryTerms. A QueryTerm consists of a C function pointer (the Predicate) and a PredicateData structure containing data passed to the predicate function. The PredicateData structure is a constant associated with the Term and is identical for every object that is tested.

The terms of the Query may represent any logical function and are stored in canonical form, i.e. the function is expressed as a logical sum of logical products. So if you have QueryTerms a, b, c, d, e and you have the logical function a(b+c) + !(c(d+e)), it gets stored as ab + ac + !c + !c!e +!d!c + !d!e. This may not be optimal for evaluation of some functions but it's easy to store, easy to manipulate, and it doesn't require a complete algebra system to deal with.

The representation is of a GList of GLists of QueryTerms. The "backbone" GList q->terms represents the OR-chain, and every item on the backbone is a GList of QueryTerms representing an AND-chain corresponding to a single product-term in the canonical representation. QueryTerms are duplicated when necessary to fill out the canonical form, and the same predicate may be evaluated multiple times per split for complex queries. This is a place where we could probably optimize.

Macro Definition Documentation

#define QOF_PARAM_BOOK "book"

"Known" Object Parameters – all objects must support these

Definition at line 109 of file qofquery.h.

#define QOF_PARAM_KVP "kvp"

"Known" Object Parameters – some objects might support these

Definition at line 113 of file qofquery.h.

#define QOF_QUERY_FIRST_TERM QOF_QUERY_AND

First/only term is same as 'and'

Definition at line 103 of file qofquery.h.

#define QUERY_DEFAULT_SORT "QofQueryDefaultSort"

Default sort object type

Definition at line 106 of file qofquery.h.

Typedef Documentation

typedef struct _QofQuery QofQuery

A Query

Definition at line 90 of file qofquery.h.

typedef GSList QofQueryParamList

A list of parameters (QofIdType) used to describe a parameter to use in a predicate or when sorting

Definition at line 152 of file qofquerycore.h.

typedef struct _QofQueryPredData QofQueryPredData

PREDICATE DATA TYPES: All the predicate data types are rolled up into the union type PredicateData. The "type" field specifies which type the union is.

Definition at line 50 of file qofquerycore.h.

Enumeration Type Documentation

enum QofCharMatch

A CHAR type is for a RECNCell, Comparisons for QOF_TYPE_CHAR 'ANY' will match any character in the string.

Match 'ANY' is a convenience/performance-enhanced predicate for the compound statement (value==char1) || (value==char2) || etc. Match 'NONE' is equivalent to (value != char1) && (value != char2) && etc.

Definition at line 133 of file qofquerycore.h.

 {
     QOF_CHAR_MATCH_ANY = 1,
     QOF_CHAR_MATCH_NONE
 } QofCharMatch;

enum QofDateMatch

Comparisons for QOF_TYPE_DATE The QOF_DATE_MATCH_DAY comparison rounds the two time values to mid-day and then compares these rounded values. The QOF_DATE_MATCH_NORMAL comparison matches the time values, down to the second.

Definition at line 84 of file qofquerycore.h.

 {
     QOF_DATE_MATCH_NORMAL = 1,
     QOF_DATE_MATCH_DAY
 } QofDateMatch;

enum QofGuidMatch

Enumerator
QOF_GUID_MATCH_ANY	These expect a single object and expect the QofAccessFunc returns GncGUID*
QOF_GUID_MATCH_ALL	These expect a GList* of objects and calls the QofAccessFunc routine on each item in the list to obtain a GncGUID* for each object
QOF_GUID_MATCH_LIST_ANY	These expect a single object and expect the QofAccessFunc function to return a GList* of GncGUID* (the list is the property of the caller)

Definition at line 110 of file qofquerycore.h.

 {
     QOF_GUID_MATCH_ANY = 1,
     QOF_GUID_MATCH_NONE,
     QOF_GUID_MATCH_NULL,
     QOF_GUID_MATCH_ALL,
     QOF_GUID_MATCH_LIST_ANY,
 } QofGuidMatch;

enum QofNumericMatch

Comparisons for QOF_TYPE_NUMERIC, QOF_TYPE_DEBCRED

XXX Should be deprecated, or at least wrapped up as a convenience function, this is based on the old bill gribble code, which assumed the amount was always positive, and then specified a funds-flow direction (credit, debit, or either).

The point being that 'match credit' is equivalent to the compound predicate (amount >= 0) && (amount 'op' value) while the 'match debit' predicate is equivalent to (amount <= 0) && (abs(amount) 'op' value)

Definition at line 102 of file qofquerycore.h.

 {
     QOF_NUMERIC_MATCH_DEBIT = 1,
     QOF_NUMERIC_MATCH_CREDIT,
     QOF_NUMERIC_MATCH_ANY
 } QofNumericMatch;

enum QofQueryCompare

Standard Query comparators, for how to compare objects in a predicate. Note that not all core types implement all comparators

Definition at line 55 of file qofquerycore.h.

 {
     QOF_COMPARE_LT = 1,
     QOF_COMPARE_LTE,
     QOF_COMPARE_EQUAL,
     QOF_COMPARE_GT,
     QOF_COMPARE_GTE,
     QOF_COMPARE_NEQ,
     QOF_COMPARE_CONTAINS,
     QOF_COMPARE_NCONTAINS
 } QofQueryCompare;

enum QofQueryOp

Query Term Operators, for combining Query Terms

Definition at line 93 of file qofquery.h.

 {
     QOF_QUERY_AND = 1,
     QOF_QUERY_OR,
     QOF_QUERY_NAND,
     QOF_QUERY_NOR,
     QOF_QUERY_XOR
 } QofQueryOp;

enum QofStringMatch

List of known core query data-types... Each core query type defines it's set of optional "comparator qualifiers".

Definition at line 71 of file qofquerycore.h.

 {
     QOF_STRING_MATCH_NORMAL = 1,
     QOF_STRING_MATCH_CASEINSENSITIVE
 } QofStringMatch;

Function Documentation

void qof_query_add_boolean_match	(	QofQuery *	q,
		QofQueryParamList *	param_list,
		gboolean	value,
		QofQueryOp	op
	)

Handy-dandy convenience routines, avoids having to create a separate predicate for boolean matches. We might want to create handy-dandy sugar routines for the other predicate types as well.

void qof_query_add_guid_list_match	(	QofQuery *	q,
		QofQueryParamList *	param_list,
		GList *	guid_list,
		QofGuidMatch	options,
		QofQueryOp	op
	)

DOCUMENT ME !!

void qof_query_add_guid_match	(	QofQuery *	q,
		QofQueryParamList *	param_list,
		const GncGUID *	guid,
		QofQueryOp	op
	)

DOCUMENT ME !!

void qof_query_add_term	(	QofQuery *	query,
		QofQueryParamList *	param_list,
		QofQueryPredData *	pred_data,
		QofQueryOp	op
	)

This is the general function that adds a new Query Term to a query. It will find the 'obj_type' object of the search item and compare the 'param_list' parameter to the predicate data via the comparator.

The param_list is a recursive list of parameters. For example, you can say 'split->memo' by creating a list of one element, "SPLIT_MEMO". You can say 'split->account->name' by creating a list of two elements, "SPLIT_ACCOUNT" and "ACCOUNT_NAME". The list becomes the property of the Query.

For example:

acct_name_pred_data = make_string_pred_data(QOF_STRING_MATCH_CASEINSENSITIVE, account_name); param_list = make_list (SPLIT_ACCOUNT, ACCOUNT_NAME, NULL); qof_query_add_term (query, param_list, QOF_COMPARE_EQUAL, acct_name_pred_data, QOF_QUERY_AND);

Please note that QofQuery does not, at this time, support joins. That is, one cannot specify a predicate that is a parameter list. Put another way, one cannot search for objects where obja->thingy == objb->stuff

void qof_query_clear ( QofQuery * query )

Remove all query terms from query. query matches nothing after qof_query_clear().

QofQuery* qof_query_copy ( QofQuery * q )

Make a copy of the indicated query

QofQueryPredData* qof_query_core_predicate_copy ( const QofQueryPredData * pdata )

Copy a predicate.

void qof_query_core_predicate_free ( QofQueryPredData * pdata )

Destroy a predicate.

char* qof_query_core_to_string	(	QofType	,
		gpointer	object,
		QofParam *	getter
	)

Return a printable string for a core data object. Caller needs to g_free() the returned string.

QofQuery* qof_query_create ( void )

Create a new query. Before running the query, a 'search-for' type must be set otherwise nothing will be returned. The results of the query is a list of the indicated search-for type.

Allocates and initializes a Query structure which must be freed by the user with qof_query_destroy(). A newly-allocated QofQuery object matches nothing (qof_query_run() will return NULL).

gboolean qof_query_date_predicate_get_date	(	const QofQueryPredData *	pd,
		Timespec *	date
	)

Retrieve a predicate.

void qof_query_destroy ( QofQuery * q )

Frees the resources associate with a Query object.

gboolean qof_query_equal	(	const QofQuery *	q1,
		const QofQuery *	q2
	)

Compare two queries for equality. Query terms are compared each to each. This is a simplistic implementation – logical equivalences between different and/or trees are ignored.

GList* qof_query_get_books ( QofQuery * q )

Return the list of books we're using

QofIdType qof_query_get_search_for ( const QofQuery * q )

Return the type of data we're querying for

gboolean qof_query_has_term_type	(	QofQuery *	q,
		QofQueryParamList *	term_param
	)

DOCUMENT ME !!

int qof_query_has_terms ( QofQuery * q )

Return boolean FALSE if there are no terms in the query Can be used as a predicate to see if the query has been initialized (return value > 0) or is "blank" (return value == 0).

void qof_query_init ( void )

Subsystem initialization and shutdown. Call init() once to initialize the query subsystem; call shutdown() to free up any resources associated with the query subsystem. Typically called during application startup, shutdown.

QofQuery* qof_query_invert ( QofQuery * q )

Make a copy of the indicated query, inverting the sense of the search. In other words, if the original query search for all objects with a certain condition, the inverted query will search for all object with NOT that condition. The union of the results returned by the original and inverted queries equals the set of all searched objects. These to sets are disjoint (share no members in common).

This will return a newly allocated QofQuery object, or NULL on error. Free it with qof_query_destroy() when no longer needed.

QofQueryPredData* qof_query_kvp_predicate	(	QofQueryCompare	how,
		QofQueryParamList *	path,
		const KvpValue *	value
	)

The qof_query_kvp_predicate() matches the object that has the value 'value' located at the path 'path'. In a certain sense, the 'path' is handled as if it were a parameter.

QofQueryPredData* qof_query_kvp_predicate_path	(	QofQueryCompare	how,
		const gchar *	path,
		const KvpValue *	value
	)

Same predicate as above, except that 'path' is assumed to be a string containing slash-separated pathname.

GList* qof_query_last_run ( QofQuery * query )

Return the results of the last query, without causing the query to be re-run. Do NOT free the resulting list. This list is managed internally by QofQuery.

QofQuery* qof_query_merge	(	QofQuery *	q1,
		QofQuery *	q2,
		QofQueryOp	op
	)

Combine two queries together using the Boolean set (logical) operator 'op'. For example, if the operator 'op' is set to QUERY_AND, then the set of results returned by the query will will be the Boolean set intersection of the results returned by q1 and q2. Similarly, QUERY_OR maps to set union, etc.

Both queries must have compatible search-types. If both queries are set, they must search for the same object type. If only one is set, the resulting query will search for the set type. If neither query has the search-type set, the result will be unset as well.

This will return a newly allocated QofQuery object, or NULL on error. Free it with qof_query_destroy() when no longer needed. Note that if either input query is NULL then the returned query is NOT newly allocated – it will return the non-NULL query. You only need to call this function when both q1 and q2 are non-NULL.

void qof_query_merge_in_place	(	QofQuery *	q1,
		QofQuery *	q2,
		QofQueryOp	op
	)

Like qof_query_merge, but this will merge a copy of q2 into q1. q2 remains unchanged.

int qof_query_num_terms ( QofQuery * q )

Return the number of terms in the canonical form of the query.

void qof_query_print ( QofQuery * query )

Log the Query

Deprecated:: Do not call directly, use the standard log module code: ::qof_log_set_level(QOF_MOD_QUERY, QOF_LOG_DEBUG); or ::qof_log_set_default(QOF_LOG_DEBUG);

void qof_query_purge_terms	(	QofQuery *	q,
		QofQueryParamList *	param_list
	)

Remove query terms of a particular type from q. The "type" of a term is determined by the type of data that gets passed to the predicate function. XXX ??? Huh? remove anything of that predicate type, or just the particular predicate ?

GList* qof_query_run ( QofQuery * query )

Perform the query, return the results. The returned list is a list of the 'search-for' type that was previously set with the qof_query_search_for() or the qof_query_create_for() routines. The returned list will have been sorted using the indicated sort order, and trimmed to the max_results length.

Do NOT free the resulting list. This list is managed internally by QofQuery.

GList* qof_query_run_subquery	(	QofQuery *	subquery,
		const QofQuery *	primary_query
	)

Perform a subquery, return the results. Instead of running over a book, the subquery runs over the results of the primary query.

Do NOT free the resulting list. This list is managed internally by QofQuery.

void qof_query_search_for	(	QofQuery *	query,
		QofIdTypeConst	obj_type
	)

Set the object type to be searched for. The results of performing the query will be a list of this obj_type.

void qof_query_set_book	(	QofQuery *	q,
		QofBook *	book
	)

Set the book to be searched. Books contain/identify collections of objects; the search will be performed over those books specified with this function. If no books are set, no results will be returned (since there is nothing to search over).

You can search multiple books. To specify multiple books, call this function multiple times with different arguments. XXX needed qof_query_clear_books() to reset the list ...

void qof_query_set_max_results	(	QofQuery *	q,
		int	n
	)

Set the maximum number of results that should be returned. If 'max-results' is set to -1, then all of the results are returned. If there are more results than 'max-results', then the result list is trimmed. Note that there is an important interplay between 'max-results' and the sort order: only the last bit of results are returned. For example, if the sort order is set to be increasing date order, then only the objects with the most recent dates will be returned.

void qof_query_set_sort_increasing	(	QofQuery *	q,
		gboolean	prim_inc,
		gboolean	sec_inc,
		gboolean	tert_inc
	)

When a query is run, the results are sorted before being returned. This routine can be used to control the direction of the ordering. A value of TRUE indicates the sort will be in increasing order, a value of FALSE will order results in decreasing order.

Note that if there are more results than the 'max-results' value, then only the last max-results will be returned. For example, if the sort is set to be increasing date order, then only the objects with the most recent dates will be returned.

void qof_query_set_sort_order	(	QofQuery *	q,
		QofQueryParamList *	primary_sort_params,
		QofQueryParamList *	secondary_sort_params,
		QofQueryParamList *	tertiary_sort_params
	)

When a query is run, the results are sorted before being returned. This routine can be used to set the parameters on which the sort will be performed. Two objects in the result list will be compared using the 'primary_sort_params', and sorted based on that order. If the comparison shows that they are equal, then the 'secondary_sort_params' will be used. If still equal, then the tertiary parameters will be compared. Any or all of these parameter lists may be NULL. Any of these parameter lists may be set to QUERY_DEFAULT_SORT.

Note that if there are more results than the 'max-results' value, then only the last max-results will be returned. For example, if the sort is set to be increasing date order, then only the objects with the most recent dates will be returned.

The input lists become the property of QofQuery and are managed by it. They will be freed when the query is destroyed (or when new lists are set).

int qof_string_number_compare_func	(	gpointer	a,
		gpointer	b,
		gint	options,
		QofParam *	this_param
	)

Compare two parameter(strings) as if they are numbers! the two objects, a and b, are the objects being compared this_param is the QofParam for this parameter in the objects

Files

Data Structures

Macros

Typedefs

Enumerations

Query Subsystem Initialization and Shudown

Low-Level API Functions

Core Data Type Predicates

Detailed Description

Macro Definition Documentation

Typedef Documentation

Enumeration Type Documentation

Function Documentation