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39 | |
40 | #include "qsqlrelationaltablemodel.h" |
41 | |
42 | #include "qhash.h" |
43 | #include "qstringlist.h" |
44 | #include "qsqldatabase.h" |
45 | #include "qsqldriver.h" |
46 | #include "qsqlerror.h" |
47 | #include "qsqlfield.h" |
48 | #include "qsqlindex.h" |
49 | #include "qsqlquery.h" |
50 | #include "qsqlrecord.h" |
51 | |
52 | #include "qsqltablemodel_p.h" |
53 | |
54 | #include "qdebug.h" |
55 | |
56 | QT_BEGIN_NAMESPACE |
57 | |
58 | class QSqlRelationalTableModelSql: public QSqlTableModelSql |
59 | { |
60 | public: |
61 | inline const static QString relTablePrefix(int i) { return QString::number(i).prepend(s: QLatin1String("relTblAl_" )); } |
62 | }; |
63 | |
64 | typedef QSqlRelationalTableModelSql Sql; |
65 | |
66 | /*! |
67 | \class QSqlRelation |
68 | \inmodule QtSql |
69 | \brief The QSqlRelation class stores information about an SQL foreign key. |
70 | |
71 | QSqlRelation is a helper class for QSqlRelationalTableModel. See |
72 | QSqlRelationalTableModel::setRelation() and |
73 | QSqlRelationalTableModel::relation() for details. |
74 | |
75 | \sa QSqlRelationalTableModel, QSqlRelationalDelegate, |
76 | {Relational Table Model Example} |
77 | */ |
78 | |
79 | /*! |
80 | \fn QSqlRelation::QSqlRelation() |
81 | |
82 | Constructs an invalid QSqlRelation object. |
83 | |
84 | For such an object, the tableName(), indexColumn(), and |
85 | displayColumn() functions return an empty string. |
86 | |
87 | \sa isValid() |
88 | */ |
89 | |
90 | /*! |
91 | \fn QSqlRelation::QSqlRelation(const QString &tableName, const QString &indexColumn, |
92 | const QString &displayColumn) |
93 | |
94 | Constructs a QSqlRelation object, where \a tableName is the SQL |
95 | table name to which a foreign key refers, \a indexColumn is the |
96 | foreign key, and \a displayColumn is the field that should be |
97 | presented to the user. |
98 | |
99 | \sa tableName(), indexColumn(), displayColumn() |
100 | */ |
101 | |
102 | /*! |
103 | \fn void QSqlRelation::swap(QSqlRelation &other) |
104 | |
105 | Swaps \c this with \a other. |
106 | */ |
107 | |
108 | /*! |
109 | \fn QString QSqlRelation::tableName() const |
110 | |
111 | Returns the name of the table to which a foreign key refers. |
112 | */ |
113 | |
114 | /*! |
115 | \fn QString QSqlRelation::indexColumn() const |
116 | |
117 | Returns the index column from table tableName() to which a |
118 | foreign key refers. |
119 | */ |
120 | |
121 | /*! |
122 | \fn QString QSqlRelation::displayColumn() const |
123 | |
124 | Returns the column from table tableName() that should be |
125 | presented to the user instead of a foreign key. |
126 | */ |
127 | |
128 | /*! |
129 | \fn bool QSqlRelation::isValid() const |
130 | |
131 | Returns \c true if the QSqlRelation object is valid; otherwise |
132 | returns \c false. |
133 | */ |
134 | |
135 | class QRelatedTableModel; |
136 | |
137 | struct QRelation |
138 | { |
139 | public: |
140 | QRelation(): model(nullptr), m_parent(nullptr), m_dictInitialized(false) {} |
141 | void init(QSqlRelationalTableModel *parent, const QSqlRelation &relation); |
142 | |
143 | void populateModel(); |
144 | |
145 | bool isDictionaryInitialized(); |
146 | void populateDictionary(); |
147 | void clearDictionary(); |
148 | |
149 | void clear(); |
150 | bool isValid(); |
151 | |
152 | QSqlRelation rel; |
153 | QRelatedTableModel *model; |
154 | QHash<QString, QVariant> dictionary;//maps keys to display values |
155 | |
156 | private: |
157 | QSqlRelationalTableModel *m_parent; |
158 | bool m_dictInitialized; |
159 | }; |
160 | |
161 | class QRelatedTableModel : public QSqlTableModel |
162 | { |
163 | public: |
164 | QRelatedTableModel(QRelation *rel, QObject *parent = nullptr, QSqlDatabase db = QSqlDatabase()); |
165 | bool select() override; |
166 | private: |
167 | bool firstSelect; |
168 | QRelation *relation; |
169 | }; |
170 | /* |
171 | A QRelation must be initialized before it is considered valid. |
172 | Note: population of the model and dictionary are kept separate |
173 | from initialization, and are populated on an as needed basis. |
174 | */ |
175 | void QRelation::init(QSqlRelationalTableModel *parent, const QSqlRelation &relation) |
176 | { |
177 | Q_ASSERT(parent != nullptr); |
178 | m_parent = parent; |
179 | rel = relation; |
180 | } |
181 | |
182 | void QRelation::populateModel() |
183 | { |
184 | if (!isValid()) |
185 | return; |
186 | Q_ASSERT(m_parent != nullptr); |
187 | |
188 | if (!model) { |
189 | model = new QRelatedTableModel(this, m_parent, m_parent->database()); |
190 | model->setTable(rel.tableName()); |
191 | model->select(); |
192 | } |
193 | } |
194 | |
195 | bool QRelation::isDictionaryInitialized() |
196 | { |
197 | return m_dictInitialized; |
198 | } |
199 | |
200 | void QRelation::populateDictionary() |
201 | { |
202 | if (!isValid()) |
203 | return; |
204 | |
205 | if (model == nullptr) |
206 | populateModel(); |
207 | |
208 | QSqlRecord record; |
209 | QString indexColumn; |
210 | QString displayColumn; |
211 | for (int i=0; i < model->rowCount(); ++i) { |
212 | record = model->record(row: i); |
213 | |
214 | indexColumn = rel.indexColumn(); |
215 | if (m_parent->database().driver()->isIdentifierEscaped(identifier: indexColumn, type: QSqlDriver::FieldName)) |
216 | indexColumn = m_parent->database().driver()->stripDelimiters(identifier: indexColumn, type: QSqlDriver::FieldName); |
217 | |
218 | displayColumn = rel.displayColumn(); |
219 | if (m_parent->database().driver()->isIdentifierEscaped(identifier: displayColumn, type: QSqlDriver::FieldName)) |
220 | displayColumn = m_parent->database().driver()->stripDelimiters(identifier: displayColumn, type: QSqlDriver::FieldName); |
221 | |
222 | dictionary[record.field(name: indexColumn).value().toString()] = |
223 | record.field(name: displayColumn).value(); |
224 | } |
225 | m_dictInitialized = true; |
226 | } |
227 | |
228 | void QRelation::clearDictionary() |
229 | { |
230 | dictionary.clear(); |
231 | m_dictInitialized = false; |
232 | } |
233 | |
234 | void QRelation::clear() |
235 | { |
236 | delete model; |
237 | model = nullptr; |
238 | clearDictionary(); |
239 | } |
240 | |
241 | bool QRelation::isValid() |
242 | { |
243 | return (rel.isValid() && m_parent != nullptr); |
244 | } |
245 | |
246 | |
247 | |
248 | QRelatedTableModel::QRelatedTableModel(QRelation *rel, QObject *parent, QSqlDatabase db) : |
249 | QSqlTableModel(parent, db), firstSelect(true), relation(rel) |
250 | { |
251 | } |
252 | |
253 | bool QRelatedTableModel::select() |
254 | { |
255 | if (firstSelect) { |
256 | firstSelect = false; |
257 | return QSqlTableModel::select(); |
258 | } |
259 | relation->clearDictionary(); |
260 | bool res = QSqlTableModel::select(); |
261 | if (res) |
262 | relation->populateDictionary(); |
263 | return res; |
264 | } |
265 | |
266 | |
267 | class QSqlRelationalTableModelPrivate: public QSqlTableModelPrivate |
268 | { |
269 | Q_DECLARE_PUBLIC(QSqlRelationalTableModel) |
270 | public: |
271 | QSqlRelationalTableModelPrivate() |
272 | : QSqlTableModelPrivate(), |
273 | joinMode( QSqlRelationalTableModel::InnerJoin ) |
274 | {} |
275 | QString fullyQualifiedFieldName(const QString &tableName, const QString &fieldName) const; |
276 | |
277 | int nameToIndex(const QString &name) const override; |
278 | mutable QVector<QRelation> relations; |
279 | QSqlRecord baseRec; // the record without relations |
280 | void clearChanges(); |
281 | void clearCache() override; |
282 | void revertCachedRow(int row) override; |
283 | |
284 | void translateFieldNames(QSqlRecord &values) const; |
285 | QSqlRelationalTableModel::JoinMode joinMode; |
286 | }; |
287 | |
288 | void QSqlRelationalTableModelPrivate::clearChanges() |
289 | { |
290 | for (int i = 0; i < relations.count(); ++i) { |
291 | QRelation &rel = relations[i]; |
292 | rel.clear(); |
293 | } |
294 | } |
295 | |
296 | void QSqlRelationalTableModelPrivate::revertCachedRow(int row) |
297 | { |
298 | QSqlTableModelPrivate::revertCachedRow(row); |
299 | } |
300 | |
301 | int QSqlRelationalTableModelPrivate::nameToIndex(const QString &name) const |
302 | { |
303 | const QString fieldname = strippedFieldName(name); |
304 | int idx = baseRec.indexOf(name: fieldname); |
305 | if (idx == -1) { |
306 | // If the name is an alias we can find it here. |
307 | idx = QSqlTableModelPrivate::nameToIndex(name); |
308 | } |
309 | return idx; |
310 | } |
311 | |
312 | void QSqlRelationalTableModelPrivate::clearCache() |
313 | { |
314 | for (int i = 0; i < relations.count(); ++i) |
315 | relations[i].clearDictionary(); |
316 | |
317 | QSqlTableModelPrivate::clearCache(); |
318 | } |
319 | |
320 | /*! |
321 | \class QSqlRelationalTableModel |
322 | \brief The QSqlRelationalTableModel class provides an editable |
323 | data model for a single database table, with foreign key support. |
324 | |
325 | \ingroup database |
326 | \inmodule QtSql |
327 | |
328 | QSqlRelationalTableModel acts like QSqlTableModel, but allows |
329 | columns to be set as foreign keys into other database tables. |
330 | |
331 | \table |
332 | \row \li \inlineimage noforeignkeys.png |
333 | \li \inlineimage foreignkeys.png |
334 | \endtable |
335 | |
336 | The screenshot on the left shows a plain QSqlTableModel in a |
337 | QTableView. Foreign keys (\c city and \c country) aren't resolved |
338 | to human-readable values. The screenshot on the right shows a |
339 | QSqlRelationalTableModel, with foreign keys resolved into |
340 | human-readable text strings. |
341 | |
342 | The following code snippet shows how the QSqlRelationalTableModel |
343 | was set up: |
344 | |
345 | \snippet relationaltablemodel/relationaltablemodel.cpp 0 |
346 | \codeline |
347 | \snippet relationaltablemodel/relationaltablemodel.cpp 1 |
348 | \snippet relationaltablemodel/relationaltablemodel.cpp 2 |
349 | |
350 | The setRelation() function calls establish a relationship between |
351 | two tables. The first call specifies that column 2 in table \c |
352 | employee is a foreign key that maps with field \c id of table \c |
353 | city, and that the view should present the \c{city}'s \c name |
354 | field to the user. The second call does something similar with |
355 | column 3. |
356 | |
357 | If you use a read-write QSqlRelationalTableModel, you probably |
358 | want to use QSqlRelationalDelegate on the view. Unlike the default |
359 | delegate, QSqlRelationalDelegate provides a combobox for fields |
360 | that are foreign keys into other tables. To use the class, simply |
361 | call QAbstractItemView::setItemDelegate() on the view with an |
362 | instance of QSqlRelationalDelegate: |
363 | |
364 | \snippet relationaltablemodel/relationaltablemodel.cpp 4 |
365 | |
366 | The \l{relationaltablemodel} example illustrates how to use |
367 | QSqlRelationalTableModel in conjunction with |
368 | QSqlRelationalDelegate to provide tables with foreign key |
369 | support. |
370 | |
371 | \image relationaltable.png |
372 | |
373 | Notes: |
374 | |
375 | \list |
376 | \li The table must have a primary key declared. |
377 | \li The table's primary key may not contain a relation to |
378 | another table. |
379 | \li If a relational table contains keys that refer to non-existent |
380 | rows in the referenced table, the rows containing the invalid |
381 | keys will not be exposed through the model. The user or the |
382 | database is responsible for keeping referential integrity. |
383 | \li If a relation's display column name is also used as a column |
384 | name in the relational table, or if it is used as display column |
385 | name in more than one relation it will be aliased. The alias is |
386 | the relation's table name, display column name and a unique id |
387 | joined by an underscore (e.g. tablename_columnname_id). |
388 | QSqlRecord::fieldName() will return the aliased column name. |
389 | All occurrences of the duplicate display column name are aliased when |
390 | duplication is detected, but no aliasing is done to the column |
391 | names in the main table. The aliasing doesn't affect |
392 | QSqlRelation, so QSqlRelation::displayColumn() will return the |
393 | original display column name. |
394 | \li The reference table name is aliased. The alias is the word "relTblAl" |
395 | and the relationed column index joined by an underscore |
396 | (e.g. relTblAl_2). The alias can be used to filter the table |
397 | (For example, setFilter("relTblAl_2='Oslo' OR |
398 | relTblAl_3='USA'")). |
399 | \li When using setData() the role should always be Qt::EditRole, |
400 | and when using data() the role should always be Qt::DisplayRole. |
401 | \endlist |
402 | |
403 | \sa QSqlRelation, QSqlRelationalDelegate, |
404 | {Relational Table Model Example} |
405 | */ |
406 | |
407 | |
408 | /*! |
409 | Creates an empty QSqlRelationalTableModel and sets the parent to \a parent |
410 | and the database connection to \a db. If \a db is not valid, the |
411 | default database connection will be used. |
412 | */ |
413 | QSqlRelationalTableModel::QSqlRelationalTableModel(QObject *parent, QSqlDatabase db) |
414 | : QSqlTableModel(*new QSqlRelationalTableModelPrivate, parent, db) |
415 | { |
416 | } |
417 | |
418 | /*! |
419 | Destroys the object and frees any allocated resources. |
420 | */ |
421 | QSqlRelationalTableModel::~QSqlRelationalTableModel() |
422 | { |
423 | } |
424 | |
425 | /*! |
426 | \reimp |
427 | */ |
428 | QVariant QSqlRelationalTableModel::data(const QModelIndex &index, int role) const |
429 | { |
430 | Q_D(const QSqlRelationalTableModel); |
431 | |
432 | if (role == Qt::DisplayRole && index.column() >= 0 && index.column() < d->relations.count() && |
433 | d->relations.value(i: index.column()).isValid()) { |
434 | QRelation &relation = d->relations[index.column()]; |
435 | if (!relation.isDictionaryInitialized()) |
436 | relation.populateDictionary(); |
437 | |
438 | //only perform a dictionary lookup for the display value |
439 | //when the value at index has been changed or added. |
440 | //At an unmodified index, the underlying model will |
441 | //already have the correct display value. |
442 | if (d->strategy != OnFieldChange) { |
443 | const QSqlTableModelPrivate::ModifiedRow row = d->cache.value(akey: index.row()); |
444 | if (row.op() != QSqlTableModelPrivate::None && row.rec().isGenerated(i: index.column())) { |
445 | if (d->strategy == OnManualSubmit || row.op() != QSqlTableModelPrivate::Delete) { |
446 | QVariant v = row.rec().value(i: index.column()); |
447 | if (v.isValid()) |
448 | return relation.dictionary[v.toString()]; |
449 | } |
450 | } |
451 | } |
452 | } |
453 | return QSqlTableModel::data(idx: index, role); |
454 | } |
455 | |
456 | /*! |
457 | Sets the data for the \a role in the item with the specified \a |
458 | index to the \a value given. Depending on the edit strategy, the |
459 | value might be applied to the database at once, or it may be |
460 | cached in the model. |
461 | |
462 | Returns \c true if the value could be set, or false on error (for |
463 | example, if \a index is out of bounds). |
464 | |
465 | For relational columns, \a value must be the index, not the |
466 | display value. The index must also exist in the referenced |
467 | table, otherwise the function returns \c false. |
468 | |
469 | \sa editStrategy(), data(), submit(), revertRow() |
470 | */ |
471 | bool QSqlRelationalTableModel::setData(const QModelIndex &index, const QVariant &value, |
472 | int role) |
473 | { |
474 | Q_D(QSqlRelationalTableModel); |
475 | if ( role == Qt::EditRole && index.column() > 0 && index.column() < d->relations.count() |
476 | && d->relations.value(i: index.column()).isValid()) { |
477 | QRelation &relation = d->relations[index.column()]; |
478 | if (!relation.isDictionaryInitialized()) |
479 | relation.populateDictionary(); |
480 | if (!relation.dictionary.contains(akey: value.toString())) |
481 | return false; |
482 | } |
483 | return QSqlTableModel::setData(index, value, role); |
484 | } |
485 | |
486 | /*! |
487 | Lets the specified \a column be a foreign index specified by \a relation. |
488 | |
489 | Example: |
490 | |
491 | \snippet relationaltablemodel/relationaltablemodel.cpp 0 |
492 | \codeline |
493 | \snippet relationaltablemodel/relationaltablemodel.cpp 1 |
494 | |
495 | The setRelation() call specifies that column 2 in table \c |
496 | employee is a foreign key that maps with field \c id of table \c |
497 | city, and that the view should present the \c{city}'s \c name |
498 | field to the user. |
499 | |
500 | Note: The table's primary key may not contain a relation to another table. |
501 | |
502 | \sa relation() |
503 | */ |
504 | void QSqlRelationalTableModel::setRelation(int column, const QSqlRelation &relation) |
505 | { |
506 | Q_D(QSqlRelationalTableModel); |
507 | if (column < 0) |
508 | return; |
509 | if (d->relations.size() <= column) |
510 | d->relations.resize(asize: column + 1); |
511 | d->relations[column].init(parent: this, relation); |
512 | } |
513 | |
514 | /*! |
515 | Returns the relation for the column \a column, or an invalid |
516 | relation if no relation is set. |
517 | |
518 | \sa setRelation(), QSqlRelation::isValid() |
519 | */ |
520 | QSqlRelation QSqlRelationalTableModel::relation(int column) const |
521 | { |
522 | Q_D(const QSqlRelationalTableModel); |
523 | return d->relations.value(i: column).rel; |
524 | } |
525 | |
526 | QString QSqlRelationalTableModelPrivate::fullyQualifiedFieldName(const QString &tableName, |
527 | const QString &fieldName) const |
528 | { |
529 | QString ret; |
530 | ret.reserve(asize: tableName.size() + fieldName.size() + 1); |
531 | ret.append(s: tableName).append(c: QLatin1Char('.')).append(s: fieldName); |
532 | |
533 | return ret; |
534 | } |
535 | |
536 | /*! |
537 | \reimp |
538 | */ |
539 | QString QSqlRelationalTableModel::selectStatement() const |
540 | { |
541 | Q_D(const QSqlRelationalTableModel); |
542 | |
543 | if (tableName().isEmpty()) |
544 | return QString(); |
545 | if (d->relations.isEmpty()) |
546 | return QSqlTableModel::selectStatement(); |
547 | |
548 | // Count how many times each field name occurs in the record |
549 | QHash<QString, int> fieldNames; |
550 | QStringList fieldList; |
551 | for (int i = 0; i < d->baseRec.count(); ++i) { |
552 | QSqlRelation relation = d->relations.value(i).rel; |
553 | QString name; |
554 | if (relation.isValid()) { |
555 | // Count the display column name, not the original foreign key |
556 | name = relation.displayColumn(); |
557 | if (d->db.driver()->isIdentifierEscaped(identifier: name, type: QSqlDriver::FieldName)) |
558 | name = d->db.driver()->stripDelimiters(identifier: name, type: QSqlDriver::FieldName); |
559 | |
560 | const QSqlRecord rec = database().record(tablename: relation.tableName()); |
561 | for (int i = 0; i < rec.count(); ++i) { |
562 | if (name.compare(s: rec.fieldName(i), cs: Qt::CaseInsensitive) == 0) { |
563 | name = rec.fieldName(i); |
564 | break; |
565 | } |
566 | } |
567 | } |
568 | else { |
569 | name = d->baseRec.fieldName(i); |
570 | } |
571 | fieldNames[name] = fieldNames.value(akey: name, adefaultValue: 0) + 1; |
572 | fieldList.append(t: name); |
573 | } |
574 | |
575 | QString fList; |
576 | QString conditions; |
577 | QString from = Sql::from(s: tableName()); |
578 | for (int i = 0; i < d->baseRec.count(); ++i) { |
579 | QSqlRelation relation = d->relations.value(i).rel; |
580 | const QString tableField = d->fullyQualifiedFieldName(tableName: tableName(), fieldName: d->db.driver()->escapeIdentifier(identifier: d->baseRec.fieldName(i), type: QSqlDriver::FieldName)); |
581 | if (relation.isValid()) { |
582 | const QString relTableAlias = Sql::relTablePrefix(i); |
583 | QString displayTableField = d->fullyQualifiedFieldName(tableName: relTableAlias, fieldName: relation.displayColumn()); |
584 | |
585 | // Duplicate field names must be aliased |
586 | if (fieldNames.value(akey: fieldList[i]) > 1) { |
587 | QString relTableName = relation.tableName().section(asep: QChar::fromLatin1(c: '.'), astart: -1, aend: -1); |
588 | if (d->db.driver()->isIdentifierEscaped(identifier: relTableName, type: QSqlDriver::TableName)) |
589 | relTableName = d->db.driver()->stripDelimiters(identifier: relTableName, type: QSqlDriver::TableName); |
590 | QString displayColumn = relation.displayColumn(); |
591 | if (d->db.driver()->isIdentifierEscaped(identifier: displayColumn, type: QSqlDriver::FieldName)) |
592 | displayColumn = d->db.driver()->stripDelimiters(identifier: displayColumn, type: QSqlDriver::FieldName); |
593 | const QString alias = QString::fromLatin1(str: "%1_%2_%3" ) |
594 | .arg(args&: relTableName, args&: displayColumn, args: QString::number(fieldNames.value(akey: fieldList[i]))); |
595 | displayTableField = Sql::as(a: displayTableField, b: alias); |
596 | --fieldNames[fieldList[i]]; |
597 | } |
598 | |
599 | fList = Sql::comma(a: fList, b: displayTableField); |
600 | |
601 | // Join related table |
602 | const QString tblexpr = Sql::concat(a: relation.tableName(), b: relTableAlias); |
603 | const QString relTableField = d->fullyQualifiedFieldName(tableName: relTableAlias, fieldName: relation.indexColumn()); |
604 | const QString cond = Sql::eq(a: tableField, b: relTableField); |
605 | if (d->joinMode == QSqlRelationalTableModel::InnerJoin) { |
606 | // FIXME: InnerJoin code is known to be broken. |
607 | // Use LeftJoin mode if you want correct behavior. |
608 | from = Sql::comma(a: from, b: tblexpr); |
609 | conditions = Sql::et(a: conditions, b: cond); |
610 | } else { |
611 | from = Sql::concat(a: from, b: Sql::leftJoin(s: tblexpr)); |
612 | from = Sql::concat(a: from, b: Sql::on(s: cond)); |
613 | } |
614 | } else { |
615 | fList = Sql::comma(a: fList, b: tableField); |
616 | } |
617 | } |
618 | |
619 | if (fList.isEmpty()) |
620 | return QString(); |
621 | |
622 | const QString stmt = Sql::concat(a: Sql::select(s: fList), b: from); |
623 | const QString where = Sql::where(s: Sql::et(a: Sql::paren(s: conditions), b: Sql::paren(s: filter()))); |
624 | return Sql::concat(a: Sql::concat(a: stmt, b: where), b: orderByClause()); |
625 | } |
626 | |
627 | /*! |
628 | Returns a QSqlTableModel object for accessing the table for which |
629 | \a column is a foreign key, or \nullptr if there is no relation for |
630 | the given \a column. |
631 | |
632 | The returned object is owned by the QSqlRelationalTableModel. |
633 | |
634 | \sa setRelation(), relation() |
635 | */ |
636 | QSqlTableModel *QSqlRelationalTableModel::relationModel(int column) const |
637 | { |
638 | Q_D(const QSqlRelationalTableModel); |
639 | if (column < 0 || column >= d->relations.count()) |
640 | return nullptr; |
641 | |
642 | QRelation &relation = const_cast<QSqlRelationalTableModelPrivate *>(d)->relations[column]; |
643 | if (!relation.isValid()) |
644 | return nullptr; |
645 | |
646 | if (!relation.model) |
647 | relation.populateModel(); |
648 | return relation.model; |
649 | } |
650 | |
651 | /*! |
652 | \reimp |
653 | */ |
654 | void QSqlRelationalTableModel::revertRow(int row) |
655 | { |
656 | QSqlTableModel::revertRow(row); |
657 | } |
658 | |
659 | /*! |
660 | \reimp |
661 | */ |
662 | void QSqlRelationalTableModel::clear() |
663 | { |
664 | Q_D(QSqlRelationalTableModel); |
665 | beginResetModel(); |
666 | d->clearChanges(); |
667 | d->relations.clear(); |
668 | QSqlTableModel::clear(); |
669 | endResetModel(); |
670 | } |
671 | |
672 | |
673 | /*! \enum QSqlRelationalTableModel::JoinMode |
674 | |
675 | \value InnerJoin - Inner join mode, return rows when there is at least one match in both tables. |
676 | \value LeftJoin - Left join mode, returns all rows from the left table (table_name1), even if there are no matches in the right table (table_name2). |
677 | |
678 | \sa QSqlRelationalTableModel::setJoinMode() |
679 | \since 4.8 |
680 | */ |
681 | |
682 | /*! |
683 | Sets the SQL \a joinMode to show or hide rows with NULL foreign keys. |
684 | In InnerJoin mode (the default) these rows will not be shown: use the |
685 | LeftJoin mode if you want to show them. |
686 | |
687 | \sa QSqlRelationalTableModel::JoinMode |
688 | \since 4.8 |
689 | */ |
690 | void QSqlRelationalTableModel::setJoinMode( QSqlRelationalTableModel::JoinMode joinMode ) |
691 | { |
692 | Q_D(QSqlRelationalTableModel); |
693 | d->joinMode = joinMode; |
694 | } |
695 | /*! |
696 | \reimp |
697 | */ |
698 | bool QSqlRelationalTableModel::select() |
699 | { |
700 | return QSqlTableModel::select(); |
701 | } |
702 | |
703 | /*! |
704 | \reimp |
705 | */ |
706 | void QSqlRelationalTableModel::setTable(const QString &table) |
707 | { |
708 | Q_D(QSqlRelationalTableModel); |
709 | |
710 | // memorize the table before applying the relations |
711 | d->baseRec = d->db.record(tablename: table); |
712 | |
713 | QSqlTableModel::setTable(table); |
714 | } |
715 | |
716 | /*! \internal |
717 | */ |
718 | void QSqlRelationalTableModelPrivate::translateFieldNames(QSqlRecord &values) const |
719 | { |
720 | for (int i = 0; i < values.count(); ++i) { |
721 | if (relations.value(i).isValid()) { |
722 | QVariant v = values.value(i); |
723 | bool gen = values.isGenerated(i); |
724 | values.replace(pos: i, field: baseRec.field(i)); |
725 | values.setValue(i, val: v); |
726 | values.setGenerated(i, generated: gen); |
727 | } |
728 | } |
729 | } |
730 | |
731 | /*! |
732 | \reimp |
733 | */ |
734 | bool QSqlRelationalTableModel::updateRowInTable(int row, const QSqlRecord &values) |
735 | { |
736 | Q_D(QSqlRelationalTableModel); |
737 | |
738 | QSqlRecord rec = values; |
739 | d->translateFieldNames(values&: rec); |
740 | |
741 | return QSqlTableModel::updateRowInTable(row, values: rec); |
742 | } |
743 | |
744 | /*! |
745 | \reimp |
746 | */ |
747 | bool QSqlRelationalTableModel::insertRowIntoTable(const QSqlRecord &values) |
748 | { |
749 | Q_D(QSqlRelationalTableModel); |
750 | |
751 | QSqlRecord rec = values; |
752 | d->translateFieldNames(values&: rec); |
753 | |
754 | return QSqlTableModel::insertRowIntoTable(values: rec); |
755 | } |
756 | |
757 | /*! |
758 | \reimp |
759 | */ |
760 | QString QSqlRelationalTableModel::orderByClause() const |
761 | { |
762 | Q_D(const QSqlRelationalTableModel); |
763 | |
764 | const QSqlRelation rel = d->relations.value(i: d->sortColumn).rel; |
765 | if (!rel.isValid()) |
766 | return QSqlTableModel::orderByClause(); |
767 | |
768 | QString f = d->fullyQualifiedFieldName(tableName: Sql::relTablePrefix(i: d->sortColumn), fieldName: rel.displayColumn()); |
769 | f = d->sortOrder == Qt::AscendingOrder ? Sql::asc(s: f) : Sql::desc(s: f); |
770 | return Sql::orderBy(s: f); |
771 | } |
772 | |
773 | /*! |
774 | \reimp |
775 | */ |
776 | bool QSqlRelationalTableModel::removeColumns(int column, int count, const QModelIndex &parent) |
777 | { |
778 | Q_D(QSqlRelationalTableModel); |
779 | |
780 | if (parent.isValid() || column < 0 || column + count > d->rec.count()) |
781 | return false; |
782 | |
783 | for (int i = 0; i < count; ++i) { |
784 | d->baseRec.remove(pos: column); |
785 | if (d->relations.count() > column) |
786 | d->relations.remove(i: column); |
787 | } |
788 | return QSqlTableModel::removeColumns(column, count, parent); |
789 | } |
790 | |
791 | QT_END_NAMESPACE |
792 | |