1 | // Copyright (C) 2016 The Qt Company Ltd. |
2 | // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only |
3 | |
4 | #include "qsqlrelationaltablemodel.h" |
5 | |
6 | #include "qhash.h" |
7 | #include "qstringlist.h" |
8 | #include "qsqldatabase.h" |
9 | #include "qsqldriver.h" |
10 | #include "qsqlerror.h" |
11 | #include "qsqlfield.h" |
12 | #include "qsqlindex.h" |
13 | #include "qsqlquery.h" |
14 | #include "qsqlrecord.h" |
15 | |
16 | #include "qsqltablemodel_p.h" |
17 | |
18 | #include "qdebug.h" |
19 | |
20 | QT_BEGIN_NAMESPACE |
21 | |
22 | using namespace Qt::StringLiterals; |
23 | |
24 | class QSqlRelationalTableModelSql: public QSqlQueryModelSql |
25 | { |
26 | public: |
27 | inline const static QString relTablePrefix(int i) { return QString::number(i).prepend(s: "relTblAl_"_L1 ); } |
28 | }; |
29 | |
30 | using SqlrTm = QSqlRelationalTableModelSql; |
31 | |
32 | /*! |
33 | \class QSqlRelation |
34 | \inmodule QtSql |
35 | \brief The QSqlRelation class stores information about an SQL foreign key. |
36 | |
37 | QSqlRelation is a helper class for QSqlRelationalTableModel. See |
38 | QSqlRelationalTableModel::setRelation() and |
39 | QSqlRelationalTableModel::relation() for details. |
40 | |
41 | \sa QSqlRelationalTableModel, QSqlRelationalDelegate, |
42 | {Relational Table Model Example} |
43 | */ |
44 | |
45 | /*! |
46 | \fn QSqlRelation::QSqlRelation() |
47 | |
48 | Constructs an invalid QSqlRelation object. |
49 | |
50 | For such an object, the tableName(), indexColumn(), and |
51 | displayColumn() functions return an empty string. |
52 | |
53 | \sa isValid() |
54 | */ |
55 | |
56 | /*! |
57 | \fn QSqlRelation::QSqlRelation(const QString &tableName, const QString &indexColumn, |
58 | const QString &displayColumn) |
59 | |
60 | Constructs a QSqlRelation object, where \a tableName is the SQL |
61 | table name to which a foreign key refers, \a indexColumn is the |
62 | foreign key, and \a displayColumn is the field that should be |
63 | presented to the user. |
64 | |
65 | \sa tableName(), indexColumn(), displayColumn() |
66 | */ |
67 | |
68 | /*! |
69 | \fn void QSqlRelation::swap(QSqlRelation &other) |
70 | \memberswap{relation} |
71 | */ |
72 | |
73 | /*! |
74 | \fn QString QSqlRelation::tableName() const |
75 | |
76 | Returns the name of the table to which a foreign key refers. |
77 | */ |
78 | |
79 | /*! |
80 | \fn QString QSqlRelation::indexColumn() const |
81 | |
82 | Returns the index column from table tableName() to which a |
83 | foreign key refers. |
84 | */ |
85 | |
86 | /*! |
87 | \fn QString QSqlRelation::displayColumn() const |
88 | |
89 | Returns the column from table tableName() that should be |
90 | presented to the user instead of a foreign key. |
91 | */ |
92 | |
93 | /*! |
94 | \fn bool QSqlRelation::isValid() const |
95 | |
96 | Returns \c true if the QSqlRelation object is valid; otherwise |
97 | returns \c false. |
98 | */ |
99 | |
100 | class QRelatedTableModel; |
101 | |
102 | struct QRelation |
103 | { |
104 | public: |
105 | Q_DISABLE_COPY(QRelation) // QRelatedTableModel stores a pointer to this class |
106 | QRelation() = default; |
107 | void init(QSqlRelationalTableModel *parent, const QSqlRelation &relation, int column); |
108 | |
109 | void populateModel(); |
110 | |
111 | bool isDictionaryInitialized() const; |
112 | void populateDictionary(); |
113 | void clearDictionary(); |
114 | |
115 | void clear(); |
116 | bool isValid() const; |
117 | |
118 | QSqlRelation rel; |
119 | QRelatedTableModel *model = nullptr; |
120 | QHash<QString, QVariant> dictionary;//maps keys to display values |
121 | |
122 | private: |
123 | QSqlRelationalTableModel *m_parent = nullptr; |
124 | int col = -1; |
125 | bool m_dictInitialized = false; |
126 | }; |
127 | |
128 | class QRelatedTableModel : public QSqlTableModel |
129 | { |
130 | public: |
131 | QRelatedTableModel(QRelation *rel, QObject *parent, const QSqlDatabase &db); |
132 | bool select() override; |
133 | private: |
134 | bool firstSelect; |
135 | QRelation *relation; |
136 | }; |
137 | /* |
138 | A QRelation must be initialized before it is considered valid. |
139 | Note: population of the model and dictionary are kept separate |
140 | from initialization, and are populated on an as needed basis. |
141 | */ |
142 | void QRelation::init(QSqlRelationalTableModel *parent, const QSqlRelation &relation, int column) |
143 | { |
144 | Q_ASSERT(parent != nullptr); |
145 | m_parent = parent; |
146 | rel = relation; |
147 | col = column; |
148 | } |
149 | |
150 | void QRelation::populateModel() |
151 | { |
152 | if (!isValid()) |
153 | return; |
154 | Q_ASSERT(m_parent != nullptr); |
155 | |
156 | if (!model) { |
157 | model = new QRelatedTableModel(this, m_parent, m_parent->database()); |
158 | model->setTable(rel.tableName()); |
159 | model->select(); |
160 | QObject::connect(sender: model, signal: &QAbstractItemModel::dataChanged, context: model, slot: [&](const QModelIndex &tl, const QModelIndex &br) |
161 | { |
162 | if (tl.column() >= col && br.column() <= col) |
163 | clearDictionary(); |
164 | }); |
165 | QObject::connect(sender: model, signal: &QAbstractItemModel::rowsRemoved, context: model, slot: [&]() |
166 | { |
167 | clearDictionary(); |
168 | }); |
169 | QObject::connect(sender: model, signal: &QAbstractItemModel::rowsInserted, context: model, slot: [&]() |
170 | { |
171 | clearDictionary(); |
172 | }); |
173 | } |
174 | } |
175 | |
176 | bool QRelation::isDictionaryInitialized() const |
177 | { |
178 | return m_dictInitialized; |
179 | } |
180 | |
181 | void QRelation::populateDictionary() |
182 | { |
183 | if (!isValid()) |
184 | return; |
185 | |
186 | if (model == nullptr) |
187 | populateModel(); |
188 | |
189 | QSqlRecord record; |
190 | QString indexColumn; |
191 | QString displayColumn; |
192 | for (int i=0; i < model->rowCount(); ++i) { |
193 | record = model->record(row: i); |
194 | |
195 | indexColumn = rel.indexColumn(); |
196 | if (m_parent->database().driver()->isIdentifierEscaped(identifier: indexColumn, type: QSqlDriver::FieldName)) |
197 | indexColumn = m_parent->database().driver()->stripDelimiters(identifier: indexColumn, type: QSqlDriver::FieldName); |
198 | |
199 | displayColumn = rel.displayColumn(); |
200 | if (m_parent->database().driver()->isIdentifierEscaped(identifier: displayColumn, type: QSqlDriver::FieldName)) |
201 | displayColumn = m_parent->database().driver()->stripDelimiters(identifier: displayColumn, type: QSqlDriver::FieldName); |
202 | |
203 | dictionary[record.field(name: indexColumn).value().toString()] = |
204 | record.field(name: displayColumn).value(); |
205 | } |
206 | m_dictInitialized = true; |
207 | } |
208 | |
209 | void QRelation::clearDictionary() |
210 | { |
211 | dictionary.clear(); |
212 | m_dictInitialized = false; |
213 | } |
214 | |
215 | void QRelation::clear() |
216 | { |
217 | delete model; |
218 | model = nullptr; |
219 | clearDictionary(); |
220 | } |
221 | |
222 | bool QRelation::isValid() const |
223 | { |
224 | return (rel.isValid() && m_parent != nullptr); |
225 | } |
226 | |
227 | |
228 | |
229 | QRelatedTableModel::QRelatedTableModel(QRelation *rel, QObject *parent, const QSqlDatabase &db) : |
230 | QSqlTableModel(parent, db), firstSelect(true), relation(rel) |
231 | { |
232 | } |
233 | |
234 | bool QRelatedTableModel::select() |
235 | { |
236 | if (firstSelect) { |
237 | firstSelect = false; |
238 | return QSqlTableModel::select(); |
239 | } |
240 | relation->clearDictionary(); |
241 | bool res = QSqlTableModel::select(); |
242 | if (res) |
243 | relation->populateDictionary(); |
244 | return res; |
245 | } |
246 | |
247 | |
248 | class QSqlRelationalTableModelPrivate: public QSqlTableModelPrivate |
249 | { |
250 | Q_DECLARE_PUBLIC(QSqlRelationalTableModel) |
251 | public: |
252 | QSqlRelationalTableModelPrivate() |
253 | : QSqlTableModelPrivate(), |
254 | joinMode( QSqlRelationalTableModel::InnerJoin ) |
255 | {} |
256 | QString fullyQualifiedFieldName(const QString &tableName, const QString &fieldName) const; |
257 | |
258 | int nameToIndex(const QString &name) const override; |
259 | QList<QSharedPointer<QRelation>> relations; |
260 | QSqlRecord baseRec; // the record without relations |
261 | void clearChanges(); |
262 | void clearCache() override; |
263 | void revertCachedRow(int row) override; |
264 | |
265 | void translateFieldNames(QSqlRecord &values) const; |
266 | QSqlRelationalTableModel::JoinMode joinMode; |
267 | }; |
268 | |
269 | void QSqlRelationalTableModelPrivate::clearChanges() |
270 | { |
271 | for (auto &rel : relations) |
272 | rel->clear(); |
273 | } |
274 | |
275 | void QSqlRelationalTableModelPrivate::revertCachedRow(int row) |
276 | { |
277 | QSqlTableModelPrivate::revertCachedRow(row); |
278 | } |
279 | |
280 | int QSqlRelationalTableModelPrivate::nameToIndex(const QString &name) const |
281 | { |
282 | const QString fieldname = strippedFieldName(name); |
283 | int idx = baseRec.indexOf(name: fieldname); |
284 | if (idx == -1) { |
285 | // If the name is an alias we can find it here. |
286 | idx = QSqlTableModelPrivate::nameToIndex(name); |
287 | } |
288 | return idx; |
289 | } |
290 | |
291 | void QSqlRelationalTableModelPrivate::clearCache() |
292 | { |
293 | for (auto &rel : relations) |
294 | rel->clearDictionary(); |
295 | |
296 | QSqlTableModelPrivate::clearCache(); |
297 | } |
298 | |
299 | /*! |
300 | \class QSqlRelationalTableModel |
301 | \brief The QSqlRelationalTableModel class provides an editable |
302 | data model for a single database table, with foreign key support. |
303 | |
304 | \ingroup database |
305 | \inmodule QtSql |
306 | |
307 | QSqlRelationalTableModel acts like QSqlTableModel, but allows |
308 | columns to be set as foreign keys into other database tables. |
309 | |
310 | \table |
311 | \row \li \inlineimage noforeignkeys.png |
312 | \li \inlineimage foreignkeys.png |
313 | \endtable |
314 | |
315 | The screenshot on the left shows a plain QSqlTableModel in a |
316 | QTableView. Foreign keys (\c city and \c country) aren't resolved |
317 | to human-readable values. The screenshot on the right shows a |
318 | QSqlRelationalTableModel, with foreign keys resolved into |
319 | human-readable text strings. |
320 | |
321 | The following code snippet shows how the QSqlRelationalTableModel |
322 | was set up: |
323 | |
324 | \snippet relationaltablemodel/relationaltablemodel.cpp 0 |
325 | \codeline |
326 | \snippet relationaltablemodel/relationaltablemodel.cpp 1 |
327 | \snippet relationaltablemodel/relationaltablemodel.cpp 2 |
328 | |
329 | The setRelation() function calls establish a relationship between |
330 | two tables. The first call specifies that column 2 in table \c |
331 | employee is a foreign key that maps with field \c id of table \c |
332 | city, and that the view should present the \c{city}'s \c name |
333 | field to the user. The second call does something similar with |
334 | column 3. |
335 | |
336 | If you use a read-write QSqlRelationalTableModel, you probably |
337 | want to use QSqlRelationalDelegate on the view. Unlike the default |
338 | delegate, QSqlRelationalDelegate provides a combobox for fields |
339 | that are foreign keys into other tables. To use the class, simply |
340 | call QAbstractItemView::setItemDelegate() on the view with an |
341 | instance of QSqlRelationalDelegate: |
342 | |
343 | \snippet relationaltablemodel/relationaltablemodel.cpp 4 |
344 | |
345 | The \l{relationaltablemodel} example illustrates how to use |
346 | QSqlRelationalTableModel in conjunction with |
347 | QSqlRelationalDelegate to provide tables with foreign key |
348 | support. |
349 | |
350 | \image relationaltable.png |
351 | |
352 | Notes: |
353 | |
354 | \list |
355 | \li The table must have a primary key declared. |
356 | \li The table's primary key may not contain a relation to |
357 | another table. |
358 | \li If a relational table contains keys that refer to non-existent |
359 | rows in the referenced table, the rows containing the invalid |
360 | keys will not be exposed through the model. The user or the |
361 | database is responsible for keeping referential integrity. |
362 | \li If a relation's display column name is also used as a column |
363 | name in the relational table, or if it is used as display column |
364 | name in more than one relation it will be aliased. The alias is |
365 | the relation's table name, display column name and a unique id |
366 | joined by an underscore (e.g. tablename_columnname_id). |
367 | QSqlRecord::fieldName() will return the aliased column name. |
368 | All occurrences of the duplicate display column name are aliased when |
369 | duplication is detected, but no aliasing is done to the column |
370 | names in the main table. The aliasing doesn't affect |
371 | QSqlRelation, so QSqlRelation::displayColumn() will return the |
372 | original display column name. |
373 | \li The reference table name is aliased. The alias is the word "relTblAl" |
374 | and the relationed column index joined by an underscore |
375 | (e.g. relTblAl_2). The alias can be used to filter the table |
376 | (For example, setFilter("relTblAl_2='Oslo' OR |
377 | relTblAl_3='USA'")). |
378 | \li When using setData() the role should always be Qt::EditRole, |
379 | and when using data() the role should always be Qt::DisplayRole. |
380 | \endlist |
381 | |
382 | \sa QSqlRelation, QSqlRelationalDelegate, |
383 | {Relational Table Model Example} |
384 | */ |
385 | |
386 | |
387 | /*! |
388 | Creates an empty QSqlRelationalTableModel and sets the parent to \a parent |
389 | and the database connection to \a db. If \a db is not valid, the |
390 | default database connection will be used. |
391 | */ |
392 | QSqlRelationalTableModel::QSqlRelationalTableModel(QObject *parent, const QSqlDatabase &db) |
393 | : QSqlTableModel(*new QSqlRelationalTableModelPrivate, parent, db) |
394 | { |
395 | } |
396 | |
397 | /*! |
398 | Destroys the object and frees any allocated resources. |
399 | */ |
400 | QSqlRelationalTableModel::~QSqlRelationalTableModel() |
401 | { |
402 | } |
403 | |
404 | /*! |
405 | \reimp |
406 | */ |
407 | QVariant QSqlRelationalTableModel::data(const QModelIndex &index, int role) const |
408 | { |
409 | Q_D(const QSqlRelationalTableModel); |
410 | |
411 | if (role == Qt::DisplayRole && index.column() >= 0 && index.column() < d->relations.size() && |
412 | d->relations.at(i: index.column())->isValid()) { |
413 | auto relation = d->relations.at(i: index.column()); |
414 | if (!relation->isDictionaryInitialized()) |
415 | relation->populateDictionary(); |
416 | |
417 | //only perform a dictionary lookup for the display value |
418 | //when the value at index has been changed or added. |
419 | //At an unmodified index, the underlying model will |
420 | //already have the correct display value. |
421 | if (d->strategy != OnFieldChange) { |
422 | const QSqlTableModelPrivate::ModifiedRow row = d->cache.value(key: index.row()); |
423 | if (row.op() != QSqlTableModelPrivate::None && row.rec().isGenerated(i: index.column())) { |
424 | if (d->strategy == OnManualSubmit || row.op() != QSqlTableModelPrivate::Delete) { |
425 | QVariant v = row.rec().value(i: index.column()); |
426 | if (v.isValid()) |
427 | return relation->dictionary[v.toString()]; |
428 | } |
429 | } |
430 | } |
431 | } |
432 | return QSqlTableModel::data(idx: index, role); |
433 | } |
434 | |
435 | /*! |
436 | Sets the data for the \a role in the item with the specified \a |
437 | index to the \a value given. Depending on the edit strategy, the |
438 | value might be applied to the database at once, or it may be |
439 | cached in the model. |
440 | |
441 | Returns \c true if the value could be set, or false on error (for |
442 | example, if \a index is out of bounds). |
443 | |
444 | For relational columns, \a value must be the index, not the |
445 | display value. The index must also exist in the referenced |
446 | table, otherwise the function returns \c false. |
447 | |
448 | \sa editStrategy(), data(), submit(), revertRow() |
449 | */ |
450 | bool QSqlRelationalTableModel::setData(const QModelIndex &index, const QVariant &value, |
451 | int role) |
452 | { |
453 | Q_D(QSqlRelationalTableModel); |
454 | if ( role == Qt::EditRole && index.column() > 0 && index.column() < d->relations.size() |
455 | && d->relations.at(i: index.column())->isValid()) { |
456 | auto relation = d->relations.at(i: index.column()); |
457 | if (!relation->isDictionaryInitialized()) |
458 | relation->populateDictionary(); |
459 | if (!relation->dictionary.contains(key: value.toString())) |
460 | return false; |
461 | } |
462 | return QSqlTableModel::setData(index, value, role); |
463 | } |
464 | |
465 | /*! |
466 | Lets the specified \a column be a foreign index specified by \a relation. |
467 | |
468 | Example: |
469 | |
470 | \snippet relationaltablemodel/relationaltablemodel.cpp 0 |
471 | \codeline |
472 | \snippet relationaltablemodel/relationaltablemodel.cpp 1 |
473 | |
474 | The setRelation() call specifies that column 2 in table \c |
475 | employee is a foreign key that maps with field \c id of table \c |
476 | city, and that the view should present the \c{city}'s \c name |
477 | field to the user. |
478 | |
479 | Note: The table's primary key may not contain a relation to another table. |
480 | |
481 | \sa relation() |
482 | */ |
483 | void QSqlRelationalTableModel::setRelation(int column, const QSqlRelation &relation) |
484 | { |
485 | Q_D(QSqlRelationalTableModel); |
486 | if (column < 0) |
487 | return; |
488 | if (d->relations.size() <= column) { |
489 | const auto oldSize = d->relations.size(); |
490 | d->relations.resize(size: column + 1); |
491 | for (auto i = oldSize; i < d->relations.size(); ++i) |
492 | d->relations[i] = QSharedPointer<QRelation>::create(); |
493 | } |
494 | d->relations.at(i: column)->init(parent: this, relation, column); |
495 | } |
496 | |
497 | /*! |
498 | Returns the relation for the column \a column, or an invalid |
499 | relation if no relation is set. |
500 | |
501 | \sa setRelation(), QSqlRelation::isValid() |
502 | */ |
503 | QSqlRelation QSqlRelationalTableModel::relation(int column) const |
504 | { |
505 | Q_D(const QSqlRelationalTableModel); |
506 | return d->relations.value(i: column) ? d->relations.at(i: column)->rel : QSqlRelation(); |
507 | } |
508 | |
509 | QString QSqlRelationalTableModelPrivate::fullyQualifiedFieldName(const QString &tableName, |
510 | const QString &fieldName) const |
511 | { |
512 | QString ret; |
513 | ret.reserve(asize: tableName.size() + fieldName.size() + 1); |
514 | ret.append(s: tableName).append(c: u'.').append(s: fieldName); |
515 | |
516 | return ret; |
517 | } |
518 | |
519 | /*! |
520 | \reimp |
521 | */ |
522 | QString QSqlRelationalTableModel::selectStatement() const |
523 | { |
524 | Q_D(const QSqlRelationalTableModel); |
525 | |
526 | if (tableName().isEmpty()) |
527 | return QString(); |
528 | if (d->relations.isEmpty()) |
529 | return QSqlTableModel::selectStatement(); |
530 | |
531 | // Count how many times each field name occurs in the record |
532 | QHash<QString, int> fieldNames; |
533 | QStringList fieldList; |
534 | for (int i = 0; i < d->baseRec.count(); ++i) { |
535 | QSqlRelation relation = d->relations.value(i) ? d->relations.at(i)->rel : QSqlRelation(); |
536 | QString name; |
537 | if (relation.isValid()) { |
538 | // Count the display column name, not the original foreign key |
539 | name = relation.displayColumn(); |
540 | if (d->db.driver()->isIdentifierEscaped(identifier: name, type: QSqlDriver::FieldName)) |
541 | name = d->db.driver()->stripDelimiters(identifier: name, type: QSqlDriver::FieldName); |
542 | |
543 | const QSqlRecord rec = database().record(tablename: relation.tableName()); |
544 | for (int i = 0; i < rec.count(); ++i) { |
545 | if (name.compare(s: rec.fieldName(i), cs: Qt::CaseInsensitive) == 0) { |
546 | name = rec.fieldName(i); |
547 | break; |
548 | } |
549 | } |
550 | } |
551 | else { |
552 | name = d->baseRec.fieldName(i); |
553 | } |
554 | fieldNames[name] = fieldNames.value(key: name, defaultValue: 0) + 1; |
555 | fieldList.append(t: name); |
556 | } |
557 | |
558 | QString fList; |
559 | QString conditions; |
560 | QString from = SqlrTm::from(s: tableName()); |
561 | for (int i = 0; i < d->baseRec.count(); ++i) { |
562 | QSqlRelation relation = d->relations.value(i) ? d->relations.at(i)->rel : QSqlRelation(); |
563 | const QString tableField = d->fullyQualifiedFieldName(tableName: tableName(), fieldName: d->db.driver()->escapeIdentifier(identifier: d->baseRec.fieldName(i), type: QSqlDriver::FieldName)); |
564 | if (relation.isValid()) { |
565 | const QString relTableAlias = SqlrTm::relTablePrefix(i); |
566 | QString displayTableField = d->fullyQualifiedFieldName(tableName: relTableAlias, fieldName: relation.displayColumn()); |
567 | |
568 | // Duplicate field names must be aliased |
569 | if (fieldNames.value(key: fieldList[i]) > 1) { |
570 | QString relTableName = relation.tableName().section(asep: QChar::fromLatin1(c: '.'), astart: -1, aend: -1); |
571 | if (d->db.driver()->isIdentifierEscaped(identifier: relTableName, type: QSqlDriver::TableName)) |
572 | relTableName = d->db.driver()->stripDelimiters(identifier: relTableName, type: QSqlDriver::TableName); |
573 | QString displayColumn = relation.displayColumn(); |
574 | if (d->db.driver()->isIdentifierEscaped(identifier: displayColumn, type: QSqlDriver::FieldName)) |
575 | displayColumn = d->db.driver()->stripDelimiters(identifier: displayColumn, type: QSqlDriver::FieldName); |
576 | QString alias = QString::fromLatin1(ba: "%1_%2_%3" ) |
577 | .arg(args&: relTableName, args&: displayColumn, args: QString::number(fieldNames.value(key: fieldList[i]))); |
578 | alias.truncate(pos: d->db.driver()->maximumIdentifierLength(type: QSqlDriver::FieldName)); |
579 | alias = d->db.driver()->escapeIdentifier(identifier: alias, type: QSqlDriver::FieldName); |
580 | displayTableField = SqlrTm::as(a: displayTableField, b: alias); |
581 | --fieldNames[fieldList[i]]; |
582 | } |
583 | |
584 | fList = SqlrTm::comma(a: fList, b: displayTableField); |
585 | |
586 | // Join related table |
587 | const QString tblexpr = SqlrTm::concat(a: relation.tableName(), b: relTableAlias); |
588 | const QString relTableField = d->fullyQualifiedFieldName(tableName: relTableAlias, fieldName: relation.indexColumn()); |
589 | const QString cond = SqlrTm::eq(a: tableField, b: relTableField); |
590 | if (d->joinMode == QSqlRelationalTableModel::InnerJoin) { |
591 | // FIXME: InnerJoin code is known to be broken. |
592 | // Use LeftJoin mode if you want correct behavior. |
593 | from = SqlrTm::comma(a: from, b: tblexpr); |
594 | conditions = SqlrTm::et(a: conditions, b: cond); |
595 | } else { |
596 | from = SqlrTm::concat(a: from, b: SqlrTm::leftJoin(s: tblexpr)); |
597 | from = SqlrTm::concat(a: from, b: SqlrTm::on(s: cond)); |
598 | } |
599 | } else { |
600 | fList = SqlrTm::comma(a: fList, b: tableField); |
601 | } |
602 | } |
603 | |
604 | if (fList.isEmpty()) |
605 | return QString(); |
606 | |
607 | const QString stmt = SqlrTm::concat(a: SqlrTm::select(s: fList), b: from); |
608 | const QString where = SqlrTm::where(s: SqlrTm::et(a: SqlrTm::paren(s: conditions), b: SqlrTm::paren(s: filter()))); |
609 | return SqlrTm::concat(a: SqlrTm::concat(a: stmt, b: where), b: orderByClause()); |
610 | } |
611 | |
612 | /*! |
613 | Returns a QSqlTableModel object for accessing the table for which |
614 | \a column is a foreign key, or \nullptr if there is no relation for |
615 | the given \a column. |
616 | |
617 | The returned object is owned by the QSqlRelationalTableModel. |
618 | |
619 | \sa setRelation(), relation() |
620 | */ |
621 | QSqlTableModel *QSqlRelationalTableModel::relationModel(int column) const |
622 | { |
623 | Q_D(const QSqlRelationalTableModel); |
624 | if (column < 0 || column >= d->relations.size()) |
625 | return nullptr; |
626 | |
627 | auto relation = d->relations.at(i: column); |
628 | if (!relation || !relation->isValid()) |
629 | return nullptr; |
630 | |
631 | if (!relation->model) |
632 | relation->populateModel(); |
633 | return relation->model; |
634 | } |
635 | |
636 | /*! |
637 | \reimp |
638 | */ |
639 | void QSqlRelationalTableModel::revertRow(int row) |
640 | { |
641 | QSqlTableModel::revertRow(row); |
642 | } |
643 | |
644 | /*! |
645 | \reimp |
646 | */ |
647 | void QSqlRelationalTableModel::clear() |
648 | { |
649 | Q_D(QSqlRelationalTableModel); |
650 | beginResetModel(); |
651 | d->clearChanges(); |
652 | d->relations.clear(); |
653 | QSqlTableModel::clear(); |
654 | endResetModel(); |
655 | } |
656 | |
657 | |
658 | /*! \enum QSqlRelationalTableModel::JoinMode |
659 | |
660 | \value InnerJoin - Inner join mode, return rows when there is at least one match in both tables. |
661 | \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). |
662 | |
663 | \sa QSqlRelationalTableModel::setJoinMode() |
664 | */ |
665 | |
666 | /*! |
667 | Sets the SQL \a joinMode to show or hide rows with NULL foreign keys. |
668 | In InnerJoin mode (the default) these rows will not be shown: use the |
669 | LeftJoin mode if you want to show them. |
670 | |
671 | \sa QSqlRelationalTableModel::JoinMode |
672 | */ |
673 | void QSqlRelationalTableModel::setJoinMode( QSqlRelationalTableModel::JoinMode joinMode ) |
674 | { |
675 | Q_D(QSqlRelationalTableModel); |
676 | d->joinMode = joinMode; |
677 | } |
678 | /*! |
679 | \reimp |
680 | */ |
681 | bool QSqlRelationalTableModel::select() |
682 | { |
683 | return QSqlTableModel::select(); |
684 | } |
685 | |
686 | /*! |
687 | \reimp |
688 | */ |
689 | void QSqlRelationalTableModel::setTable(const QString &table) |
690 | { |
691 | Q_D(QSqlRelationalTableModel); |
692 | |
693 | // memorize the table before applying the relations |
694 | d->baseRec = d->db.record(tablename: table); |
695 | |
696 | QSqlTableModel::setTable(table); |
697 | } |
698 | |
699 | /*! \internal |
700 | */ |
701 | void QSqlRelationalTableModelPrivate::translateFieldNames(QSqlRecord &values) const |
702 | { |
703 | for (int i = 0; i < values.count(); ++i) { |
704 | if (relations.value(i) && relations.at(i)->isValid()) { |
705 | QVariant v = values.value(i); |
706 | bool gen = values.isGenerated(i); |
707 | values.replace(pos: i, field: baseRec.field(i)); |
708 | values.setValue(i, val: v); |
709 | values.setGenerated(i, generated: gen); |
710 | } |
711 | } |
712 | } |
713 | |
714 | /*! |
715 | \reimp |
716 | */ |
717 | bool QSqlRelationalTableModel::updateRowInTable(int row, const QSqlRecord &values) |
718 | { |
719 | Q_D(QSqlRelationalTableModel); |
720 | |
721 | QSqlRecord rec = values; |
722 | d->translateFieldNames(values&: rec); |
723 | |
724 | return QSqlTableModel::updateRowInTable(row, values: rec); |
725 | } |
726 | |
727 | /*! |
728 | \reimp |
729 | */ |
730 | bool QSqlRelationalTableModel::insertRowIntoTable(const QSqlRecord &values) |
731 | { |
732 | Q_D(QSqlRelationalTableModel); |
733 | |
734 | QSqlRecord rec = values; |
735 | d->translateFieldNames(values&: rec); |
736 | |
737 | return QSqlTableModel::insertRowIntoTable(values: rec); |
738 | } |
739 | |
740 | /*! |
741 | \reimp |
742 | */ |
743 | QString QSqlRelationalTableModel::orderByClause() const |
744 | { |
745 | Q_D(const QSqlRelationalTableModel); |
746 | |
747 | const QSqlRelation rel = d->relations.value(i: d->sortColumn) ? d->relations.at(i: d->sortColumn)->rel : QSqlRelation(); |
748 | if (!rel.isValid()) |
749 | return QSqlTableModel::orderByClause(); |
750 | |
751 | QString f = d->fullyQualifiedFieldName(tableName: SqlrTm::relTablePrefix(i: d->sortColumn), fieldName: rel.displayColumn()); |
752 | f = d->sortOrder == Qt::AscendingOrder ? SqlrTm::asc(s: f) : SqlrTm::desc(s: f); |
753 | return SqlrTm::orderBy(s: f); |
754 | } |
755 | |
756 | /*! |
757 | \reimp |
758 | */ |
759 | bool QSqlRelationalTableModel::removeColumns(int column, int count, const QModelIndex &parent) |
760 | { |
761 | Q_D(QSqlRelationalTableModel); |
762 | |
763 | if (parent.isValid() || column < 0 || column + count > d->rec.count()) |
764 | return false; |
765 | |
766 | for (int i = 0; i < count; ++i) { |
767 | d->baseRec.remove(pos: column); |
768 | if (d->relations.size() > column) |
769 | d->relations.remove(i: column); |
770 | } |
771 | return QSqlTableModel::removeColumns(column, count, parent); |
772 | } |
773 | |
774 | QT_END_NAMESPACE |
775 | |
776 | #include "moc_qsqlrelationaltablemodel.cpp" |
777 | |