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 "qsqlresult.h" |
5 | |
6 | #include "qlist.h" |
7 | #include "qsqldriver.h" |
8 | #include "qsqlerror.h" |
9 | #include "qsqlfield.h" |
10 | #include "qsqlrecord.h" |
11 | #include "qsqlresult_p.h" |
12 | #include "quuid.h" |
13 | #include "qvariant.h" |
14 | #include "qdatetime.h" |
15 | #include "private/qsqldriver_p.h" |
16 | |
17 | QT_BEGIN_NAMESPACE |
18 | |
19 | using namespace Qt::StringLiterals; |
20 | |
21 | QString QSqlResultPrivate::holderAt(int index) const |
22 | { |
23 | return holders.size() > index ? holders.at(i: index).holderName : fieldSerial(index); |
24 | } |
25 | |
26 | QString QSqlResultPrivate::fieldSerial(qsizetype i) const |
27 | { |
28 | return QString(":%1"_L1).arg(a: i); |
29 | } |
30 | |
31 | static bool qIsAlnum(QChar ch) |
32 | { |
33 | uint u = uint(ch.unicode()); |
34 | // matches [a-zA-Z0-9_] |
35 | return u - 'a' < 26 || u - 'A' < 26 || u - '0' < 10 || u == '_'; |
36 | } |
37 | |
38 | QString QSqlResultPrivate::positionalToNamedBinding(const QString &query) const |
39 | { |
40 | if (!positionalBindingEnabled) |
41 | return query; |
42 | |
43 | const qsizetype n = query.size(); |
44 | |
45 | QString result; |
46 | result.reserve(asize: n * 5 / 4); |
47 | QChar closingQuote; |
48 | qsizetype count = 0; |
49 | bool ignoreBraces = (sqldriver->dbmsType() == QSqlDriver::PostgreSQL); |
50 | |
51 | for (qsizetype i = 0; i < n; ++i) { |
52 | QChar ch = query.at(i); |
53 | if (!closingQuote.isNull()) { |
54 | if (ch == closingQuote) { |
55 | if (closingQuote == u']' |
56 | && i + 1 < n && query.at(i: i + 1) == closingQuote) { |
57 | // consume the extra character. don't close. |
58 | ++i; |
59 | result += ch; |
60 | } else { |
61 | closingQuote = QChar(); |
62 | } |
63 | } |
64 | result += ch; |
65 | } else { |
66 | if (ch == u'?') { |
67 | result += fieldSerial(i: count++); |
68 | } else { |
69 | if (ch == u'\'' || ch == u'"' || ch == u'`') |
70 | closingQuote = ch; |
71 | else if (!ignoreBraces && ch == u'[') |
72 | closingQuote = u']'; |
73 | result += ch; |
74 | } |
75 | } |
76 | } |
77 | result.squeeze(); |
78 | return result; |
79 | } |
80 | |
81 | QString QSqlResultPrivate::namedToPositionalBinding(const QString &query) |
82 | { |
83 | // In the Interbase case if it is an EXECUTE BLOCK then it is up to the |
84 | // caller to make sure that it is not using named bindings for the wrong |
85 | // parts of the query since Interbase uses them literally |
86 | if (sqldriver->dbmsType() == QSqlDriver::Interbase && |
87 | query.trimmed().startsWith(s: "EXECUTE BLOCK"_L1, cs: Qt::CaseInsensitive)) |
88 | return query; |
89 | |
90 | const qsizetype n = query.size(); |
91 | |
92 | QString result; |
93 | result.reserve(asize: n); |
94 | QChar closingQuote; |
95 | int count = 0; |
96 | qsizetype i = 0; |
97 | bool ignoreBraces = (sqldriver->dbmsType() == QSqlDriver::PostgreSQL); |
98 | const bool qmarkNotationSupported = (sqldriver->dbmsType() != QSqlDriver::PostgreSQL); |
99 | |
100 | while (i < n) { |
101 | QChar ch = query.at(i); |
102 | if (!closingQuote.isNull()) { |
103 | if (ch == closingQuote) { |
104 | if (closingQuote == u']' |
105 | && i + 1 < n && query.at(i: i + 1) == closingQuote) { |
106 | // consume the extra character. don't close. |
107 | ++i; |
108 | result += ch; |
109 | } else { |
110 | closingQuote = QChar(); |
111 | } |
112 | } |
113 | result += ch; |
114 | ++i; |
115 | } else { |
116 | if (ch == u':' |
117 | && (i == 0 || query.at(i: i - 1) != u':') |
118 | && (i + 1 < n && qIsAlnum(ch: query.at(i: i + 1)))) { |
119 | int pos = i + 2; |
120 | while (pos < n && qIsAlnum(ch: query.at(i: pos))) |
121 | ++pos; |
122 | // if question mark notation is not supported we have to use |
123 | // the native binding. fieldSerial() should be renamed |
124 | // to toNativeBinding() and used unconditionally here |
125 | if (qmarkNotationSupported) |
126 | result += u'?'; |
127 | else |
128 | result += fieldSerial(i: count); |
129 | QString holder(query.mid(position: i, n: pos - i)); |
130 | indexes[holder].append(t: count++); |
131 | holders.append(t: QHolder(holder, i)); |
132 | i = pos; |
133 | } else { |
134 | if (ch == u'\'' || ch == u'"' || ch == u'`') |
135 | closingQuote = ch; |
136 | else if (!ignoreBraces && ch == u'[') |
137 | closingQuote = u']'; |
138 | result += ch; |
139 | ++i; |
140 | } |
141 | } |
142 | } |
143 | result.squeeze(); |
144 | values.resize(size: holders.size()); |
145 | return result; |
146 | } |
147 | |
148 | /*! |
149 | \class QSqlResult |
150 | \brief The QSqlResult class provides an abstract interface for |
151 | accessing data from specific SQL databases. |
152 | |
153 | \ingroup database |
154 | \inmodule QtSql |
155 | |
156 | Normally, you would use QSqlQuery instead of QSqlResult, since |
157 | QSqlQuery provides a generic wrapper for database-specific |
158 | implementations of QSqlResult. |
159 | |
160 | If you are implementing your own SQL driver (by subclassing |
161 | QSqlDriver), you will need to provide your own QSqlResult |
162 | subclass that implements all the pure virtual functions and other |
163 | virtual functions that you need. |
164 | |
165 | \sa QSqlDriver |
166 | */ |
167 | |
168 | /*! |
169 | \enum QSqlResult::BindingSyntax |
170 | |
171 | This enum type specifies the different syntaxes for specifying |
172 | placeholders in prepared queries. |
173 | |
174 | \value PositionalBinding Use the ODBC-style positional syntax, with "?" as placeholders. |
175 | \value NamedBinding Use the Oracle-style syntax with named placeholders (e.g., ":id") |
176 | |
177 | \sa bindingSyntax() |
178 | */ |
179 | |
180 | /*! |
181 | \enum QSqlResult::VirtualHookOperation |
182 | \internal |
183 | */ |
184 | |
185 | /*! |
186 | Creates a QSqlResult using database driver \a db. The object is |
187 | initialized to an inactive state. |
188 | |
189 | \sa isActive(), driver() |
190 | */ |
191 | |
192 | QSqlResult::QSqlResult(const QSqlDriver *db) |
193 | { |
194 | d_ptr = new QSqlResultPrivate(this, db); |
195 | Q_D(QSqlResult); |
196 | if (d->sqldriver) |
197 | setNumericalPrecisionPolicy(d->sqldriver->numericalPrecisionPolicy()); |
198 | } |
199 | |
200 | /*! \internal |
201 | */ |
202 | QSqlResult::QSqlResult(QSqlResultPrivate &dd) |
203 | : d_ptr(&dd) |
204 | { |
205 | Q_D(QSqlResult); |
206 | if (d->sqldriver) |
207 | setNumericalPrecisionPolicy(d->sqldriver->numericalPrecisionPolicy()); |
208 | } |
209 | |
210 | /*! |
211 | Destroys the object and frees any allocated resources. |
212 | */ |
213 | |
214 | QSqlResult::~QSqlResult() |
215 | { |
216 | Q_D(QSqlResult); |
217 | delete d; |
218 | } |
219 | |
220 | /*! |
221 | Sets the current query for the result to \a query. You must call |
222 | reset() to execute the query on the database. |
223 | |
224 | \sa reset(), lastQuery() |
225 | */ |
226 | |
227 | void QSqlResult::setQuery(const QString& query) |
228 | { |
229 | Q_D(QSqlResult); |
230 | d->sql = query; |
231 | } |
232 | |
233 | /*! |
234 | Returns the current SQL query text, or an empty string if there |
235 | isn't one. |
236 | |
237 | \sa setQuery() |
238 | */ |
239 | |
240 | QString QSqlResult::lastQuery() const |
241 | { |
242 | Q_D(const QSqlResult); |
243 | return d->sql; |
244 | } |
245 | |
246 | /*! |
247 | Returns the current (zero-based) row position of the result. May |
248 | return the special values QSql::BeforeFirstRow or |
249 | QSql::AfterLastRow. |
250 | |
251 | \sa setAt(), isValid() |
252 | */ |
253 | int QSqlResult::at() const |
254 | { |
255 | Q_D(const QSqlResult); |
256 | return d->idx; |
257 | } |
258 | |
259 | |
260 | /*! |
261 | Returns \c true if the result is positioned on a valid record (that |
262 | is, the result is not positioned before the first or after the |
263 | last record); otherwise returns \c false. |
264 | |
265 | \sa at() |
266 | */ |
267 | |
268 | bool QSqlResult::isValid() const |
269 | { |
270 | Q_D(const QSqlResult); |
271 | return d->idx != QSql::BeforeFirstRow && d->idx != QSql::AfterLastRow; |
272 | } |
273 | |
274 | /*! |
275 | \fn bool QSqlResult::isNull(int index) |
276 | |
277 | Returns \c true if the field at position \a index in the current row |
278 | is null; otherwise returns \c false. |
279 | */ |
280 | |
281 | /*! |
282 | Returns \c true if the result has records to be retrieved; otherwise |
283 | returns \c false. |
284 | */ |
285 | |
286 | bool QSqlResult::isActive() const |
287 | { |
288 | Q_D(const QSqlResult); |
289 | return d->active; |
290 | } |
291 | |
292 | /*! |
293 | This function is provided for derived classes to set the |
294 | internal (zero-based) row position to \a index. |
295 | |
296 | \sa at() |
297 | */ |
298 | |
299 | void QSqlResult::setAt(int index) |
300 | { |
301 | Q_D(QSqlResult); |
302 | d->idx = index; |
303 | } |
304 | |
305 | |
306 | /*! |
307 | This function is provided for derived classes to indicate whether |
308 | or not the current statement is a SQL \c SELECT statement. The \a |
309 | select parameter should be true if the statement is a \c SELECT |
310 | statement; otherwise it should be false. |
311 | |
312 | \sa isSelect() |
313 | */ |
314 | |
315 | void QSqlResult::setSelect(bool select) |
316 | { |
317 | Q_D(QSqlResult); |
318 | d->isSel = select; |
319 | } |
320 | |
321 | /*! |
322 | Returns \c true if the current result is from a \c SELECT statement; |
323 | otherwise returns \c false. |
324 | |
325 | \sa setSelect() |
326 | */ |
327 | |
328 | bool QSqlResult::isSelect() const |
329 | { |
330 | Q_D(const QSqlResult); |
331 | return d->isSel; |
332 | } |
333 | |
334 | /*! |
335 | Returns the driver associated with the result. This is the object |
336 | that was passed to the constructor. |
337 | */ |
338 | |
339 | const QSqlDriver *QSqlResult::driver() const |
340 | { |
341 | Q_D(const QSqlResult); |
342 | return d->sqldriver; |
343 | } |
344 | |
345 | |
346 | /*! |
347 | This function is provided for derived classes to set the internal |
348 | active state to \a active. |
349 | |
350 | \sa isActive() |
351 | */ |
352 | |
353 | void QSqlResult::setActive(bool active) |
354 | { |
355 | Q_D(QSqlResult); |
356 | if (active) |
357 | d->executedQuery = d->sql; |
358 | |
359 | d->active = active; |
360 | } |
361 | |
362 | /*! |
363 | This function is provided for derived classes to set the last |
364 | error to \a error. |
365 | |
366 | \sa lastError() |
367 | */ |
368 | |
369 | void QSqlResult::setLastError(const QSqlError &error) |
370 | { |
371 | Q_D(QSqlResult); |
372 | d->error = error; |
373 | } |
374 | |
375 | |
376 | /*! |
377 | Returns the last error associated with the result. |
378 | */ |
379 | |
380 | QSqlError QSqlResult::lastError() const |
381 | { |
382 | Q_D(const QSqlResult); |
383 | return d->error; |
384 | } |
385 | |
386 | /*! |
387 | \fn int QSqlResult::size() |
388 | |
389 | Returns the size of the \c SELECT result, or -1 if it cannot be |
390 | determined or if the query is not a \c SELECT statement. |
391 | |
392 | \sa numRowsAffected() |
393 | */ |
394 | |
395 | /*! |
396 | \fn int QSqlResult::numRowsAffected() |
397 | |
398 | Returns the number of rows affected by the last query executed, or |
399 | -1 if it cannot be determined or if the query is a \c SELECT |
400 | statement. |
401 | |
402 | \sa size() |
403 | */ |
404 | |
405 | /*! |
406 | \fn QVariant QSqlResult::data(int index) |
407 | |
408 | Returns the data for field \a index in the current row as |
409 | a QVariant. This function is only called if the result is in |
410 | an active state and is positioned on a valid record and \a index is |
411 | non-negative. Derived classes must reimplement this function and |
412 | return the value of field \a index, or QVariant() if it cannot be |
413 | determined. |
414 | */ |
415 | |
416 | /*! |
417 | \fn bool QSqlResult::reset(const QString &query) |
418 | |
419 | Sets the result to use the SQL statement \a query for subsequent |
420 | data retrieval. |
421 | |
422 | Derived classes must reimplement this function and apply the \a |
423 | query to the database. This function is only called after the |
424 | result is set to an inactive state and is positioned before the |
425 | first record of the new result. Derived classes should return |
426 | true if the query was successful and ready to be used, or false |
427 | otherwise. |
428 | |
429 | \sa setQuery() |
430 | */ |
431 | |
432 | /*! |
433 | \fn bool QSqlResult::fetch(int index) |
434 | |
435 | Positions the result to an arbitrary (zero-based) row \a index. |
436 | |
437 | This function is only called if the result is in an active state. |
438 | Derived classes must reimplement this function and position the |
439 | result to the row \a index, and call setAt() with an appropriate |
440 | value. Return true to indicate success, or false to signify |
441 | failure. |
442 | |
443 | \sa isActive(), fetchFirst(), fetchLast(), fetchNext(), fetchPrevious() |
444 | */ |
445 | |
446 | /*! |
447 | \fn bool QSqlResult::fetchFirst() |
448 | |
449 | Positions the result to the first record (row 0) in the result. |
450 | |
451 | This function is only called if the result is in an active state. |
452 | Derived classes must reimplement this function and position the |
453 | result to the first record, and call setAt() with an appropriate |
454 | value. Return true to indicate success, or false to signify |
455 | failure. |
456 | |
457 | \sa fetch(), fetchLast() |
458 | */ |
459 | |
460 | /*! |
461 | \fn bool QSqlResult::fetchLast() |
462 | |
463 | Positions the result to the last record (last row) in the result. |
464 | |
465 | This function is only called if the result is in an active state. |
466 | Derived classes must reimplement this function and position the |
467 | result to the last record, and call setAt() with an appropriate |
468 | value. Return true to indicate success, or false to signify |
469 | failure. |
470 | |
471 | \sa fetch(), fetchFirst() |
472 | */ |
473 | |
474 | /*! |
475 | Positions the result to the next available record (row) in the |
476 | result. |
477 | |
478 | This function is only called if the result is in an active |
479 | state. The default implementation calls fetch() with the next |
480 | index. Derived classes can reimplement this function and position |
481 | the result to the next record in some other way, and call setAt() |
482 | with an appropriate value. Return true to indicate success, or |
483 | false to signify failure. |
484 | |
485 | \sa fetch(), fetchPrevious() |
486 | */ |
487 | |
488 | bool QSqlResult::fetchNext() |
489 | { |
490 | return fetch(i: at() + 1); |
491 | } |
492 | |
493 | /*! |
494 | Positions the result to the previous record (row) in the result. |
495 | |
496 | This function is only called if the result is in an active state. |
497 | The default implementation calls fetch() with the previous index. |
498 | Derived classes can reimplement this function and position the |
499 | result to the next record in some other way, and call setAt() |
500 | with an appropriate value. Return true to indicate success, or |
501 | false to signify failure. |
502 | */ |
503 | |
504 | bool QSqlResult::fetchPrevious() |
505 | { |
506 | return fetch(i: at() - 1); |
507 | } |
508 | |
509 | /*! |
510 | Returns \c true if you can only scroll forward through the result |
511 | set; otherwise returns \c false. |
512 | |
513 | \sa setForwardOnly() |
514 | */ |
515 | bool QSqlResult::isForwardOnly() const |
516 | { |
517 | Q_D(const QSqlResult); |
518 | return d->forwardOnly; |
519 | } |
520 | |
521 | /*! |
522 | Sets forward only mode to \a forward. If \a forward is true, only |
523 | fetchNext() is allowed for navigating the results. Forward only |
524 | mode needs much less memory since results do not have to be |
525 | cached. By default, this feature is disabled. |
526 | |
527 | Setting forward only to false is a suggestion to the database engine, |
528 | which has the final say on whether a result set is forward only or |
529 | scrollable. isForwardOnly() will always return the correct status of |
530 | the result set. |
531 | |
532 | \note Calling setForwardOnly after execution of the query will result |
533 | in unexpected results at best, and crashes at worst. |
534 | |
535 | \note To make sure the forward-only query completed successfully, |
536 | the application should check lastError() for an error not only after |
537 | executing the query, but also after navigating the query results. |
538 | |
539 | \warning PostgreSQL: While navigating the query results in forward-only |
540 | mode, do not execute any other SQL command on the same database |
541 | connection. This will cause the query results to be lost. |
542 | |
543 | \sa isForwardOnly(), fetchNext(), QSqlQuery::setForwardOnly() |
544 | */ |
545 | void QSqlResult::setForwardOnly(bool forward) |
546 | { |
547 | Q_D(QSqlResult); |
548 | d->forwardOnly = forward; |
549 | } |
550 | |
551 | /*! |
552 | Prepares the given \a query, using the underlying database |
553 | functionality where possible. Returns \c true if the query is |
554 | prepared successfully; otherwise returns \c false. |
555 | |
556 | Note: This method should have been called "safePrepare()". |
557 | |
558 | \sa prepare() |
559 | */ |
560 | bool QSqlResult::savePrepare(const QString& query) |
561 | { |
562 | Q_D(QSqlResult); |
563 | if (!driver()) |
564 | return false; |
565 | d->clear(); |
566 | d->sql = query; |
567 | if (!driver()->hasFeature(f: QSqlDriver::PreparedQueries)) |
568 | return prepare(query); |
569 | |
570 | // parse the query to memorize parameter location |
571 | d->executedQuery = d->namedToPositionalBinding(query); |
572 | |
573 | if (driver()->hasFeature(f: QSqlDriver::NamedPlaceholders)) |
574 | d->executedQuery = d->positionalToNamedBinding(query); |
575 | |
576 | return prepare(query: d->executedQuery); |
577 | } |
578 | |
579 | /*! |
580 | Prepares the given \a query for execution; the query will normally |
581 | use placeholders so that it can be executed repeatedly. Returns |
582 | true if the query is prepared successfully; otherwise returns \c false. |
583 | |
584 | \sa exec() |
585 | */ |
586 | bool QSqlResult::prepare(const QString& query) |
587 | { |
588 | Q_D(QSqlResult); |
589 | d->sql = query; |
590 | if (d->holders.isEmpty()) { |
591 | // parse the query to memorize parameter location |
592 | d->namedToPositionalBinding(query); |
593 | } |
594 | return true; // fake prepares should always succeed |
595 | } |
596 | |
597 | bool QSqlResultPrivate::isVariantNull(const QVariant &variant) |
598 | { |
599 | if (variant.isNull()) |
600 | return true; |
601 | |
602 | switch (variant.typeId()) { |
603 | case qMetaTypeId<QString>(): |
604 | return static_cast<const QString*>(variant.constData())->isNull(); |
605 | case qMetaTypeId<QByteArray>(): |
606 | return static_cast<const QByteArray*>(variant.constData())->isNull(); |
607 | case qMetaTypeId<QDateTime>(): |
608 | // We treat invalid date-time as null, since its ISODate would be empty. |
609 | return !static_cast<const QDateTime*>(variant.constData())->isValid(); |
610 | case qMetaTypeId<QDate>(): |
611 | return static_cast<const QDate*>(variant.constData())->isNull(); |
612 | case qMetaTypeId<QTime>(): |
613 | // As for QDateTime, QTime can be invalid without being null. |
614 | return !static_cast<const QTime*>(variant.constData())->isValid(); |
615 | case qMetaTypeId<QUuid>(): |
616 | return static_cast<const QUuid*>(variant.constData())->isNull(); |
617 | default: |
618 | break; |
619 | } |
620 | |
621 | return false; |
622 | } |
623 | |
624 | /*! |
625 | Executes the query, returning true if successful; otherwise returns |
626 | false. |
627 | |
628 | \sa prepare() |
629 | */ |
630 | bool QSqlResult::exec() |
631 | { |
632 | Q_D(QSqlResult); |
633 | bool ret; |
634 | // fake preparation - just replace the placeholders.. |
635 | QString query = lastQuery(); |
636 | if (d->binds == NamedBinding) { |
637 | for (qsizetype i = d->holders.size() - 1; i >= 0; --i) { |
638 | const QString &holder = d->holders.at(i).holderName; |
639 | const QVariant val = d->values.value(i: d->indexes.value(key: holder).value(i: 0,defaultValue: -1)); |
640 | QSqlField f(""_L1, val.metaType()); |
641 | if (QSqlResultPrivate::isVariantNull(variant: val)) |
642 | f.setValue(QVariant()); |
643 | else |
644 | f.setValue(val); |
645 | query = query.replace(i: d->holders.at(i).holderPos, |
646 | len: holder.size(), after: driver()->formatValue(field: f)); |
647 | } |
648 | } else { |
649 | qsizetype i = 0; |
650 | for (const QVariant &var : std::as_const(t&: d->values)) { |
651 | i = query.indexOf(ch: u'?', from: i); |
652 | if (i == -1) |
653 | continue; |
654 | QSqlField f(""_L1, var.metaType()); |
655 | if (QSqlResultPrivate::isVariantNull(variant: var)) |
656 | f.clear(); |
657 | else |
658 | f.setValue(var); |
659 | const QString val = driver()->formatValue(field: f); |
660 | query = query.replace(i, len: 1, after: val); |
661 | i += val.size(); |
662 | } |
663 | } |
664 | |
665 | // have to retain the original query with placeholders |
666 | QString orig = lastQuery(); |
667 | ret = reset(sqlquery: query); |
668 | d->executedQuery = query; |
669 | setQuery(orig); |
670 | d->resetBindCount(); |
671 | return ret; |
672 | } |
673 | |
674 | /*! |
675 | Binds the value \a val of parameter type \a paramType to position \a index |
676 | in the current record (row). |
677 | |
678 | \sa addBindValue() |
679 | */ |
680 | void QSqlResult::bindValue(int index, const QVariant& val, QSql::ParamType paramType) |
681 | { |
682 | Q_D(QSqlResult); |
683 | d->binds = PositionalBinding; |
684 | QList<int> &indexes = d->indexes[d->fieldSerial(i: index)]; |
685 | if (!indexes.contains(t: index)) |
686 | indexes.append(t: index); |
687 | if (d->values.size() <= index) |
688 | d->values.resize(size: index + 1); |
689 | d->values[index] = val; |
690 | if (paramType != QSql::In || !d->types.isEmpty()) |
691 | d->types[index] = paramType; |
692 | } |
693 | |
694 | /*! |
695 | \overload |
696 | |
697 | Binds the value \a val of parameter type \a paramType to the \a |
698 | placeholder name in the current record (row). |
699 | |
700 | \note Binding an undefined placeholder will result in undefined behavior. |
701 | |
702 | \sa QSqlQuery::bindValue() |
703 | */ |
704 | void QSqlResult::bindValue(const QString& placeholder, const QVariant& val, |
705 | QSql::ParamType paramType) |
706 | { |
707 | Q_D(QSqlResult); |
708 | d->binds = NamedBinding; |
709 | // if the index has already been set when doing emulated named |
710 | // bindings - don't reset it |
711 | const QList<int> indexes = d->indexes.value(key: placeholder); |
712 | for (int idx : indexes) { |
713 | if (d->values.size() <= idx) |
714 | d->values.resize(size: idx + 1); |
715 | d->values[idx] = val; |
716 | if (paramType != QSql::In || !d->types.isEmpty()) |
717 | d->types[idx] = paramType; |
718 | } |
719 | } |
720 | |
721 | /*! |
722 | Binds the value \a val of parameter type \a paramType to the next |
723 | available position in the current record (row). |
724 | |
725 | \sa bindValue() |
726 | */ |
727 | void QSqlResult::addBindValue(const QVariant& val, QSql::ParamType paramType) |
728 | { |
729 | Q_D(QSqlResult); |
730 | d->binds = PositionalBinding; |
731 | bindValue(index: d->bindCount, val, paramType); |
732 | ++d->bindCount; |
733 | } |
734 | |
735 | /*! |
736 | Returns the value bound at position \a index in the current record |
737 | (row). |
738 | |
739 | \sa bindValue(), boundValues() |
740 | */ |
741 | QVariant QSqlResult::boundValue(int index) const |
742 | { |
743 | Q_D(const QSqlResult); |
744 | return d->values.value(i: index); |
745 | } |
746 | |
747 | /*! |
748 | \overload |
749 | |
750 | Returns the value bound by the given \a placeholder name in the |
751 | current record (row). |
752 | |
753 | \sa bindValueType() |
754 | */ |
755 | QVariant QSqlResult::boundValue(const QString& placeholder) const |
756 | { |
757 | Q_D(const QSqlResult); |
758 | const QList<int> indexes = d->indexes.value(key: placeholder); |
759 | return d->values.value(i: indexes.value(i: 0,defaultValue: -1)); |
760 | } |
761 | |
762 | /*! |
763 | Returns the parameter type for the value bound at position \a index. |
764 | |
765 | \sa boundValue() |
766 | */ |
767 | QSql::ParamType QSqlResult::bindValueType(int index) const |
768 | { |
769 | Q_D(const QSqlResult); |
770 | return d->types.value(key: index, defaultValue: QSql::In); |
771 | } |
772 | |
773 | /*! |
774 | \overload |
775 | |
776 | Returns the parameter type for the value bound with the given \a |
777 | placeholder name. |
778 | */ |
779 | QSql::ParamType QSqlResult::bindValueType(const QString& placeholder) const |
780 | { |
781 | Q_D(const QSqlResult); |
782 | return d->types.value(key: d->indexes.value(key: placeholder).value(i: 0,defaultValue: -1), defaultValue: QSql::In); |
783 | } |
784 | |
785 | /*! |
786 | Returns the number of bound values in the result. |
787 | |
788 | \sa boundValues() |
789 | */ |
790 | int QSqlResult::boundValueCount() const |
791 | { |
792 | Q_D(const QSqlResult); |
793 | return d->values.size(); |
794 | } |
795 | |
796 | /*! |
797 | Returns a list of the result's bound values for the current |
798 | record (row). |
799 | |
800 | \sa boundValueCount() |
801 | */ |
802 | QVariantList QSqlResult::boundValues(QT6_IMPL_NEW_OVERLOAD) const |
803 | { |
804 | Q_D(const QSqlResult); |
805 | return d->values; |
806 | } |
807 | |
808 | /*! |
809 | \overload |
810 | |
811 | Returns a mutable reference to the list of the result's bound values |
812 | for the current record (row). |
813 | |
814 | \sa boundValueCount() |
815 | */ |
816 | QVariantList &QSqlResult::boundValues(QT6_IMPL_NEW_OVERLOAD) |
817 | { |
818 | Q_D(QSqlResult); |
819 | return d->values; |
820 | } |
821 | |
822 | |
823 | /*! |
824 | Returns the binding syntax used by prepared queries. |
825 | */ |
826 | QSqlResult::BindingSyntax QSqlResult::bindingSyntax() const |
827 | { |
828 | Q_D(const QSqlResult); |
829 | return d->binds; |
830 | } |
831 | |
832 | /*! |
833 | Clears the entire result set and releases any associated |
834 | resources. |
835 | */ |
836 | void QSqlResult::clear() |
837 | { |
838 | Q_D(QSqlResult); |
839 | d->clear(); |
840 | } |
841 | |
842 | /*! |
843 | Returns the query that was actually executed. This may differ from |
844 | the query that was passed, for example if bound values were used |
845 | with a prepared query and the underlying database doesn't support |
846 | prepared queries. |
847 | |
848 | \sa exec(), setQuery() |
849 | */ |
850 | QString QSqlResult::executedQuery() const |
851 | { |
852 | Q_D(const QSqlResult); |
853 | return d->executedQuery; |
854 | } |
855 | |
856 | /*! |
857 | Resets the number of bind parameters. |
858 | */ |
859 | void QSqlResult::resetBindCount() |
860 | { |
861 | Q_D(QSqlResult); |
862 | d->resetBindCount(); |
863 | } |
864 | |
865 | /*! |
866 | Returns the names of all bound values. |
867 | |
868 | \sa boundValue(), boundValueName() |
869 | */ |
870 | QStringList QSqlResult::boundValueNames() const |
871 | { |
872 | Q_D(const QSqlResult); |
873 | QList<QString> ret; |
874 | for (const QHolder &holder : std::as_const(t: d->holders)) |
875 | ret.push_back(t: holder.holderName); |
876 | return ret; |
877 | } |
878 | |
879 | /*! |
880 | Returns the name of the bound value at position \a index in the |
881 | current record (row). |
882 | |
883 | \sa boundValue(), boundValueNames() |
884 | */ |
885 | QString QSqlResult::boundValueName(int index) const |
886 | { |
887 | Q_D(const QSqlResult); |
888 | return d->holderAt(index); |
889 | } |
890 | |
891 | /*! |
892 | Returns \c true if at least one of the query's bound values is a \c |
893 | QSql::Out or a QSql::InOut; otherwise returns \c false. |
894 | |
895 | \sa bindValueType() |
896 | */ |
897 | bool QSqlResult::hasOutValues() const |
898 | { |
899 | Q_D(const QSqlResult); |
900 | if (d->types.isEmpty()) |
901 | return false; |
902 | QHash<int, QSql::ParamType>::ConstIterator it; |
903 | for (it = d->types.constBegin(); it != d->types.constEnd(); ++it) { |
904 | if (it.value() != QSql::In) |
905 | return true; |
906 | } |
907 | return false; |
908 | } |
909 | |
910 | /*! |
911 | Returns the current record if the query is active; otherwise |
912 | returns an empty QSqlRecord. |
913 | |
914 | The default implementation always returns an empty QSqlRecord. |
915 | |
916 | \sa isActive() |
917 | */ |
918 | QSqlRecord QSqlResult::record() const |
919 | { |
920 | return QSqlRecord(); |
921 | } |
922 | |
923 | /*! |
924 | Returns the object ID of the most recent inserted row if the |
925 | database supports it. |
926 | An invalid QVariant will be returned if the query did not |
927 | insert any value or if the database does not report the id back. |
928 | If more than one row was touched by the insert, the behavior is |
929 | undefined. |
930 | |
931 | Note that for Oracle databases the row's ROWID will be returned, |
932 | while for MySQL databases the row's auto-increment field will |
933 | be returned. |
934 | |
935 | \sa QSqlDriver::hasFeature() |
936 | */ |
937 | QVariant QSqlResult::lastInsertId() const |
938 | { |
939 | return QVariant(); |
940 | } |
941 | |
942 | /*! \internal |
943 | */ |
944 | void QSqlResult::virtual_hook(int, void *) |
945 | { |
946 | } |
947 | |
948 | /*! \internal |
949 | Executes a prepared query in batch mode if the driver supports it, |
950 | otherwise emulates a batch execution using bindValue() and exec(). |
951 | QSqlDriver::hasFeature() can be used to find out whether a driver |
952 | supports batch execution. |
953 | |
954 | Batch execution can be faster for large amounts of data since it |
955 | reduces network roundtrips. |
956 | |
957 | For batch executions, bound values have to be provided as lists |
958 | of variants (QVariantList). |
959 | |
960 | Each list must contain values of the same type. All lists must |
961 | contain equal amount of values (rows). |
962 | |
963 | NULL values are passed in as typed QVariants, for example |
964 | \c {QVariant(QMetaType::fromType<int>())} for an integer NULL value. |
965 | |
966 | Example: |
967 | |
968 | \snippet code/src_sql_kernel_qsqlresult.cpp 0 |
969 | |
970 | Here, we insert two rows into a SQL table, with each row containing three values. |
971 | |
972 | \sa exec(), QSqlDriver::hasFeature() |
973 | */ |
974 | bool QSqlResult::execBatch(bool arrayBind) |
975 | { |
976 | Q_UNUSED(arrayBind); |
977 | Q_D(QSqlResult); |
978 | |
979 | const QList<QVariant> values = d->values; |
980 | if (values.size() == 0) |
981 | return false; |
982 | const qsizetype batchCount = values.at(i: 0).toList().size(); |
983 | const qsizetype valueCount = values.size(); |
984 | for (qsizetype i = 0; i < batchCount; ++i) { |
985 | for (qsizetype j = 0; j < valueCount; ++j) |
986 | bindValue(index: j, val: values.at(i: j).toList().at(i), paramType: QSql::In); |
987 | if (!exec()) |
988 | return false; |
989 | } |
990 | return true; |
991 | } |
992 | |
993 | /*! \internal |
994 | */ |
995 | void QSqlResult::detachFromResultSet() |
996 | { |
997 | } |
998 | |
999 | /*! \internal |
1000 | */ |
1001 | void QSqlResult::setNumericalPrecisionPolicy(QSql::NumericalPrecisionPolicy policy) |
1002 | { |
1003 | Q_D(QSqlResult); |
1004 | d->precisionPolicy = policy; |
1005 | } |
1006 | |
1007 | /*! \internal |
1008 | */ |
1009 | QSql::NumericalPrecisionPolicy QSqlResult::numericalPrecisionPolicy() const |
1010 | { |
1011 | Q_D(const QSqlResult); |
1012 | return d->precisionPolicy; |
1013 | } |
1014 | |
1015 | /*! \internal |
1016 | */ |
1017 | void QSqlResult::setPositionalBindingEnabled(bool enable) |
1018 | { |
1019 | Q_D(QSqlResult); |
1020 | d->positionalBindingEnabled = enable; |
1021 | } |
1022 | |
1023 | /*! \internal |
1024 | */ |
1025 | bool QSqlResult::isPositionalBindingEnabled() const |
1026 | { |
1027 | Q_D(const QSqlResult); |
1028 | return d->positionalBindingEnabled; |
1029 | } |
1030 | |
1031 | |
1032 | /*! \internal |
1033 | */ |
1034 | bool QSqlResult::nextResult() |
1035 | { |
1036 | return false; |
1037 | } |
1038 | |
1039 | /*! |
1040 | Returns the low-level database handle for this result set |
1041 | wrapped in a QVariant or an invalid QVariant if there is no handle. |
1042 | |
1043 | \warning Use this with uttermost care and only if you know what you're doing. |
1044 | |
1045 | \warning The handle returned here can become a stale pointer if the result |
1046 | is modified (for example, if you clear it). |
1047 | |
1048 | \warning The handle can be NULL if the result was not executed yet. |
1049 | |
1050 | \warning PostgreSQL: in forward-only mode, the handle of QSqlResult can change |
1051 | after calling fetch(), fetchFirst(), fetchLast(), fetchNext(), fetchPrevious(), |
1052 | nextResult(). |
1053 | |
1054 | The handle returned here is database-dependent, you should query the type |
1055 | name of the variant before accessing it. |
1056 | |
1057 | This example retrieves the handle for a sqlite result: |
1058 | |
1059 | \snippet code/src_sql_kernel_qsqlresult.cpp 1 |
1060 | |
1061 | This snippet returns the handle for PostgreSQL or MySQL: |
1062 | |
1063 | \snippet code/src_sql_kernel_qsqlresult_snippet.cpp 2 |
1064 | |
1065 | \sa QSqlDriver::handle() |
1066 | */ |
1067 | QVariant QSqlResult::handle() const |
1068 | { |
1069 | return QVariant(); |
1070 | } |
1071 | |
1072 | QT_END_NAMESPACE |
1073 |
Definitions
- holderAt
- fieldSerial
- qIsAlnum
- positionalToNamedBinding
- namedToPositionalBinding
- QSqlResult
- QSqlResult
- ~QSqlResult
- setQuery
- lastQuery
- at
- isValid
- isActive
- setAt
- setSelect
- isSelect
- driver
- setActive
- setLastError
- lastError
- fetchNext
- fetchPrevious
- isForwardOnly
- setForwardOnly
- savePrepare
- prepare
- isVariantNull
- exec
- bindValue
- bindValue
- addBindValue
- boundValue
- boundValue
- bindValueType
- bindValueType
- boundValueCount
- boundValues
- boundValues
- bindingSyntax
- clear
- executedQuery
- resetBindCount
- boundValueNames
- boundValueName
- hasOutValues
- record
- lastInsertId
- virtual_hook
- execBatch
- detachFromResultSet
- setNumericalPrecisionPolicy
- numericalPrecisionPolicy
- setPositionalBindingEnabled
- isPositionalBindingEnabled
- nextResult
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