summaryrefslogtreecommitdiff
path: root/framework/Data/TDbConnection.php
blob: 3134bb491f75bf7561d83a2e13657a35c045dc9f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
<?php
/**
 * TDbConnection class file
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.pradosoft.com/
 * @copyright Copyright &copy; 2005-2014 PradoSoft
 * @license http://www.pradosoft.com/license/
 * @version $Id: TDbConnection.php 3245 2013-01-07 20:23:32Z ctrlaltca $
 * @package System.Data
 */

Prado::using('System.Data.TDbTransaction');
Prado::using('System.Data.TDbCommand');

/**
 * TDbConnection class
 *
 * TDbConnection represents a connection to a database.
 *
 * TDbConnection works together with {@link TDbCommand}, {@link TDbDataReader}
 * and {@link TDbTransaction} to provide data access to various DBMS
 * in a common set of APIs. They are a thin wrapper of the {@link http://www.php.net/manual/en/ref.pdo.php PDO}
 * PHP extension.
 *
 * To establish a connection, set {@link setActive Active} to true after
 * specifying {@link setConnectionString ConnectionString}, {@link setUsername Username}
 * and {@link setPassword Password}.
 *
 * Since 3.1.2, the connection charset can be set (for MySQL and PostgreSQL databases only)
 * using the {@link setCharset Charset} property. The value of this property is database dependant.
 * e.g. for mysql, you can use 'latin1' for cp1252 West European, 'utf8' for unicode, ...
 *
 * The following example shows how to create a TDbConnection instance and establish
 * the actual connection:
 * <code>
 * $connection=new TDbConnection($dsn,$username,$password);
 * $connection->Active=true;
 * </code>
 *
 * After the DB connection is established, one can execute an SQL statement like the following:
 * <code>
 * $command=$connection->createCommand($sqlStatement);
 * $command->execute();   // a non-query SQL statement execution
 * // or execute an SQL query and fetch the result set
 * $reader=$command->query();
 *
 * // each $row is an array representing a row of data
 * foreach($reader as $row) ...
 * </code>
 *
 * One can do prepared SQL execution and bind parameters to the prepared SQL:
 * <code>
 * $command=$connection->createCommand($sqlStatement);
 * $command->bindParameter($name1,$value1);
 * $command->bindParameter($name2,$value2);
 * $command->execute();
 * </code>
 *
 * To use transaction, do like the following:
 * <code>
 * $transaction=$connection->beginTransaction();
 * try
 * {
 *    $connection->createCommand($sql1)->execute();
 *    $connection->createCommand($sql2)->execute();
 *    //.... other SQL executions
 *    $transaction->commit();
 * }
 * catch(Exception $e)
 * {
 *    $transaction->rollBack();
 * }
 * </code>
 *
 * TDbConnection provides a set of methods to support setting and querying
 * of certain DBMS attributes, such as {@link getNullConversion NullConversion}.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @version $Id: TDbConnection.php 3245 2013-01-07 20:23:32Z ctrlaltca $
 * @package System.Data
 * @since 3.0
 */
class TDbConnection extends TComponent
{
	/**
	 *
	 * @since 3.1.7
	 */
	const DEFAULT_TRANSACTION_CLASS = 'System.Data.TDbTransaction';

	private $_dsn='';
	private $_username='';
	private $_password='';
	private $_charset='';
	private $_attributes=array();
	private $_active=false;
	private $_pdo=null;
	private $_transaction;

	/**
	 * @var TDbMetaData
	 */
	private $_dbMeta = null;

	/**
	 * @var string
	 * @since 3.1.7
	 */
	private $_transactionClass=self::DEFAULT_TRANSACTION_CLASS;

	/**
	 * Constructor.
	 * Note, the DB connection is not established when this connection
	 * instance is created. Set {@link setActive Active} property to true
	 * to establish the connection.
	 * Since 3.1.2, you can set the charset for MySql connection
	 *
	 * @param string The Data Source Name, or DSN, contains the information required to connect to the database.
	 * @param string The user name for the DSN string.
	 * @param string The password for the DSN string.
	 * @param string Charset used for DB Connection (MySql & pgsql only). If not set, will use the default charset of your database server
	 * @see http://www.php.net/manual/en/function.PDO-construct.php
	 */
	public function __construct($dsn='',$username='',$password='', $charset='')
	{
		$this->_dsn=$dsn;
		$this->_username=$username;
		$this->_password=$password;
		$this->_charset=$charset;
	}

	/**
	 * Close the connection when serializing.
	 */
	public function __sleep()
	{
//		$this->close(); - DO NOT CLOSE the current connection as serializing doesn't neccessarily mean we don't this connection anymore in the current session
		return array_diff(parent::__sleep(),array("\0TDbConnection\0_pdo","\0TDbConnection\0_active"));
	}

	/**
	 * @return array list of available PDO drivers
	 * @see http://www.php.net/manual/en/function.PDO-getAvailableDrivers.php
	 */
	public static function getAvailableDrivers()
	{
		return PDO::getAvailableDrivers();
	}

	/**
	 * @return boolean whether the DB connection is established
	 */
	public function getActive()
	{
		return $this->_active;
	}

	/**
	 * Open or close the DB connection.
	 * @param boolean whether to open or close DB connection
	 * @throws TDbException if connection fails
	 */
	public function setActive($value)
	{
		$value=TPropertyValue::ensureBoolean($value);
		if($value!==$this->_active)
		{
			if($value)
				$this->open();
			else
				$this->close();
		}
	}

	/**
	 * Opens DB connection if it is currently not
	 * @throws TDbException if connection fails
	 */
	protected function open()
	{
		if($this->_pdo===null)
		{
			try
			{
				$this->_pdo=new PDO($this->getConnectionString(),$this->getUsername(),
									$this->getPassword(),$this->_attributes);
				// This attribute is only useful for PDO::MySql driver.
				// Ignore the warning if a driver doesn't understand this.
				@$this->_pdo->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
				$this->_pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
				$this->_active=true;
				$this->setConnectionCharset();
			}
			catch(PDOException $e)
			{
				throw new TDbException('dbconnection_open_failed',$e->getMessage());
			}
		}
	}

	/**
	 * Closes the currently active DB connection.
	 * It does nothing if the connection is already closed.
	 */
	protected function close()
	{
		$this->_pdo=null;
		$this->_active=false;
	}

	/*
	 * Set the database connection charset.
	 * Only MySql databases are supported for now.
	 * @since 3.1.2
	 */
	protected function setConnectionCharset()
	{
		if ($this->_charset === '' || $this->_active === false)
			return;
		switch ($this->_pdo->getAttribute(PDO::ATTR_DRIVER_NAME))
		{
			case 'mysql':
			case 'sqlite':
				$stmt = $this->_pdo->prepare('SET NAMES ?');
			break;
			case 'pgsql':
				$stmt = $this->_pdo->prepare('SET client_encoding TO ?');
			break;
			default:
				throw new TDbException('dbconnection_unsupported_driver_charset', $driver);
		}
		$stmt->execute(array($this->_charset));
	}

	/**
	 * @return string The Data Source Name, or DSN, contains the information required to connect to the database.
	 */
	public function getConnectionString()
	{
		return $this->_dsn;
	}

	/**
	 * @param string The Data Source Name, or DSN, contains the information required to connect to the database.
	 * @see http://www.php.net/manual/en/function.PDO-construct.php
	 */
	public function setConnectionString($value)
	{
		$this->_dsn=$value;
	}

	/**
	 * @return string the username for establishing DB connection. Defaults to empty string.
	 */
	public function getUsername()
	{
		return $this->_username;
	}

	/**
	 * @param string the username for establishing DB connection
	 */
	public function setUsername($value)
	{
		$this->_username=$value;
	}

	/**
	 * @return string the password for establishing DB connection. Defaults to empty string.
	 */
	public function getPassword()
	{
		return $this->_password;
	}

	/**
	 * @param string the password for establishing DB connection
	 */
	public function setPassword($value)
	{
		$this->_password=$value;
	}

	/**
	 * @return string the charset used for database connection. Defaults to emtpy string.
	 */
	public function getCharset ()
	{
		return $this->_charset;
	}

	/**
	 * @param string the charset used for database connection
	 */
	public function setCharset ($value)
	{
		$this->_charset=$value;
		$this->setConnectionCharset();
	}

	/**
	 * @return PDO the PDO instance, null if the connection is not established yet
	 */
	public function getPdoInstance()
	{
		return $this->_pdo;
	}

	/**
	 * Creates a command for execution.
	 * @param string SQL statement associated with the new command.
	 * @return TDbCommand the DB command
	 * @throws TDbException if the connection is not active
	 */
	public function createCommand($sql)
	{
		if($this->getActive())
			return new TDbCommand($this,$sql);
		else
			throw new TDbException('dbconnection_connection_inactive');
	}

	/**
	 * @return TDbTransaction the currently active transaction. Null if no active transaction.
	 */
	public function getCurrentTransaction()
	{
		if($this->_transaction!==null)
		{
			if($this->_transaction->getActive())
				return $this->_transaction;
		}
		return null;
	}

	/**
	 * Starts a transaction.
	 * @return TDbTransaction the transaction initiated
	 * @throws TDbException if the connection is not active
	 */
	public function beginTransaction()
	{
		if($this->getActive())
		{
			$this->_pdo->beginTransaction();
			return $this->_transaction=Prado::createComponent($this->getTransactionClass(), $this);
		}
		else
			throw new TDbException('dbconnection_connection_inactive');
	}

	/**
	 * @return string Transaction class name to be created by calling {@link TDbConnection::beginTransaction}. Defaults to 'System.Data.TDbTransaction'.
	 * @since 3.1.7
	 */
	public function getTransactionClass()
	{
		return $this->_transactionClass;
	}


	/**
	 * @param string Transaction class name to be created by calling {@link TDbConnection::beginTransaction}.
	 * @since 3.1.7
	 */
	public function setTransactionClass($value)
	{
		$this->_transactionClass = (string)$value;
	}

	/**
	 * Returns the ID of the last inserted row or sequence value.
	 * @param string name of the sequence object (required by some DBMS)
	 * @return string the row ID of the last row inserted, or the last value retrieved from the sequence object
	 * @see http://www.php.net/manual/en/function.PDO-lastInsertId.php
	 */
	public function getLastInsertID($sequenceName='')
	{
		if($this->getActive())
			return $this->_pdo->lastInsertId($sequenceName);
		else
			throw new TDbException('dbconnection_connection_inactive');
	}

	/**
	 * Quotes a string for use in a query.
	 * @param string string to be quoted
	 * @return string the properly quoted string
	 * @see http://www.php.net/manual/en/function.PDO-quote.php
	 */
	public function quoteString($str)
	{
		if($this->getActive())
			return $this->_pdo->quote($str);
		else
			throw new TDbException('dbconnection_connection_inactive');
	}

	/**
	 * Quotes a table name for use in a query.
	 * @param string $name table name
	 * @return string the properly quoted table name
	 */
	public function quoteTableName($name)
	{
		return $this->getDbMetaData()->quoteTableName($name);
	}

	/**
	 * Quotes a column name for use in a query.
	 * @param string $name column name
	 * @return string the properly quoted column name
	 */
	public function quoteColumnName($name)
	{
		return $this->getDbMetaData()->quoteColumnName($name);
	}

	/**
	 * Quotes a column alias for use in a query.
	 * @param string $name column name
	 * @return string the properly quoted column alias
	 */
	public function quoteColumnAlias($name)
	{
		return $this->getDbMetaData()->quoteColumnAlias($name);
	}

	/**
	 * @return TDbMetaData
	 */
	public function getDbMetaData()
	{
		if($this->_dbMeta===null)
		{
			Prado::using('System.Data.Common.TDbMetaData');
			$this->_dbMeta = TDbMetaData::getInstance($this);
		}
		return $this->_dbMeta;
	}

	/**
	 * @return TDbColumnCaseMode the case of the column names
	 */
	public function getColumnCase()
	{
		switch($this->getAttribute(PDO::ATTR_CASE))
		{
			case PDO::CASE_NATURAL:
				return TDbColumnCaseMode::Preserved;
			case PDO::CASE_LOWER:
				return TDbColumnCaseMode::LowerCase;
			case PDO::CASE_UPPER:
				return TDbColumnCaseMode::UpperCase;
		}
	}

	/**
	 * @param TDbColumnCaseMode the case of the column names
	 */
	public function setColumnCase($value)
	{
		switch(TPropertyValue::ensureEnum($value,'TDbColumnCaseMode'))
		{
			case TDbColumnCaseMode::Preserved:
				$value=PDO::CASE_NATURAL;
				break;
			case TDbColumnCaseMode::LowerCase:
				$value=PDO::CASE_LOWER;
				break;
			case TDbColumnCaseMode::UpperCase:
				$value=PDO::CASE_UPPER;
				break;
		}
		$this->setAttribute(PDO::ATTR_CASE,$value);
	}

	/**
	 * @return TDbNullConversionMode how the null and empty strings are converted
	 */
	public function getNullConversion()
	{
		switch($this->getAttribute(PDO::ATTR_ORACLE_NULLS))
		{
			case PDO::NULL_NATURAL:
				return TDbNullConversionMode::Preserved;
			case PDO::NULL_EMPTY_STRING:
				return TDbNullConversionMode::EmptyStringToNull;
			case PDO::NULL_TO_STRING:
				return TDbNullConversionMode::NullToEmptyString;
		}
	}

	/**
	 * @param TDbNullConversionMode how the null and empty strings are converted
	 */
	public function setNullConversion($value)
	{
		switch(TPropertyValue::ensureEnum($value,'TDbNullConversionMode'))
		{
			case TDbNullConversionMode::Preserved:
				$value=PDO::NULL_NATURAL;
				break;
			case TDbNullConversionMode::EmptyStringToNull:
				$value=PDO::NULL_EMPTY_STRING;
				break;
			case TDbNullConversionMode::NullToEmptyString:
				$value=PDO::NULL_TO_STRING;
				break;
		}
		$this->setAttribute(PDO::ATTR_ORACLE_NULLS,$value);
	}

	/**
	 * @return boolean whether creating or updating a DB record will be automatically committed.
	 * Some DBMS (such as sqlite) may not support this feature.
	 */
	public function getAutoCommit()
	{
		return $this->getAttribute(PDO::ATTR_AUTOCOMMIT);
	}

	/**
	 * @param boolean whether creating or updating a DB record will be automatically committed.
	 * Some DBMS (such as sqlite) may not support this feature.
	 */
	public function setAutoCommit($value)
	{
		$this->setAttribute(PDO::ATTR_AUTOCOMMIT,TPropertyValue::ensureBoolean($value));
	}

	/**
	 * @return boolean whether the connection is persistent or not
	 * Some DBMS (such as sqlite) may not support this feature.
	 */
	public function getPersistent()
	{
		return $this->getAttribute(PDO::ATTR_PERSISTENT);
	}

	/**
	 * @param boolean whether the connection is persistent or not
	 * Some DBMS (such as sqlite) may not support this feature.
	 */
	public function setPersistent($value)
	{
		return $this->setAttribute(PDO::ATTR_PERSISTENT,TPropertyValue::ensureBoolean($value));
	}

	/**
	 * @return string name of the DB driver
	 */
	public function getDriverName()
	{
		return $this->getAttribute(PDO::ATTR_DRIVER_NAME);
	}

	/**
	 * @return string the version information of the DB driver
	 */
	public function getClientVersion()
	{
		return $this->getAttribute(PDO::ATTR_CLIENT_VERSION);
	}

	/**
	 * @return string the status of the connection
	 * Some DBMS (such as sqlite) may not support this feature.
	 */
	public function getConnectionStatus()
	{
		return $this->getAttribute(PDO::ATTR_CONNECTION_STATUS);
	}

	/**
	 * @return boolean whether the connection performs data prefetching
	 */
	public function getPrefetch()
	{
		return $this->getAttribute(PDO::ATTR_PREFETCH);
	}

	/**
	 * @return string the information of DBMS server
	 */
	public function getServerInfo()
	{
		return $this->getAttribute(PDO::ATTR_SERVER_INFO);
	}

	/**
	 * @return string the version information of DBMS server
	 */
	public function getServerVersion()
	{
		return $this->getAttribute(PDO::ATTR_SERVER_VERSION);
	}

	/**
	 * @return int timeout settings for the connection
	 */
	public function getTimeout()
	{
		return $this->getAttribute(PDO::ATTR_TIMEOUT);
	}

	/**
	 * Obtains a specific DB connection attribute information.
	 * @param int the attribute to be queried
	 * @return mixed the corresponding attribute information
	 * @see http://www.php.net/manual/en/function.PDO-getAttribute.php
	 */
	public function getAttribute($name)
	{
		if($this->getActive())
			return $this->_pdo->getAttribute($name);
		else
			throw new TDbException('dbconnection_connection_inactive');
	}

	/**
	 * Sets an attribute on the database connection.
	 * @param int the attribute to be set
	 * @param mixed the attribute value
	 * @see http://www.php.net/manual/en/function.PDO-setAttribute.php
	 */
	public function setAttribute($name,$value)
	{
		if($this->_pdo instanceof PDO)
			$this->_pdo->setAttribute($name,$value);
		else
			$this->_attributes[$name]=$value;
	}
}

/**
 * TDbColumnCaseMode
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @version $Id: TDbConnection.php 3245 2013-01-07 20:23:32Z ctrlaltca $
 * @package System.Data
 * @since 3.0
 */
class TDbColumnCaseMode extends TEnumerable
{
	/**
	 * Column name cases are kept as is from the database
	 */
	const Preserved='Preserved';
	/**
	 * Column names are converted to lower case
	 */
	const LowerCase='LowerCase';
	/**
	 * Column names are converted to upper case
	 */
	const UpperCase='UpperCase';
}

/**
 * TDbNullConversionMode
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @version $Id: TDbConnection.php 3245 2013-01-07 20:23:32Z ctrlaltca $
 * @package System.Data
 * @since 3.0
 */
class TDbNullConversionMode extends TEnumerable
{
	/**
	 * No conversion is performed for null and empty values.
	 */
	const Preserved='Preserved';
	/**
	 * NULL is converted to empty string
	 */
	const NullToEmptyString='NullToEmptyString';
	/**
	 * Empty string is converted to NULL
	 */
	const EmptyStringToNull='EmptyStringToNull';
}