includes/db/ORMTable.php

   1 <?php
   2 /**
   3  * Abstract base class for representing a single database table.
   4  * Documentation inline and at https://www.mediawiki.org/wiki/Manual:ORMTable
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  19  * http://www.gnu.org/copyleft/gpl.html
  20  *
  21  * @since 1.20
  22  * Non-abstract since 1.21
  23  *
  24  * @file ORMTable.php
  25  * @ingroup ORM
  26  *
  27  * @license GNU GPL v2 or later
  28  * @author Jeroen De Dauw < jeroendedauw@gmail.com >
  29  */
  30
  31 class ORMTable extends DBAccessBase implements IORMTable {
  32
  33         /**
  34          * Cache for instances, used by the singleton method.
  35          *
  36          * @since 1.20
  37          * @deprecated since 1.21
  38          *
  39          * @var ORMTable[]
  40          */
  41         protected static $instanceCache = array();
  42
  43         /**
  44          * @since 1.21
  45          *
  46          * @var string
  47          */
  48         protected $tableName;
  49
  50         /**
  51          * @since 1.21
  52          *
  53          * @var string[]
  54          */
  55         protected $fields = array();
  56
  57         /**
  58          * @since 1.21
  59          *
  60          * @var string
  61          */
  62         protected $fieldPrefix = '';
  63
  64         /**
  65          * @since 1.21
  66          *
  67          * @var string
  68          */
  69         protected $rowClass = 'ORMRow';
  70
  71         /**
  72          * @since 1.21
  73          *
  74          * @var array
  75          */
  76         protected $defaults = array();
  77
  78         /**
  79          * ID of the database connection to use for read operations.
  80          * Can be changed via @see setReadDb.
  81          *
  82          * @since 1.20
  83          *
  84          * @var integer DB_ enum
  85          */
  86         protected $readDb = DB_SLAVE;
  87
  88         /**
  89          * Constructor.
  90          *
  91          * @since 1.21
  92          *
  93          * @param string $tableName
  94          * @param string[] $fields
  95          * @param array $defaults
  96          * @param string|null $rowClass
  97          * @param string $fieldPrefix
  98          */
  99         public function __construct( $tableName = '', array $fields = array(), array $defaults = array(), $rowClass = null, $fieldPrefix = '' ) {
 100                 $this->tableName = $tableName;
 101                 $this->fields = $fields;
 102                 $this->defaults = $defaults;
 103
 104                 if ( is_string( $rowClass ) ) {
 105                         $this->rowClass = $rowClass;
 106                 }
 107
 108                 $this->fieldPrefix = $fieldPrefix;
 109         }
 110
 111         /**
 112          * @see IORMTable::getName
 113          *
 114          * @since 1.21
 115          *
 116          * @return string
 117          * @throws MWException
 118          */
 119         public function getName() {
 120                 if ( $this->tableName === '' ) {
 121                         throw new MWException( 'The table name needs to be set' );
 122                 }
 123
 124                 return $this->tableName;
 125         }
 126
 127         /**
 128          * Gets the db field prefix.
 129          *
 130          * @since 1.20
 131          *
 132          * @return string
 133          */
 134         protected function getFieldPrefix() {
 135                 return $this->fieldPrefix;
 136         }
 137
 138         /**
 139          * @see IORMTable::getRowClass
 140          *
 141          * @since 1.21
 142          *
 143          * @return string
 144          */
 145         public function getRowClass() {
 146                 return $this->rowClass;
 147         }
 148
 149         /**
 150          * @see ORMTable::getFields
 151          *
 152          * @since 1.21
 153          *
 154          * @return array
 155          * @throws MWException
 156          */
 157         public function getFields() {
 158                 if ( $this->fields === array() ) {
 159                         throw new MWException( 'The table needs to have one or more fields' );
 160                 }
 161
 162                 return $this->fields;
 163         }
 164
 165         /**
 166          * Returns a list of default field values.
 167          * field name => field value
 168          *
 169          * @since 1.20
 170          *
 171          * @return array
 172          */
 173         public function getDefaults() {
 174                 return $this->defaults;
 175         }
 176
 177         /**
 178          * Returns a list of the summary fields.
 179          * These are fields that cache computed values, such as the amount of linked objects of $type.
 180          * This is relevant as one might not want to do actions such as log changes when these get updated.
 181          *
 182          * @since 1.20
 183          *
 184          * @return array
 185          */
 186         public function getSummaryFields() {
 187                 return array();
 188         }
 189
 190         /**
 191          * Selects the the specified fields of the records matching the provided
 192          * conditions and returns them as DBDataObject. Field names get prefixed.
 193          *
 194          * @since 1.20
 195          *
 196          * @param array|string|null $fields
 197          * @param array $conditions
 198          * @param array $options
 199          * @param string|null $functionName
 200          *
 201          * @return ORMResult
 202          */
 203         public function select( $fields = null, array $conditions = array(),
 204                                                         array $options = array(), $functionName = null ) {
 205                 $res = $this->rawSelect( $fields, $conditions, $options, $functionName );
 206                 return new ORMResult( $this, $res );
 207         }
 208
 209         /**
 210          * Selects the the specified fields of the records matching the provided
 211          * conditions and returns them as DBDataObject. Field names get prefixed.
 212          *
 213          * @since 1.20
 214          *
 215          * @param array|string|null $fields
 216          * @param array $conditions
 217          * @param array $options
 218          * @param string|null $functionName
 219          *
 220          * @return array of row objects
 221          * @throws DBQueryError if the query failed (even if the database was in ignoreErrors mode).
 222          */
 223         public function selectObjects( $fields = null, array $conditions = array(),
 224                                                                    array $options = array(), $functionName = null ) {
 225                 $result = $this->selectFields( $fields, $conditions, $options, false, $functionName );
 226
 227                 $objects = array();
 228
 229                 foreach ( $result as $record ) {
 230                         $objects[] = $this->newRow( $record );
 231                 }
 232
 233                 return $objects;
 234         }
 235
 236         /**
 237          * Do the actual select.
 238          *
 239          * @since 1.20
 240          *
 241          * @param null|string|array $fields
 242          * @param array             $conditions
 243          * @param array             $options
 244          * @param null|string       $functionName
 245          *
 246          * @return ResultWrapper
 247          * @throws DBQueryError if the quey failed (even if the database was in ignoreErrors mode).
 248          */
 249         public function rawSelect( $fields = null, array $conditions = array(),
 250                                                            array $options = array(), $functionName = null ) {
 251                 if ( is_null( $fields ) ) {
 252                         $fields = array_keys( $this->getFields() );
 253                 }
 254                 else {
 255                         $fields = (array)$fields;
 256                 }
 257
 258                 $dbr = $this->getReadDbConnection();
 259                 $result = $dbr->select(
 260                         $this->getName(),
 261                         $this->getPrefixedFields( $fields ),
 262                         $this->getPrefixedValues( $conditions ),
 263                         is_null( $functionName ) ? __METHOD__ : $functionName,
 264                         $options
 265                 );
 266
 267                 /* @var Exception $error */
 268                 $error = null;
 269
 270                 if ( $result === false ) {
 271                         // Database connection was in "ignoreErrors" mode. We don't like that.
 272                         // So, we emulate the DBQueryError that should have been thrown.
 273                         $error = new DBQueryError(
 274                                 $dbr,
 275                                 $dbr->lastError(),
 276                                 $dbr->lastErrno(),
 277                                 $dbr->lastQuery(),
 278                                 is_null( $functionName ) ? __METHOD__ : $functionName
 279                         );
 280                 }
 281
 282                 $this->releaseConnection( $dbr );
 283
 284                 if ( $error ) {
 285                         // Note: construct the error before releasing the connection,
 286                         // but throw it after.
 287                         throw $error;
 288                 }
 289
 290                 return $result;
 291         }
 292
 293         /**
 294          * Selects the the specified fields of the records matching the provided
 295          * conditions and returns them as associative arrays.
 296          * Provided field names get prefixed.
 297          * Returned field names will not have a prefix.
 298          *
 299          * When $collapse is true:
 300          * If one field is selected, each item in the result array will be this field.
 301          * If two fields are selected, each item in the result array will have as key
 302          * the first field and as value the second field.
 303          * If more then two fields are selected, each item will be an associative array.
 304          *
 305          * @since 1.20
 306          *
 307          * @param array|string|null $fields
 308          * @param array $conditions
 309          * @param array $options
 310          * @param boolean $collapse Set to false to always return each result row as associative array.
 311          * @param string|null $functionName
 312          *
 313          * @return array of array
 314          */
 315         public function selectFields( $fields = null, array $conditions = array(),
 316                                                                   array $options = array(), $collapse = true, $functionName = null ) {
 317                 $objects = array();
 318
 319                 $result = $this->rawSelect( $fields, $conditions, $options, $functionName );
 320
 321                 foreach ( $result as $record ) {
 322                         $objects[] = $this->getFieldsFromDBResult( $record );
 323                 }
 324
 325                 if ( $collapse ) {
 326                         if ( count( $fields ) === 1 ) {
 327                                 $objects = array_map( 'array_shift', $objects );
 328                         }
 329                         elseif ( count( $fields ) === 2 ) {
 330                                 $o = array();
 331
 332                                 foreach ( $objects as $object ) {
 333                                         $o[array_shift( $object )] = array_shift( $object );
 334                                 }
 335
 336                                 $objects = $o;
 337                         }
 338                 }
 339
 340                 return $objects;
 341         }
 342
 343         /**
 344          * Selects the the specified fields of the first matching record.
 345          * Field names get prefixed.
 346          *
 347          * @since 1.20
 348          *
 349          * @param array|string|null $fields
 350          * @param array $conditions
 351          * @param array $options
 352          * @param string|null $functionName
 353          *
 354          * @return IORMRow|bool False on failure
 355          */
 356         public function selectRow( $fields = null, array $conditions = array(),
 357                                                            array $options = array(), $functionName = null ) {
 358                 $options['LIMIT'] = 1;
 359
 360                 $objects = $this->select( $fields, $conditions, $options, $functionName );
 361
 362                 return ( !$objects || $objects->isEmpty() ) ? false : $objects->current();
 363         }
 364
 365         /**
 366          * Selects the the specified fields of the records matching the provided
 367          * conditions. Field names do NOT get prefixed.
 368          *
 369          * @since 1.20
 370          *
 371          * @param array $fields
 372          * @param array $conditions
 373          * @param array $options
 374          * @param string|null $functionName
 375          *
 376          * @return ResultWrapper
 377          */
 378         public function rawSelectRow( array $fields, array $conditions = array(),
 379                                                                   array $options = array(), $functionName = null ) {
 380                 $dbr = $this->getReadDbConnection();
 381
 382                 $result = $dbr->selectRow(
 383                         $this->getName(),
 384                         $fields,
 385                         $conditions,
 386                         is_null( $functionName ) ? __METHOD__ : $functionName,
 387                         $options
 388                 );
 389
 390                 $this->releaseConnection( $dbr );
 391                 return $result;
 392         }
 393
 394         /**
 395          * Selects the the specified fields of the first record matching the provided
 396          * conditions and returns it as an associative array, or false when nothing matches.
 397          * This method makes use of selectFields and expects the same parameters and
 398          * returns the same results (if there are any, if there are none, this method returns false).
 399          * @see ORMTable::selectFields
 400          *
 401          * @since 1.20
 402          *
 403          * @param array|string|null $fields
 404          * @param array $conditions
 405          * @param array $options
 406          * @param boolean $collapse Set to false to always return each result row as associative array.
 407          * @param string|null $functionName
 408          *
 409          * @return mixed|array|bool False on failure
 410          */
 411         public function selectFieldsRow( $fields = null, array $conditions = array(),
 412                                                                          array $options = array(), $collapse = true, $functionName = null ) {
 413                 $options['LIMIT'] = 1;
 414
 415                 $objects = $this->selectFields( $fields, $conditions, $options, $collapse, $functionName );
 416
 417                 return empty( $objects ) ? false : $objects[0];
 418         }
 419
 420         /**
 421          * Returns if there is at least one record matching the provided conditions.
 422          * Condition field names get prefixed.
 423          *
 424          * @since 1.20
 425          *
 426          * @param array $conditions
 427          *
 428          * @return boolean
 429          */
 430         public function has( array $conditions = array() ) {
 431                 return $this->selectRow( array( 'id' ), $conditions ) !== false;
 432         }
 433
 434         /**
 435          * Checks if the table exists
 436          *
 437          * @since 1.21
 438          *
 439          * @return boolean
 440          */
 441         public function exists() {
 442                 $dbr = $this->getReadDbConnection();
 443                 $exists = $dbr->tableExists( $this->getName() );
 444                 $this->releaseConnection( $dbr );
 445
 446                 return $exists;
 447         }
 448
 449         /**
 450          * Returns the amount of matching records.
 451          * Condition field names get prefixed.
 452          *
 453          * Note that this can be expensive on large tables.
 454          * In such cases you might want to use DatabaseBase::estimateRowCount instead.
 455          *
 456          * @since 1.20
 457          *
 458          * @param array $conditions
 459          * @param array $options
 460          *
 461          * @return integer
 462          */
 463         public function count( array $conditions = array(), array $options = array() ) {
 464                 $res = $this->rawSelectRow(
 465                         array( 'rowcount' => 'COUNT(*)' ),
 466                         $this->getPrefixedValues( $conditions ),
 467                         $options,
 468                         __METHOD__
 469                 );
 470
 471                 return $res->rowcount;
 472         }
 473
 474         /**
 475          * Removes the object from the database.
 476          *
 477          * @since 1.20
 478          *
 479          * @param array $conditions
 480          * @param string|null $functionName
 481          *
 482          * @return boolean Success indicator
 483          */
 484         public function delete( array $conditions, $functionName = null ) {
 485                 $dbw = $this->getWriteDbConnection();
 486
 487                 $result = $dbw->delete(
 488                         $this->getName(),
 489                         $conditions === array() ? '*' : $this->getPrefixedValues( $conditions ),
 490                         is_null( $functionName ) ? __METHOD__ : $functionName
 491                 ) !== false; // DatabaseBase::delete does not always return true for success as documented...
 492
 493                 $this->releaseConnection( $dbw );
 494                 return $result;
 495         }
 496
 497         /**
 498          * Get API parameters for the fields supported by this object.
 499          *
 500          * @since 1.20
 501          *
 502          * @param boolean $requireParams
 503          * @param boolean $setDefaults
 504          *
 505          * @return array
 506          */
 507         public function getAPIParams( $requireParams = false, $setDefaults = false ) {
 508                 $typeMap = array(
 509                         'id' => 'integer',
 510                         'int' => 'integer',
 511                         'float' => 'NULL',
 512                         'str' => 'string',
 513                         'bool' => 'integer',
 514                         'array' => 'string',
 515                         'blob' => 'string',
 516                 );
 517
 518                 $params = array();
 519                 $defaults = $this->getDefaults();
 520
 521                 foreach ( $this->getFields() as $field => $type ) {
 522                         if ( $field == 'id' ) {
 523                                 continue;
 524                         }
 525
 526                         $hasDefault = array_key_exists( $field, $defaults );
 527
 528                         $params[$field] = array(
 529                                 ApiBase::PARAM_TYPE => $typeMap[$type],
 530                                 ApiBase::PARAM_REQUIRED => $requireParams && !$hasDefault
 531                         );
 532
 533                         if ( $type == 'array' ) {
 534                                 $params[$field][ApiBase::PARAM_ISMULTI] = true;
 535                         }
 536
 537                         if ( $setDefaults && $hasDefault ) {
 538                                 $default = is_array( $defaults[$field] ) ? implode( '|', $defaults[$field] ) : $defaults[$field];
 539                                 $params[$field][ApiBase::PARAM_DFLT] = $default;
 540                         }
 541                 }
 542
 543                 return $params;
 544         }
 545
 546         /**
 547          * Returns an array with the fields and their descriptions.
 548          *
 549          * field name => field description
 550          *
 551          * @since 1.20
 552          *
 553          * @return array
 554          */
 555         public function getFieldDescriptions() {
 556                 return array();
 557         }
 558
 559         /**
 560          * Get the database ID used for read operations.
 561          *
 562          * @since 1.20
 563          *
 564          * @return integer DB_ enum
 565          */
 566         public function getReadDb() {
 567                 return $this->readDb;
 568         }
 569
 570         /**
 571          * Set the database ID to use for read operations, use DB_XXX constants or an index to the load balancer setup.
 572          *
 573          * @param integer $db
 574          *
 575          * @since 1.20
 576          */
 577         public function setReadDb( $db ) {
 578                 $this->readDb = $db;
 579         }
 580
 581         /**
 582          * Get the ID of the any foreign wiki to use as a target for database operations
 583          *
 584          * @since 1.20
 585          *
 586          * @return String|bool The target wiki, in a form that  LBFactory understands (or false if the local wiki is used)
 587          */
 588         public function getTargetWiki() {
 589                 return $this->wiki;
 590         }
 591
 592         /**
 593          * Set the ID of the any foreign wiki to use as a target for database operations
 594          *
 595          * @param string|bool $wiki The target wiki, in a form that  LBFactory understands (or false if the local wiki shall be used)
 596          *
 597          * @since 1.20
 598          */
 599         public function setTargetWiki( $wiki ) {
 600                 $this->wiki = $wiki;
 601         }
 602
 603         /**
 604          * Get the database type used for read operations.
 605          * This is to be used instead of wfGetDB.
 606          *
 607          * @see LoadBalancer::getConnection
 608          *
 609          * @since 1.20
 610          *
 611          * @return DatabaseBase The database object
 612          */
 613         public function getReadDbConnection() {
 614                 return $this->getConnection( $this->getReadDb(), array() );
 615         }
 616
 617         /**
 618          * Get the database type used for read operations.
 619          * This is to be used instead of wfGetDB.
 620          *
 621          * @see LoadBalancer::getConnection
 622          *
 623          * @since 1.20
 624          *
 625          * @return DatabaseBase The database object
 626          */
 627         public function getWriteDbConnection() {
 628                 return $this->getConnection( DB_MASTER, array() );
 629         }
 630
 631         /**
 632          * Releases the lease on the given database connection. This is useful mainly
 633          * for connections to a foreign wiki. It does nothing for connections to the local wiki.
 634          *
 635          * @see LoadBalancer::reuseConnection
 636          *
 637          * @param DatabaseBase $db the database
 638          *
 639          * @since 1.20
 640          */
 641         public function releaseConnection( DatabaseBase $db ) {
 642                 parent::releaseConnection( $db ); // just make it public
 643         }
 644
 645         /**
 646          * Update the records matching the provided conditions by
 647          * setting the fields that are keys in the $values param to
 648          * their corresponding values.
 649          *
 650          * @since 1.20
 651          *
 652          * @param array $values
 653          * @param array $conditions
 654          *
 655          * @return boolean Success indicator
 656          */
 657         public function update( array $values, array $conditions = array() ) {
 658                 $dbw = $this->getWriteDbConnection();
 659
 660                 $result = $dbw->update(
 661                         $this->getName(),
 662                         $this->getPrefixedValues( $values ),
 663                         $this->getPrefixedValues( $conditions ),
 664                         __METHOD__
 665                 ) !== false; // DatabaseBase::update does not always return true for success as documented...
 666
 667                 $this->releaseConnection( $dbw );
 668                 return $result;
 669         }
 670
 671         /**
 672          * Computes the values of the summary fields of the objects matching the provided conditions.
 673          *
 674          * @since 1.20
 675          *
 676          * @param array|string|null $summaryFields
 677          * @param array $conditions
 678          */
 679         public function updateSummaryFields( $summaryFields = null, array $conditions = array() ) {
 680                 $slave = $this->getReadDb();
 681                 $this->setReadDb( DB_MASTER );
 682
 683                 /**
 684                  * @var IORMRow $item
 685                  */
 686                 foreach ( $this->select( null, $conditions ) as $item ) {
 687                         $item->loadSummaryFields( $summaryFields );
 688                         $item->setSummaryMode( true );
 689                         $item->save();
 690                 }
 691
 692                 $this->setReadDb( $slave );
 693         }
 694
 695         /**
 696          * Takes in an associative array with field names as keys and
 697          * their values as value. The field names are prefixed with the
 698          * db field prefix.
 699          *
 700          * @since 1.20
 701          *
 702          * @param array $values
 703          *
 704          * @return array
 705          */
 706         public function getPrefixedValues( array $values ) {
 707                 $prefixedValues = array();
 708
 709                 foreach ( $values as $field => $value ) {
 710                         if ( is_integer( $field ) ) {
 711                                 if ( is_array( $value ) ) {
 712                                         $field = $value[0];
 713                                         $value = $value[1];
 714                                 }
 715                                 else {
 716                                         $value = explode( ' ', $value, 2 );
 717                                         $value[0] = $this->getPrefixedField( $value[0] );
 718                                         $prefixedValues[] = implode( ' ', $value );
 719                                         continue;
 720                                 }
 721                         }
 722
 723                         $prefixedValues[$this->getPrefixedField( $field )] = $value;
 724                 }
 725
 726                 return $prefixedValues;
 727         }
 728
 729         /**
 730          * Takes in a field or array of fields and returns an
 731          * array with their prefixed versions, ready for db usage.
 732          *
 733          * @since 1.20
 734          *
 735          * @param array|string $fields
 736          *
 737          * @return array
 738          */
 739         public function getPrefixedFields( array $fields ) {
 740                 foreach ( $fields as &$field ) {
 741                         $field = $this->getPrefixedField( $field );
 742                 }
 743
 744                 return $fields;
 745         }
 746
 747         /**
 748          * Takes in a field and returns an it's prefixed version, ready for db usage.
 749          *
 750          * @since 1.20
 751          *
 752          * @param string|array $field
 753          *
 754          * @return string
 755          */
 756         public function getPrefixedField( $field ) {
 757                 return $this->getFieldPrefix() . $field;
 758         }
 759
 760         /**
 761          * Takes an array of field names with prefix and returns the unprefixed equivalent.
 762          *
 763          * @since 1.20
 764          *
 765          * @param array $fieldNames
 766          *
 767          * @return array
 768          */
 769         public function unprefixFieldNames( array $fieldNames ) {
 770                 return array_map( array( $this, 'unprefixFieldName' ), $fieldNames );
 771         }
 772
 773         /**
 774          * Takes a field name with prefix and returns the unprefixed equivalent.
 775          *
 776          * @since 1.20
 777          *
 778          * @param string $fieldName
 779          *
 780          * @return string
 781          */
 782         public function unprefixFieldName( $fieldName ) {
 783                 return substr( $fieldName, strlen( $this->getFieldPrefix() ) );
 784         }
 785
 786         /**
 787          * Get an instance of this class.
 788          *
 789          * @since 1.20
 790          * @deprecated since 1.21
 791          *
 792          * @return IORMTable
 793          */
 794         public static function singleton() {
 795                 $class = get_called_class();
 796
 797                 if ( !array_key_exists( $class, self::$instanceCache ) ) {
 798                         self::$instanceCache[$class] = new $class;
 799                 }
 800
 801                 return self::$instanceCache[$class];
 802         }
 803
 804         /**
 805          * Get an array with fields from a database result,
 806          * that can be fed directly to the constructor or
 807          * to setFields.
 808          *
 809          * @since 1.20
 810          *
 811          * @param stdClass $result
 812          *
 813          * @return array
 814          */
 815         public function getFieldsFromDBResult( stdClass $result ) {
 816                 $result = (array)$result;
 817
 818                 $rawFields = array_combine(
 819                         $this->unprefixFieldNames( array_keys( $result ) ),
 820                         array_values( $result )
 821                 );
 822
 823                 $fieldDefinitions = $this->getFields();
 824                 $fields = array();
 825
 826                 foreach ( $rawFields as $name => $value ) {
 827                         if ( array_key_exists( $name, $fieldDefinitions ) ) {
 828                                 switch ( $fieldDefinitions[$name] ) {
 829                                         case 'int':
 830                                                 $value = (int)$value;
 831                                                 break;
 832                                         case 'float':
 833                                                 $value = (float)$value;
 834                                                 break;
 835                                         case 'bool':
 836                                                 if ( is_string( $value ) ) {
 837                                                         $value = $value !== '0';
 838                                                 } elseif ( is_int( $value ) ) {
 839                                                         $value = $value !== 0;
 840                                                 }
 841                                                 break;
 842                                         case 'array':
 843                                                 if ( is_string( $value ) ) {
 844                                                         $value = unserialize( $value );
 845                                                 }
 846
 847                                                 if ( !is_array( $value ) ) {
 848                                                         $value = array();
 849                                                 }
 850                                                 break;
 851                                         case 'blob':
 852                                                 if ( is_string( $value ) ) {
 853                                                         $value = unserialize( $value );
 854                                                 }
 855                                                 break;
 856                                         case 'id':
 857                                                 if ( is_string( $value ) ) {
 858                                                         $value = (int)$value;
 859                                                 }
 860                                                 break;
 861                                 }
 862
 863                                 $fields[$name] = $value;
 864                         } else {
 865                                 throw new MWException( 'Attempted to set unknown field ' . $name );
 866                         }
 867                 }
 868
 869                 return $fields;
 870         }
 871
 872         /**
 873          * @see ORMTable::newRowFromFromDBResult
 874          *
 875          * @deprecated use newRowFromDBResult instead
 876          * @since 1.20
 877          *
 878          * @param stdClass $result
 879          *
 880          * @return IORMRow
 881          */
 882         public function newFromDBResult( stdClass $result ) {
 883                 return self::newRowFromDBResult( $result );
 884         }
 885
 886         /**
 887          * Get a new instance of the class from a database result.
 888          *
 889          * @since 1.20
 890          *
 891          * @param stdClass $result
 892          *
 893          * @return IORMRow
 894          */
 895         public function newRowFromDBResult( stdClass $result ) {
 896                 return $this->newRow( $this->getFieldsFromDBResult( $result ) );
 897         }
 898
 899         /**
 900          * @see ORMTable::newRow
 901          *
 902          * @deprecated use newRow instead
 903          * @since 1.20
 904          *
 905          * @param array $data
 906          * @param boolean $loadDefaults
 907          *
 908          * @return IORMRow
 909          */
 910         public function newFromArray( array $data, $loadDefaults = false ) {
 911                 return static::newRow( $data, $loadDefaults );
 912         }
 913
 914         /**
 915          * Get a new instance of the class from an array.
 916          *
 917          * @since 1.20
 918          *
 919          * @param array $fields
 920          * @param boolean $loadDefaults
 921          *
 922          * @return IORMRow
 923          */
 924         public function newRow( array $fields, $loadDefaults = false ) {
 925                 $class = $this->getRowClass();
 926
 927                 return new $class( $this, $fields, $loadDefaults );
 928         }
 929
 930         /**
 931          * Return the names of the fields.
 932          *
 933          * @since 1.20
 934          *
 935          * @return array
 936          */
 937         public function getFieldNames() {
 938                 return array_keys( $this->getFields() );
 939         }
 940
 941         /**
 942          * Gets if the object can take a certain field.
 943          *
 944          * @since 1.20
 945          *
 946          * @param string $name
 947          *
 948          * @return boolean
 949          */
 950         public function canHaveField( $name ) {
 951                 return array_key_exists( $name, $this->getFields() );
 952         }
 953
 954         /**
 955          * Updates the provided row in the database.
 956          *
 957          * @since 1.22
 958          *
 959          * @param IORMRow $row The row to save
 960          * @param string|null $functionName
 961          *
 962          * @return boolean Success indicator
 963          */
 964         public function updateRow( IORMRow $row, $functionName = null ) {
 965                 $dbw = $this->getWriteDbConnection();
 966
 967                 $success = $dbw->update(
 968                         $this->getName(),
 969                         $this->getWriteValues( $row ),
 970                         $this->getPrefixedValues( array( 'id' => $row->getId() ) ),
 971                         is_null( $functionName ) ? __METHOD__ : $functionName
 972                 );
 973
 974                 $this->releaseConnection( $dbw );
 975
 976                 // DatabaseBase::update does not always return true for success as documented...
 977                 return $success !== false;
 978         }
 979
 980         /**
 981          * Inserts the provided row into the database.
 982          *
 983          * @since 1.22
 984          *
 985          * @param IORMRow $row
 986          * @param string|null $functionName
 987          * @param array|null $options
 988          *
 989          * @return boolean Success indicator
 990          */
 991         public function insertRow( IORMRow $row, $functionName = null, array $options = null ) {
 992                 $dbw = $this->getWriteDbConnection();
 993
 994                 $success = $dbw->insert(
 995                         $this->getName(),
 996                         $this->getWriteValues( $row ),
 997                         is_null( $functionName ) ? __METHOD__ : $functionName,
 998                         $options
 999                 );
1000
1001                 // DatabaseBase::insert does not always return true for success as documented...
1002                 $success = $success !== false;
1003
1004                 if ( $success ) {
1005                         $row->setField( 'id', $dbw->insertId() );
1006                 }
1007
1008                 $this->releaseConnection( $dbw );
1009
1010                 return $success;
1011         }
1012
1013         /**
1014          * Gets the fields => values to write to the table.
1015          *
1016          * @since 1.22
1017          *
1018          * @param IORMRow $row
1019          *
1020          * @return array
1021          */
1022         protected function getWriteValues( IORMRow $row ) {
1023                 $values = array();
1024
1025                 $rowFields = $row->getFields();
1026
1027                 foreach ( $this->getFields() as $name => $type ) {
1028                         if ( array_key_exists( $name, $rowFields ) ) {
1029                                 $value = $rowFields[$name];
1030
1031                                 switch ( $type ) {
1032                                         case 'array':
1033                                                 $value = (array)$value;
1034                                         // fall-through!
1035                                         case 'blob':
1036                                                 $value = serialize( $value );
1037                                         // fall-through!
1038                                 }
1039
1040                                 $values[$this->getPrefixedField( $name )] = $value;
1041                         }
1042                 }
1043
1044                 return $values;
1045         }
1046
1047         /**
1048          * Removes the provided row from the database.
1049          *
1050          * @since 1.22
1051          *
1052          * @param IORMRow $row
1053          * @param string|null $functionName
1054          *
1055          * @return boolean Success indicator
1056          */
1057         public function removeRow( IORMRow $row, $functionName = null ) {
1058                 $success = $this->delete(
1059                         array( 'id' => $row->getId() ),
1060                         is_null( $functionName ) ? __METHOD__ : $functionName
1061                 );
1062
1063                 // DatabaseBase::delete does not always return true for success as documented...
1064                 return $success !== false;
1065         }
1066
1067         /**
1068          * Add an amount (can be negative) to the specified field (needs to be numeric).
1069          *
1070          * @since 1.22
1071          *
1072          * @param array $conditions
1073          * @param string $field
1074          * @param integer $amount
1075          *
1076          * @return boolean Success indicator
1077          * @throws MWException
1078          */
1079         public function addToField( array $conditions, $field, $amount ) {
1080                 if ( !array_key_exists( $field, $this->fields ) ) {
1081                         throw new MWException( 'Unknown field "' . $field . '" provided' );
1082                 }
1083
1084                 if ( $amount == 0 ) {
1085                         return true;
1086                 }
1087
1088                 $absoluteAmount = abs( $amount );
1089                 $isNegative = $amount < 0;
1090
1091                 $fullField = $this->getPrefixedField( $field );
1092
1093                 $dbw = $this->getWriteDbConnection();
1094
1095                 $success = $dbw->update(
1096                         $this->getName(),
1097                         array( "$fullField=$fullField" . ( $isNegative ? '-' : '+' ) . $absoluteAmount ),
1098                         $this->getPrefixedValues( $conditions ),
1099                         __METHOD__
1100                 ) !== false; // DatabaseBase::update does not always return true for success as documented...
1101
1102                 $this->releaseConnection( $dbw );
1103
1104                 return $success;
1105         }
1106
1107 }