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          * Cache for instances, used by the singleton method.
  34          *
  35          * @since 1.20
  36          * @deprecated since 1.21
  37          *
  38          * @var ORMTable[]
  39          */
  40         protected static $instanceCache = array();
  41
  42         /**
  43          * @since 1.21
  44          *
  45          * @var string
  46          */
  47         protected $tableName;
  48
  49         /**
  50          * @since 1.21
  51          *
  52          * @var string[]
  53          */
  54         protected $fields = array();
  55
  56         /**
  57          * @since 1.21
  58          *
  59          * @var string
  60          */
  61         protected $fieldPrefix = '';
  62
  63         /**
  64          * @since 1.21
  65          *
  66          * @var string
  67          */
  68         protected $rowClass = 'ORMRow';
  69
  70         /**
  71          * @since 1.21
  72          *
  73          * @var array
  74          */
  75         protected $defaults = array();
  76
  77         /**
  78          * ID of the database connection to use for read operations.
  79          * Can be changed via @see setReadDb.
  80          *
  81          * @since 1.20
  82          *
  83          * @var int DB_ enum
  84          */
  85         protected $readDb = DB_SLAVE;
  86
  87         /**
  88          * Constructor.
  89          *
  90          * @since 1.21
  91          *
  92          * @param string $tableName
  93          * @param string[] $fields
  94          * @param array $defaults
  95          * @param string|null $rowClass
  96          * @param string $fieldPrefix
  97          */
  98         public function __construct( $tableName = '', array $fields = array(),
  99                 array $defaults = array(), $rowClass = null, $fieldPrefix = ''
 100         ) {
 101                 $this->tableName = $tableName;
 102                 $this->fields = $fields;
 103                 $this->defaults = $defaults;
 104
 105                 if ( is_string( $rowClass ) ) {
 106                         $this->rowClass = $rowClass;
 107                 }
 108
 109                 $this->fieldPrefix = $fieldPrefix;
 110         }
 111
 112         /**
 113          * @see IORMTable::getName
 114          *
 115          * @since 1.21
 116          *
 117          * @return string
 118          * @throws MWException
 119          */
 120         public function getName() {
 121                 if ( $this->tableName === '' ) {
 122                         throw new MWException( 'The table name needs to be set' );
 123                 }
 124
 125                 return $this->tableName;
 126         }
 127
 128         /**
 129          * Gets the db field prefix.
 130          *
 131          * @since 1.20
 132          *
 133          * @return string
 134          */
 135         protected function getFieldPrefix() {
 136                 return $this->fieldPrefix;
 137         }
 138
 139         /**
 140          * @see IORMTable::getRowClass
 141          *
 142          * @since 1.21
 143          *
 144          * @return string
 145          */
 146         public function getRowClass() {
 147                 return $this->rowClass;
 148         }
 149
 150         /**
 151          * @see ORMTable::getFields
 152          *
 153          * @since 1.21
 154          *
 155          * @return array
 156          * @throws MWException
 157          */
 158         public function getFields() {
 159                 if ( $this->fields === array() ) {
 160                         throw new MWException( 'The table needs to have one or more fields' );
 161                 }
 162
 163                 return $this->fields;
 164         }
 165
 166         /**
 167          * Returns a list of default field values.
 168          * field name => field value
 169          *
 170          * @since 1.20
 171          *
 172          * @return array
 173          */
 174         public function getDefaults() {
 175                 return $this->defaults;
 176         }
 177
 178         /**
 179          * Returns a list of the summary fields.
 180          * These are fields that cache computed values, such as the amount of linked objects of $type.
 181          * This is relevant as one might not want to do actions such as log changes when these get updated.
 182          *
 183          * @since 1.20
 184          *
 185          * @return array
 186          */
 187         public function getSummaryFields() {
 188                 return array();
 189         }
 190
 191         /**
 192          * Selects the the specified fields of the records matching the provided
 193          * conditions and returns them as DBDataObject. Field names get prefixed.
 194          *
 195          * @since 1.20
 196          *
 197          * @param array|string|null $fields
 198          * @param array $conditions
 199          * @param array $options
 200          * @param string|null $functionName
 201          *
 202          * @return ORMResult
 203          */
 204         public function select( $fields = null, array $conditions = array(),
 205                 array $options = array(), $functionName = null
 206         ) {
 207                 $res = $this->rawSelect( $fields, $conditions, $options, $functionName );
 208
 209                 return new ORMResult( $this, $res );
 210         }
 211
 212         /**
 213          * Selects the the specified fields of the records matching the provided
 214          * conditions and returns them as DBDataObject. Field names get prefixed.
 215          *
 216          * @since 1.20
 217          *
 218          * @param array|string|null $fields
 219          * @param array $conditions
 220          * @param array $options
 221          * @param string|null $functionName
 222          *
 223          * @return array Array of row objects
 224          * @throws DBQueryError If the query failed (even if the database was in ignoreErrors mode).
 225          */
 226         public function selectObjects( $fields = null, array $conditions = array(),
 227                 array $options = array(), $functionName = null
 228         ) {
 229                 $result = $this->selectFields( $fields, $conditions, $options, false, $functionName );
 230
 231                 $objects = array();
 232
 233                 foreach ( $result as $record ) {
 234                         $objects[] = $this->newRow( $record );
 235                 }
 236
 237                 return $objects;
 238         }
 239
 240         /**
 241          * Do the actual select.
 242          *
 243          * @since 1.20
 244          *
 245          * @param null|string|array $fields
 246          * @param array $conditions
 247          * @param array $options
 248          * @param null|string $functionName
 249          * @return ResultWrapper
 250          * @throws DBQueryError If the query failed (even if the database was in
 251          *   ignoreErrors mode).
 252          */
 253         public function rawSelect( $fields = null, array $conditions = array(),
 254                 array $options = array(), $functionName = null
 255         ) {
 256                 if ( is_null( $fields ) ) {
 257                         $fields = array_keys( $this->getFields() );
 258                 } else {
 259                         $fields = (array)$fields;
 260                 }
 261
 262                 $dbr = $this->getReadDbConnection();
 263                 $result = $dbr->select(
 264                         $this->getName(),
 265                         $this->getPrefixedFields( $fields ),
 266                         $this->getPrefixedValues( $conditions ),
 267                         is_null( $functionName ) ? __METHOD__ : $functionName,
 268                         $options
 269                 );
 270
 271                 /* @var Exception $error */
 272                 $error = null;
 273
 274                 if ( $result === false ) {
 275                         // Database connection was in "ignoreErrors" mode. We don't like that.
 276                         // So, we emulate the DBQueryError that should have been thrown.
 277                         $error = new DBQueryError(
 278                                 $dbr,
 279                                 $dbr->lastError(),
 280                                 $dbr->lastErrno(),
 281                                 $dbr->lastQuery(),
 282                                 is_null( $functionName ) ? __METHOD__ : $functionName
 283                         );
 284                 }
 285
 286                 $this->releaseConnection( $dbr );
 287
 288                 if ( $error ) {
 289                         // Note: construct the error before releasing the connection,
 290                         // but throw it after.
 291                         throw $error;
 292                 }
 293
 294                 return $result;
 295         }
 296
 297         /**
 298          * Selects the the specified fields of the records matching the provided
 299          * conditions and returns them as associative arrays.
 300          * Provided field names get prefixed.
 301          * Returned field names will not have a prefix.
 302          *
 303          * When $collapse is true:
 304          * If one field is selected, each item in the result array will be this field.
 305          * If two fields are selected, each item in the result array will have as key
 306          * the first field and as value the second field.
 307          * If more then two fields are selected, each item will be an associative array.
 308          *
 309          * @since 1.20
 310          *
 311          * @param array|string|null $fields
 312          * @param array $conditions
 313          * @param array $options
 314          * @param bool $collapse Set to false to always return each result row as associative array.
 315          * @param string|null $functionName
 316          *
 317          * @return array Array of array
 318          */
 319         public function selectFields( $fields = null, array $conditions = array(),
 320                 array $options = array(), $collapse = true, $functionName = null
 321         ) {
 322                 $objects = array();
 323
 324                 $result = $this->rawSelect( $fields, $conditions, $options, $functionName );
 325
 326                 foreach ( $result as $record ) {
 327                         $objects[] = $this->getFieldsFromDBResult( $record );
 328                 }
 329
 330                 if ( $collapse ) {
 331                         if ( count( $fields ) === 1 ) {
 332                                 $objects = array_map( 'array_shift', $objects );
 333                         } elseif ( count( $fields ) === 2 ) {
 334                                 $o = array();
 335
 336                                 foreach ( $objects as $object ) {
 337                                         $o[array_shift( $object )] = array_shift( $object );
 338                                 }
 339
 340                                 $objects = $o;
 341                         }
 342                 }
 343
 344                 return $objects;
 345         }
 346
 347         /**
 348          * Selects the the specified fields of the first matching record.
 349          * Field names get prefixed.
 350          *
 351          * @since 1.20
 352          *
 353          * @param array|string|null $fields
 354          * @param array $conditions
 355          * @param array $options
 356          * @param string|null $functionName
 357          *
 358          * @return IORMRow|bool False on failure
 359          */
 360         public function selectRow( $fields = null, array $conditions = array(),
 361                 array $options = array(), $functionName = null
 362         ) {
 363                 $options['LIMIT'] = 1;
 364
 365                 $objects = $this->select( $fields, $conditions, $options, $functionName );
 366
 367                 return ( !$objects || $objects->isEmpty() ) ? false : $objects->current();
 368         }
 369
 370         /**
 371          * Selects the the specified fields of the records matching the provided
 372          * conditions. Field names do NOT get prefixed.
 373          *
 374          * @since 1.20
 375          *
 376          * @param array $fields
 377          * @param array $conditions
 378          * @param array $options
 379          * @param string|null $functionName
 380          *
 381          * @return stdClass
 382          */
 383         public function rawSelectRow( array $fields, array $conditions = array(),
 384                 array $options = array(), $functionName = null
 385         ) {
 386                 $dbr = $this->getReadDbConnection();
 387
 388                 $result = $dbr->selectRow(
 389                         $this->getName(),
 390                         $fields,
 391                         $conditions,
 392                         is_null( $functionName ) ? __METHOD__ : $functionName,
 393                         $options
 394                 );
 395
 396                 $this->releaseConnection( $dbr );
 397
 398                 return $result;
 399         }
 400
 401         /**
 402          * Selects the the specified fields of the first record matching the provided
 403          * conditions and returns it as an associative array, or false when nothing matches.
 404          * This method makes use of selectFields and expects the same parameters and
 405          * returns the same results (if there are any, if there are none, this method returns false).
 406          * @see ORMTable::selectFields
 407          *
 408          * @since 1.20
 409          *
 410          * @param array|string|null $fields
 411          * @param array $conditions
 412          * @param array $options
 413          * @param bool $collapse Set to false to always return each result row as associative array.
 414          * @param string|null $functionName
 415          *
 416          * @return mixed|array|bool False on failure
 417          */
 418         public function selectFieldsRow( $fields = null, array $conditions = array(),
 419                 array $options = array(), $collapse = true, $functionName = null
 420         ) {
 421                 $options['LIMIT'] = 1;
 422
 423                 $objects = $this->selectFields( $fields, $conditions, $options, $collapse, $functionName );
 424
 425                 return empty( $objects ) ? false : $objects[0];
 426         }
 427
 428         /**
 429          * Returns if there is at least one record matching the provided conditions.
 430          * Condition field names get prefixed.
 431          *
 432          * @since 1.20
 433          *
 434          * @param array $conditions
 435          *
 436          * @return bool
 437          */
 438         public function has( array $conditions = array() ) {
 439                 return $this->selectRow( array( 'id' ), $conditions ) !== false;
 440         }
 441
 442         /**
 443          * Checks if the table exists
 444          *
 445          * @since 1.21
 446          *
 447          * @return bool
 448          */
 449         public function exists() {
 450                 $dbr = $this->getReadDbConnection();
 451                 $exists = $dbr->tableExists( $this->getName() );
 452                 $this->releaseConnection( $dbr );
 453
 454                 return $exists;
 455         }
 456
 457         /**
 458          * Returns the amount of matching records.
 459          * Condition field names get prefixed.
 460          *
 461          * Note that this can be expensive on large tables.
 462          * In such cases you might want to use DatabaseBase::estimateRowCount instead.
 463          *
 464          * @since 1.20
 465          *
 466          * @param array $conditions
 467          * @param array $options
 468          *
 469          * @return int
 470          */
 471         public function count( array $conditions = array(), array $options = array() ) {
 472                 $res = $this->rawSelectRow(
 473                         array( 'rowcount' => 'COUNT(*)' ),
 474                         $this->getPrefixedValues( $conditions ),
 475                         $options,
 476                         __METHOD__
 477                 );
 478
 479                 return $res->rowcount;
 480         }
 481
 482         /**
 483          * Removes the object from the database.
 484          *
 485          * @since 1.20
 486          *
 487          * @param array $conditions
 488          * @param string|null $functionName
 489          *
 490          * @return bool Success indicator
 491          */
 492         public function delete( array $conditions, $functionName = null ) {
 493                 $dbw = $this->getWriteDbConnection();
 494
 495                 $result = $dbw->delete(
 496                         $this->getName(),
 497                         $conditions === array() ? '*' : $this->getPrefixedValues( $conditions ),
 498                         is_null( $functionName ) ? __METHOD__ : $functionName
 499                 ) !== false; // DatabaseBase::delete does not always return true for success as documented...
 500
 501                 $this->releaseConnection( $dbw );
 502
 503                 return $result;
 504         }
 505
 506         /**
 507          * Get API parameters for the fields supported by this object.
 508          *
 509          * @since 1.20
 510          *
 511          * @param bool $requireParams
 512          * @param bool $setDefaults
 513          *
 514          * @return array
 515          */
 516         public function getAPIParams( $requireParams = false, $setDefaults = false ) {
 517                 $typeMap = array(
 518                         'id' => 'integer',
 519                         'int' => 'integer',
 520                         'float' => 'NULL',
 521                         'str' => 'string',
 522                         'bool' => 'integer',
 523                         'array' => 'string',
 524                         'blob' => 'string',
 525                 );
 526
 527                 $params = array();
 528                 $defaults = $this->getDefaults();
 529
 530                 foreach ( $this->getFields() as $field => $type ) {
 531                         if ( $field == 'id' ) {
 532                                 continue;
 533                         }
 534
 535                         $hasDefault = array_key_exists( $field, $defaults );
 536
 537                         $params[$field] = array(
 538                                 ApiBase::PARAM_TYPE => $typeMap[$type],
 539                                 ApiBase::PARAM_REQUIRED => $requireParams && !$hasDefault
 540                         );
 541
 542                         if ( $type == 'array' ) {
 543                                 $params[$field][ApiBase::PARAM_ISMULTI] = true;
 544                         }
 545
 546                         if ( $setDefaults && $hasDefault ) {
 547                                 $default = is_array( $defaults[$field] )
 548                                         ? implode( '|', $defaults[$field] )
 549                                         : $defaults[$field];
 550                                 $params[$field][ApiBase::PARAM_DFLT] = $default;
 551                         }
 552                 }
 553
 554                 return $params;
 555         }
 556
 557         /**
 558          * Returns an array with the fields and their descriptions.
 559          *
 560          * field name => field description
 561          *
 562          * @since 1.20
 563          *
 564          * @return array
 565          */
 566         public function getFieldDescriptions() {
 567                 return array();
 568         }
 569
 570         /**
 571          * Get the database ID used for read operations.
 572          *
 573          * @since 1.20
 574          *
 575          * @return int DB_ enum
 576          */
 577         public function getReadDb() {
 578                 return $this->readDb;
 579         }
 580
 581         /**
 582          * Set the database ID to use for read operations, use DB_XXX constants or
 583          *   an index to the load balancer setup.
 584          *
 585          * @param int $db
 586          *
 587          * @since 1.20
 588          */
 589         public function setReadDb( $db ) {
 590                 $this->readDb = $db;
 591         }
 592
 593         /**
 594          * Get the ID of the any foreign wiki to use as a target for database operations
 595          *
 596          * @since 1.20
 597          *
 598          * @return string|bool The target wiki, in a form that LBFactory understands
 599          *   (or false if the local wiki is used)
 600          */
 601         public function getTargetWiki() {
 602                 return $this->wiki;
 603         }
 604
 605         /**
 606          * Set the ID of the any foreign wiki to use as a target for database operations
 607          *
 608          * @param string|bool $wiki The target wiki, in a form that  LBFactory
 609          *   understands (or false if the local wiki shall be used)
 610          *
 611          * @since 1.20
 612          */
 613         public function setTargetWiki( $wiki ) {
 614                 $this->wiki = $wiki;
 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 getReadDbConnection() {
 628                 return $this->getConnection( $this->getReadDb(), array() );
 629         }
 630
 631         /**
 632          * Get the database type used for read operations.
 633          * This is to be used instead of wfGetDB.
 634          *
 635          * @see LoadBalancer::getConnection
 636          *
 637          * @since 1.20
 638          *
 639          * @return DatabaseBase The database object
 640          */
 641         public function getWriteDbConnection() {
 642                 return $this->getConnection( DB_MASTER, array() );
 643         }
 644
 645         /**
 646          * Releases the lease on the given database connection. This is useful mainly
 647          * for connections to a foreign wiki. It does nothing for connections to the local wiki.
 648          *
 649          * @see LoadBalancer::reuseConnection
 650          *
 651          * @param DatabaseBase $db
 652          *
 653          * @since 1.20
 654          */
 655         // @codingStandardsIgnoreStart Suppress "useless method overriding" sniffer warning
 656         public function releaseConnection( DatabaseBase $db ) {
 657                 parent::releaseConnection( $db ); // just make it public
 658         }
 659         // @codingStandardsIgnoreEnd
 660
 661         /**
 662          * Update the records matching the provided conditions by
 663          * setting the fields that are keys in the $values param to
 664          * their corresponding values.
 665          *
 666          * @since 1.20
 667          *
 668          * @param array $values
 669          * @param array $conditions
 670          *
 671          * @return bool Success indicator
 672          */
 673         public function update( array $values, array $conditions = array() ) {
 674                 $dbw = $this->getWriteDbConnection();
 675
 676                 $result = $dbw->update(
 677                         $this->getName(),
 678                         $this->getPrefixedValues( $values ),
 679                         $this->getPrefixedValues( $conditions ),
 680                         __METHOD__
 681                 ) !== false; // DatabaseBase::update does not always return true for success as documented...
 682
 683                 $this->releaseConnection( $dbw );
 684
 685                 return $result;
 686         }
 687
 688         /**
 689          * Computes the values of the summary fields of the objects matching the provided conditions.
 690          *
 691          * @since 1.20
 692          *
 693          * @param array|string|null $summaryFields
 694          * @param array $conditions
 695          */
 696         public function updateSummaryFields( $summaryFields = null, array $conditions = array() ) {
 697                 $slave = $this->getReadDb();
 698                 $this->setReadDb( DB_MASTER );
 699
 700                 /**
 701                  * @var IORMRow $item
 702                  */
 703                 foreach ( $this->select( null, $conditions ) as $item ) {
 704                         $item->loadSummaryFields( $summaryFields );
 705                         $item->setSummaryMode( true );
 706                         $item->save();
 707                 }
 708
 709                 $this->setReadDb( $slave );
 710         }
 711
 712         /**
 713          * Takes in an associative array with field names as keys and
 714          * their values as value. The field names are prefixed with the
 715          * db field prefix.
 716          *
 717          * @since 1.20
 718          *
 719          * @param array $values
 720          *
 721          * @return array
 722          */
 723         public function getPrefixedValues( array $values ) {
 724                 $prefixedValues = array();
 725
 726                 foreach ( $values as $field => $value ) {
 727                         if ( is_integer( $field ) ) {
 728                                 if ( is_array( $value ) ) {
 729                                         $field = $value[0];
 730                                         $value = $value[1];
 731                                 } else {
 732                                         $value = explode( ' ', $value, 2 );
 733                                         $value[0] = $this->getPrefixedField( $value[0] );
 734                                         $prefixedValues[] = implode( ' ', $value );
 735                                         continue;
 736                                 }
 737                         }
 738
 739                         $prefixedValues[$this->getPrefixedField( $field )] = $value;
 740                 }
 741
 742                 return $prefixedValues;
 743         }
 744
 745         /**
 746          * Takes in a field or array of fields and returns an
 747          * array with their prefixed versions, ready for db usage.
 748          *
 749          * @since 1.20
 750          *
 751          * @param array $fields
 752          *
 753          * @return array
 754          */
 755         public function getPrefixedFields( array $fields ) {
 756                 foreach ( $fields as &$field ) {
 757                         $field = $this->getPrefixedField( $field );
 758                 }
 759
 760                 return $fields;
 761         }
 762
 763         /**
 764          * Takes in a field and returns an it's prefixed version, ready for db usage.
 765          *
 766          * @since 1.20
 767          *
 768          * @param string|array $field
 769          *
 770          * @return string
 771          */
 772         public function getPrefixedField( $field ) {
 773                 return $this->getFieldPrefix() . $field;
 774         }
 775
 776         /**
 777          * Takes an array of field names with prefix and returns the unprefixed equivalent.
 778          *
 779          * @since 1.20
 780          *
 781          * @param array $fieldNames
 782          *
 783          * @return array
 784          */
 785         public function unprefixFieldNames( array $fieldNames ) {
 786                 return array_map( array( $this, 'unprefixFieldName' ), $fieldNames );
 787         }
 788
 789         /**
 790          * Takes a field name with prefix and returns the unprefixed equivalent.
 791          *
 792          * @since 1.20
 793          *
 794          * @param string $fieldName
 795          *
 796          * @return string
 797          */
 798         public function unprefixFieldName( $fieldName ) {
 799                 return substr( $fieldName, strlen( $this->getFieldPrefix() ) );
 800         }
 801
 802         /**
 803          * Get an instance of this class.
 804          *
 805          * @since 1.20
 806          * @deprecated since 1.21
 807          *
 808          * @return IORMTable
 809          */
 810         public static function singleton() {
 811                 $class = get_called_class();
 812
 813                 if ( !array_key_exists( $class, self::$instanceCache ) ) {
 814                         self::$instanceCache[$class] = new $class;
 815                 }
 816
 817                 return self::$instanceCache[$class];
 818         }
 819
 820         /**
 821          * Get an array with fields from a database result,
 822          * that can be fed directly to the constructor or
 823          * to setFields.
 824          *
 825          * @since 1.20
 826          *
 827          * @param stdClass $result
 828          * @throws MWException
 829          * @return array
 830          */
 831         public function getFieldsFromDBResult( stdClass $result ) {
 832                 $result = (array)$result;
 833
 834                 $rawFields = array_combine(
 835                         $this->unprefixFieldNames( array_keys( $result ) ),
 836                         array_values( $result )
 837                 );
 838
 839                 $fieldDefinitions = $this->getFields();
 840                 $fields = array();
 841
 842                 foreach ( $rawFields as $name => $value ) {
 843                         if ( array_key_exists( $name, $fieldDefinitions ) ) {
 844                                 switch ( $fieldDefinitions[$name] ) {
 845                                         case 'int':
 846                                                 $value = (int)$value;
 847                                                 break;
 848                                         case 'float':
 849                                                 $value = (float)$value;
 850                                                 break;
 851                                         case 'bool':
 852                                                 if ( is_string( $value ) ) {
 853                                                         $value = $value !== '0';
 854                                                 } elseif ( is_int( $value ) ) {
 855                                                         $value = $value !== 0;
 856                                                 }
 857                                                 break;
 858                                         case 'array':
 859                                                 if ( is_string( $value ) ) {
 860                                                         $value = unserialize( $value );
 861                                                 }
 862
 863                                                 if ( !is_array( $value ) ) {
 864                                                         $value = array();
 865                                                 }
 866                                                 break;
 867                                         case 'blob':
 868                                                 if ( is_string( $value ) ) {
 869                                                         $value = unserialize( $value );
 870                                                 }
 871                                                 break;
 872                                         case 'id':
 873                                                 if ( is_string( $value ) ) {
 874                                                         $value = (int)$value;
 875                                                 }
 876                                                 break;
 877                                 }
 878
 879                                 $fields[$name] = $value;
 880                         } else {
 881                                 throw new MWException( 'Attempted to set unknown field ' . $name );
 882                         }
 883                 }
 884
 885                 return $fields;
 886         }
 887
 888         /**
 889          * @see ORMTable::newRowFromFromDBResult
 890          *
 891          * @deprecated since 1.20 use newRowFromDBResult instead
 892          * @since 1.20
 893          *
 894          * @param stdClass $result
 895          *
 896          * @return IORMRow
 897          */
 898         public function newFromDBResult( stdClass $result ) {
 899                 return self::newRowFromDBResult( $result );
 900         }
 901
 902         /**
 903          * Get a new instance of the class from a database result.
 904          *
 905          * @since 1.20
 906          *
 907          * @param stdClass $result
 908          *
 909          * @return IORMRow
 910          */
 911         public function newRowFromDBResult( stdClass $result ) {
 912                 return $this->newRow( $this->getFieldsFromDBResult( $result ) );
 913         }
 914
 915         /**
 916          * @see ORMTable::newRow
 917          *
 918          * @deprecated since 1.20 use newRow instead
 919          * @since 1.20
 920          *
 921          * @param array $data
 922          * @param bool $loadDefaults
 923          *
 924          * @return IORMRow
 925          */
 926         public function newFromArray( array $data, $loadDefaults = false ) {
 927                 return static::newRow( $data, $loadDefaults );
 928         }
 929
 930         /**
 931          * Get a new instance of the class from an array.
 932          *
 933          * @since 1.20
 934          *
 935          * @param array $fields
 936          * @param bool $loadDefaults
 937          *
 938          * @return IORMRow
 939          */
 940         public function newRow( array $fields, $loadDefaults = false ) {
 941                 $class = $this->getRowClass();
 942
 943                 return new $class( $this, $fields, $loadDefaults );
 944         }
 945
 946         /**
 947          * Return the names of the fields.
 948          *
 949          * @since 1.20
 950          *
 951          * @return array
 952          */
 953         public function getFieldNames() {
 954                 return array_keys( $this->getFields() );
 955         }
 956
 957         /**
 958          * Gets if the object can take a certain field.
 959          *
 960          * @since 1.20
 961          *
 962          * @param string $name
 963          *
 964          * @return bool
 965          */
 966         public function canHaveField( $name ) {
 967                 return array_key_exists( $name, $this->getFields() );
 968         }
 969
 970         /**
 971          * Updates the provided row in the database.
 972          *
 973          * @since 1.22
 974          *
 975          * @param IORMRow $row The row to save
 976          * @param string|null $functionName
 977          *
 978          * @return bool Success indicator
 979          */
 980         public function updateRow( IORMRow $row, $functionName = null ) {
 981                 $dbw = $this->getWriteDbConnection();
 982
 983                 $success = $dbw->update(
 984                         $this->getName(),
 985                         $this->getWriteValues( $row ),
 986                         $this->getPrefixedValues( array( 'id' => $row->getId() ) ),
 987                         is_null( $functionName ) ? __METHOD__ : $functionName
 988                 );
 989
 990                 $this->releaseConnection( $dbw );
 991
 992                 // DatabaseBase::update does not always return true for success as documented...
 993                 return $success !== false;
 994         }
 995
 996         /**
 997          * Inserts the provided row into the database.
 998          *
 999          * @since 1.22
1000          *
1001          * @param IORMRow $row
1002          * @param string|null $functionName
1003          * @param array|null $options
1004          *
1005          * @return bool Success indicator
1006          */
1007         public function insertRow( IORMRow $row, $functionName = null, array $options = null ) {
1008                 $dbw = $this->getWriteDbConnection();
1009
1010                 $success = $dbw->insert(
1011                         $this->getName(),
1012                         $this->getWriteValues( $row ),
1013                         is_null( $functionName ) ? __METHOD__ : $functionName,
1014                         $options
1015                 );
1016
1017                 // DatabaseBase::insert does not always return true for success as documented...
1018                 $success = $success !== false;
1019
1020                 if ( $success ) {
1021                         $row->setField( 'id', $dbw->insertId() );
1022                 }
1023
1024                 $this->releaseConnection( $dbw );
1025
1026                 return $success;
1027         }
1028
1029         /**
1030          * Gets the fields => values to write to the table.
1031          *
1032          * @since 1.22
1033          *
1034          * @param IORMRow $row
1035          *
1036          * @return array
1037          */
1038         protected function getWriteValues( IORMRow $row ) {
1039                 $values = array();
1040
1041                 $rowFields = $row->getFields();
1042
1043                 foreach ( $this->getFields() as $name => $type ) {
1044                         if ( array_key_exists( $name, $rowFields ) ) {
1045                                 $value = $rowFields[$name];
1046
1047                                 switch ( $type ) {
1048                                         case 'array':
1049                                                 $value = (array)$value;
1050                                         // fall-through!
1051                                         case 'blob':
1052                                                 $value = serialize( $value );
1053                                         // fall-through!
1054                                 }
1055
1056                                 $values[$this->getPrefixedField( $name )] = $value;
1057                         }
1058                 }
1059
1060                 return $values;
1061         }
1062
1063         /**
1064          * Removes the provided row from the database.
1065          *
1066          * @since 1.22
1067          *
1068          * @param IORMRow $row
1069          * @param string|null $functionName
1070          *
1071          * @return bool Success indicator
1072          */
1073         public function removeRow( IORMRow $row, $functionName = null ) {
1074                 $success = $this->delete(
1075                         array( 'id' => $row->getId() ),
1076                         is_null( $functionName ) ? __METHOD__ : $functionName
1077                 );
1078
1079                 // DatabaseBase::delete does not always return true for success as documented...
1080                 return $success !== false;
1081         }
1082
1083         /**
1084          * Add an amount (can be negative) to the specified field (needs to be numeric).
1085          *
1086          * @since 1.22
1087          *
1088          * @param array $conditions
1089          * @param string $field
1090          * @param int $amount
1091          *
1092          * @return bool Success indicator
1093          * @throws MWException
1094          */
1095         public function addToField( array $conditions, $field, $amount ) {
1096                 if ( !array_key_exists( $field, $this->fields ) ) {
1097                         throw new MWException( 'Unknown field "' . $field . '" provided' );
1098                 }
1099
1100                 if ( $amount == 0 ) {
1101                         return true;
1102                 }
1103
1104                 $absoluteAmount = abs( $amount );
1105                 $isNegative = $amount < 0;
1106
1107                 $fullField = $this->getPrefixedField( $field );
1108
1109                 $dbw = $this->getWriteDbConnection();
1110
1111                 $success = $dbw->update(
1112                         $this->getName(),
1113                         array( "$fullField=$fullField" . ( $isNegative ? '-' : '+' ) . $absoluteAmount ),
1114                         $this->getPrefixedValues( $conditions ),
1115                         __METHOD__
1116                 ) !== false; // DatabaseBase::update does not always return true for success as documented...
1117
1118                 $this->releaseConnection( $dbw );
1119
1120                 return $success;
1121         }
1122 }