includes/db/DatabaseOracle.php

   1 <?php
   2 /**
   3  * This is the Oracle database abstraction layer.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Database
  22  */
  23
  24 use Wikimedia\Timestamp\ConvertibleTimestamp;
  25 use Wikimedia\Rdbms\Database;
  26 use Wikimedia\Rdbms\DatabaseDomain;
  27 use Wikimedia\Rdbms\Blob;
  28 use Wikimedia\Rdbms\ResultWrapper;
  29 use Wikimedia\Rdbms\DBConnectionError;
  30 use Wikimedia\Rdbms\DBUnexpectedError;
  31 use Wikimedia\Rdbms\DBExpectedError;
  32
  33 /**
  34  * @ingroup Database
  35  */
  36 class DatabaseOracle extends Database {
  37         /** @var resource */
  38         protected $mLastResult = null;
  39
  40         /** @var int The number of rows affected as an integer */
  41         protected $mAffectedRows;
  42
  43         /** @var bool */
  44         private $ignoreDupValOnIndex = false;
  45
  46         /** @var bool|array */
  47         private $sequenceData = null;
  48
  49         /** @var string Character set for Oracle database */
  50         private $defaultCharset = 'AL32UTF8';
  51
  52         /** @var array */
  53         private $mFieldInfoCache = [];
  54
  55         /** @var string[] Map of (reserved table name => alternate table name) */
  56         private $keywordTableMap = [];
  57
  58         /**
  59          * @see Database::__construct()
  60          * @param array $params Additional parameters include:
  61          *   - keywordTableMap : Map of reserved table names to alternative table names to use
  62          */
  63         function __construct( array $params ) {
  64                 $this->keywordTableMap = $params['keywordTableMap'] ?? [];
  65                 $params['tablePrefix'] = strtoupper( $params['tablePrefix'] );
  66                 parent::__construct( $params );
  67                 Hooks::run( 'DatabaseOraclePostInit', [ $this ] );
  68         }
  69
  70         function __destruct() {
  71                 if ( $this->opened ) {
  72                         Wikimedia\suppressWarnings();
  73                         $this->close();
  74                         Wikimedia\restoreWarnings();
  75                 }
  76         }
  77
  78         function getType() {
  79                 return 'oracle';
  80         }
  81
  82         function implicitGroupby() {
  83                 return false;
  84         }
  85
  86         function implicitOrderby() {
  87                 return false;
  88         }
  89
  90         protected function open( $server, $user, $password, $dbName, $schema, $tablePrefix ) {
  91                 if ( !function_exists( 'oci_connect' ) ) {
  92                         throw new DBConnectionError(
  93                                 $this,
  94                                 "Oracle functions missing, have you compiled PHP with the --with-oci8 option?\n " .
  95                                         "(Note: if you recently installed PHP, you may need to restart your webserver\n " .
  96                                         "and database)\n" );
  97                 }
  98
  99                 $this->close();
 100                 $this->user = $user;
 101                 $this->password = $password;
 102                 if ( !$server ) {
 103                         // Backward compatibility (server used to be null and TNS was supplied in dbname)
 104                         $this->server = $dbName;
 105                         $realDatabase = $user;
 106                 } else {
 107                         // $server now holds the TNS endpoint
 108                         $this->server = $server;
 109                         // $dbName is schema name if different from username
 110                         $realDatabase = $dbName ?: $user;
 111                 }
 112
 113                 if ( !strlen( $user ) ) { # e.g. the class is being loaded
 114                         return null;
 115                 }
 116
 117                 $session_mode = ( $this->flags & DBO_SYSDBA ) ? OCI_SYSDBA : OCI_DEFAULT;
 118
 119                 Wikimedia\suppressWarnings();
 120                 if ( $this->flags & DBO_PERSISTENT ) {
 121                         $this->conn = oci_pconnect(
 122                                 $this->user,
 123                                 $this->password,
 124                                 $this->server,
 125                                 $this->defaultCharset,
 126                                 $session_mode
 127                         );
 128                 } elseif ( $this->flags & DBO_DEFAULT ) {
 129                         $this->conn = oci_new_connect(
 130                                 $this->user,
 131                                 $this->password,
 132                                 $this->server,
 133                                 $this->defaultCharset,
 134                                 $session_mode
 135                         );
 136                 } else {
 137                         $this->conn = oci_connect(
 138                                 $this->user,
 139                                 $this->password,
 140                                 $this->server,
 141                                 $this->defaultCharset,
 142                                 $session_mode
 143                         );
 144                 }
 145                 Wikimedia\restoreWarnings();
 146
 147                 if ( $this->user != $realDatabase ) {
 148                         // change current schema in session
 149                         $this->selectDB( $realDatabase );
 150                 } else {
 151                         $this->currentDomain = new DatabaseDomain(
 152                                 $realDatabase,
 153                                 null,
 154                                 $tablePrefix
 155                         );
 156                 }
 157
 158                 if ( !$this->conn ) {
 159                         throw new DBConnectionError( $this, $this->lastError() );
 160                 }
 161
 162                 $this->opened = true;
 163
 164                 # removed putenv calls because they interfere with the system globaly
 165                 $this->doQuery( 'ALTER SESSION SET NLS_TIMESTAMP_FORMAT=\'DD-MM-YYYY HH24:MI:SS.FF6\'' );
 166                 $this->doQuery( 'ALTER SESSION SET NLS_TIMESTAMP_TZ_FORMAT=\'DD-MM-YYYY HH24:MI:SS.FF6\'' );
 167                 $this->doQuery( 'ALTER SESSION SET NLS_NUMERIC_CHARACTERS=\'.,\'' );
 168
 169                 return (bool)$this->conn;
 170         }
 171
 172         /**
 173          * Closes a database connection, if it is open
 174          * Returns success, true if already closed
 175          * @return bool
 176          */
 177         protected function closeConnection() {
 178                 return oci_close( $this->conn );
 179         }
 180
 181         function execFlags() {
 182                 return $this->trxLevel ? OCI_NO_AUTO_COMMIT : OCI_COMMIT_ON_SUCCESS;
 183         }
 184
 185         /**
 186          * @param string $sql
 187          * @return bool|mixed|ORAResult
 188          */
 189         protected function doQuery( $sql ) {
 190                 if ( !mb_check_encoding( (string)$sql, 'UTF-8' ) ) {
 191                         throw new DBUnexpectedError( $this, "SQL encoding is invalid\n$sql" );
 192                 }
 193
 194                 // handle some oracle specifics
 195                 // remove AS column/table/subquery namings
 196                 if ( !$this->getFlag( DBO_DDLMODE ) ) {
 197                         $sql = preg_replace( '/ as /i', ' ', $sql );
 198                 }
 199
 200                 // Oracle has issues with UNION clause if the statement includes LOB fields
 201                 // So we do a UNION ALL and then filter the results array with array_unique
 202                 $union_unique = ( preg_match( '/\/\* UNION_UNIQUE \*\/ /', $sql ) != 0 );
 203                 // EXPLAIN syntax in Oracle is EXPLAIN PLAN FOR and it return nothing
 204                 // you have to select data from plan table after explain
 205                 $explain_id = MWTimestamp::getLocalInstance()->format( 'dmYHis' );
 206
 207                 $sql = preg_replace(
 208                         '/^EXPLAIN /',
 209                         'EXPLAIN PLAN SET STATEMENT_ID = \'' . $explain_id . '\' FOR',
 210                         $sql,
 211                         1,
 212                         $explain_count
 213                 );
 214
 215                 Wikimedia\suppressWarnings();
 216
 217                 $this->mLastResult = $stmt = oci_parse( $this->conn, $sql );
 218                 if ( $stmt === false ) {
 219                         $e = oci_error( $this->conn );
 220                         $this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
 221
 222                         return false;
 223                 }
 224
 225                 if ( !oci_execute( $stmt, $this->execFlags() ) ) {
 226                         $e = oci_error( $stmt );
 227                         if ( !$this->ignoreDupValOnIndex || $e['code'] != '1' ) {
 228                                 $this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
 229
 230                                 return false;
 231                         }
 232                 }
 233
 234                 Wikimedia\restoreWarnings();
 235
 236                 if ( $explain_count > 0 ) {
 237                         return $this->doQuery( 'SELECT id, cardinality "ROWS" FROM plan_table ' .
 238                                 'WHERE statement_id = \'' . $explain_id . '\'' );
 239                 } elseif ( oci_statement_type( $stmt ) == 'SELECT' ) {
 240                         return new ORAResult( $this, $stmt, $union_unique );
 241                 } else {
 242                         $this->mAffectedRows = oci_num_rows( $stmt );
 243
 244                         return true;
 245                 }
 246         }
 247
 248         function queryIgnore( $sql, $fname = '' ) {
 249                 return $this->query( $sql, $fname, true );
 250         }
 251
 252         /**
 253          * Frees resources associated with the LOB descriptor
 254          * @param ResultWrapper|ORAResult $res
 255          */
 256         function freeResult( $res ) {
 257                 if ( $res instanceof ResultWrapper ) {
 258                         $res = $res->result;
 259                 }
 260
 261                 $res->free();
 262         }
 263
 264         /**
 265          * @param ResultWrapper|ORAResult $res
 266          * @return mixed
 267          */
 268         function fetchObject( $res ) {
 269                 if ( $res instanceof ResultWrapper ) {
 270                         $res = $res->result;
 271                 }
 272
 273                 return $res->fetchObject();
 274         }
 275
 276         /**
 277          * @param ResultWrapper|ORAResult $res
 278          * @return mixed
 279          */
 280         function fetchRow( $res ) {
 281                 if ( $res instanceof ResultWrapper ) {
 282                         $res = $res->result;
 283                 }
 284
 285                 return $res->fetchRow();
 286         }
 287
 288         /**
 289          * @param ResultWrapper|ORAResult $res
 290          * @return int
 291          */
 292         function numRows( $res ) {
 293                 if ( $res instanceof ResultWrapper ) {
 294                         $res = $res->result;
 295                 }
 296
 297                 return $res->numRows();
 298         }
 299
 300         /**
 301          * @param ResultWrapper|ORAResult $res
 302          * @return int
 303          */
 304         function numFields( $res ) {
 305                 if ( $res instanceof ResultWrapper ) {
 306                         $res = $res->result;
 307                 }
 308
 309                 return $res->numFields();
 310         }
 311
 312         function fieldName( $stmt, $n ) {
 313                 return oci_field_name( $stmt, $n );
 314         }
 315
 316         function insertId() {
 317                 $res = $this->query( "SELECT lastval_pkg.getLastval FROM dual" );
 318                 $row = $this->fetchRow( $res );
 319                 return is_null( $row[0] ) ? null : (int)$row[0];
 320         }
 321
 322         /**
 323          * @param mixed $res
 324          * @param int $row
 325          */
 326         function dataSeek( $res, $row ) {
 327                 if ( $res instanceof ORAResult ) {
 328                         $res->seek( $row );
 329                 } else {
 330                         $res->result->seek( $row );
 331                 }
 332         }
 333
 334         function lastError() {
 335                 if ( $this->conn === false ) {
 336                         $e = oci_error();
 337                 } else {
 338                         $e = oci_error( $this->conn );
 339                 }
 340
 341                 return $e['message'];
 342         }
 343
 344         function lastErrno() {
 345                 if ( $this->conn === false ) {
 346                         $e = oci_error();
 347                 } else {
 348                         $e = oci_error( $this->conn );
 349                 }
 350
 351                 return $e['code'];
 352         }
 353
 354         protected function fetchAffectedRowCount() {
 355                 return $this->mAffectedRows;
 356         }
 357
 358         /**
 359          * Returns information about an index
 360          * If errors are explicitly ignored, returns NULL on failure
 361          * @param string $table
 362          * @param string $index
 363          * @param string $fname
 364          * @return bool
 365          */
 366         function indexInfo( $table, $index, $fname = __METHOD__ ) {
 367                 return false;
 368         }
 369
 370         function indexUnique( $table, $index, $fname = __METHOD__ ) {
 371                 return false;
 372         }
 373
 374         function insert( $table, $a, $fname = __METHOD__, $options = [] ) {
 375                 if ( !count( $a ) ) {
 376                         return true;
 377                 }
 378
 379                 if ( !is_array( $options ) ) {
 380                         $options = [ $options ];
 381                 }
 382
 383                 if ( in_array( 'IGNORE', $options ) ) {
 384                         $this->ignoreDupValOnIndex = true;
 385                 }
 386
 387                 if ( !is_array( reset( $a ) ) ) {
 388                         $a = [ $a ];
 389                 }
 390
 391                 foreach ( $a as &$row ) {
 392                         $this->insertOneRow( $table, $row, $fname );
 393                 }
 394
 395                 if ( in_array( 'IGNORE', $options ) ) {
 396                         $this->ignoreDupValOnIndex = false;
 397                 }
 398
 399                 return true;
 400         }
 401
 402         private function fieldBindStatement( $table, $col, &$val, $includeCol = false ) {
 403                 $col_info = $this->fieldInfoMulti( $table, $col );
 404                 $col_type = $col_info != false ? $col_info->type() : 'CONSTANT';
 405
 406                 $bind = '';
 407                 if ( is_numeric( $col ) ) {
 408                         $bind = $val;
 409                         $val = null;
 410
 411                         return $bind;
 412                 } elseif ( $includeCol ) {
 413                         $bind = "$col = ";
 414                 }
 415
 416                 if ( $val == '' && $val !== 0 && $col_type != 'BLOB' && $col_type != 'CLOB' ) {
 417                         $val = null;
 418                 }
 419
 420                 if ( $val === 'NULL' ) {
 421                         $val = null;
 422                 }
 423
 424                 if ( $val === null ) {
 425                         if (
 426                                 $col_info != false &&
 427                                 $col_info->isNullable() == 0 &&
 428                                 $col_info->defaultValue() != null
 429                         ) {
 430                                 $bind .= 'DEFAULT';
 431                         } else {
 432                                 $bind .= 'NULL';
 433                         }
 434                 } else {
 435                         $bind .= ':' . $col;
 436                 }
 437
 438                 return $bind;
 439         }
 440
 441         /**
 442          * @param string $table
 443          * @param array $row
 444          * @param string $fname
 445          * @return bool
 446          * @throws DBUnexpectedError
 447          */
 448         private function insertOneRow( $table, $row, $fname ) {
 449                 $table = $this->tableName( $table );
 450                 // "INSERT INTO tables (a, b, c)"
 451                 $sql = "INSERT INTO " . $table . " (" . implode( ',', array_keys( $row ) ) . ')';
 452                 $sql .= " VALUES (";
 453
 454                 // for each value, append ":key"
 455                 $first = true;
 456                 foreach ( $row as $col => &$val ) {
 457                         if ( !$first ) {
 458                                 $sql .= ', ';
 459                         } else {
 460                                 $first = false;
 461                         }
 462                         if ( $this->isQuotedIdentifier( $val ) ) {
 463                                 $sql .= $this->removeIdentifierQuotes( $val );
 464                                 unset( $row[$col] );
 465                         } else {
 466                                 $sql .= $this->fieldBindStatement( $table, $col, $val );
 467                         }
 468                 }
 469                 $sql .= ')';
 470
 471                 $this->mLastResult = $stmt = oci_parse( $this->conn, $sql );
 472                 if ( $stmt === false ) {
 473                         $e = oci_error( $this->conn );
 474                         $this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
 475
 476                         return false;
 477                 }
 478                 foreach ( $row as $col => &$val ) {
 479                         $col_info = $this->fieldInfoMulti( $table, $col );
 480                         $col_type = $col_info != false ? $col_info->type() : 'CONSTANT';
 481
 482                         if ( $val === null ) {
 483                                 // do nothing ... null was inserted in statement creation
 484                         } elseif ( $col_type != 'BLOB' && $col_type != 'CLOB' ) {
 485                                 if ( is_object( $val ) ) {
 486                                         $val = $val->fetch();
 487                                 }
 488
 489                                 // backward compatibility
 490                                 if (
 491                                         preg_match( '/^timestamp.*/i', $col_type ) == 1 &&
 492                                         strtolower( $val ) == 'infinity'
 493                                 ) {
 494                                         $val = $this->getInfinity();
 495                                 }
 496
 497                                 $val = $this->getVerifiedUTF8( $val );
 498                                 if ( oci_bind_by_name( $stmt, ":$col", $val, -1, SQLT_CHR ) === false ) {
 499                                         $e = oci_error( $stmt );
 500                                         $this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
 501
 502                                         return false;
 503                                 }
 504                         } else {
 505                                 /** @var OCI_Lob[] $lob */
 506                                 $lob[$col] = oci_new_descriptor( $this->conn, OCI_D_LOB );
 507                                 if ( $lob[$col] === false ) {
 508                                         $e = oci_error( $stmt );
 509                                         throw new DBUnexpectedError(
 510                                                 $this,
 511                                                 "Cannot create LOB descriptor: " . $e['message']
 512                                         );
 513                                 }
 514
 515                                 if ( is_object( $val ) ) {
 516                                         $val = $val->fetch();
 517                                 }
 518
 519                                 if ( $col_type == 'BLOB' ) {
 520                                         $lob[$col]->writeTemporary( $val, OCI_TEMP_BLOB );
 521                                         oci_bind_by_name( $stmt, ":$col", $lob[$col], -1, OCI_B_BLOB );
 522                                 } else {
 523                                         $lob[$col]->writeTemporary( $val, OCI_TEMP_CLOB );
 524                                         oci_bind_by_name( $stmt, ":$col", $lob[$col], -1, OCI_B_CLOB );
 525                                 }
 526                         }
 527                 }
 528
 529                 Wikimedia\suppressWarnings();
 530
 531                 if ( oci_execute( $stmt, $this->execFlags() ) === false ) {
 532                         $e = oci_error( $stmt );
 533                         if ( !$this->ignoreDupValOnIndex || $e['code'] != '1' ) {
 534                                 $this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
 535
 536                                 return false;
 537                         } else {
 538                                 $this->mAffectedRows = oci_num_rows( $stmt );
 539                         }
 540                 } else {
 541                         $this->mAffectedRows = oci_num_rows( $stmt );
 542                 }
 543
 544                 Wikimedia\restoreWarnings();
 545
 546                 if ( isset( $lob ) ) {
 547                         foreach ( $lob as $lob_v ) {
 548                                 $lob_v->free();
 549                         }
 550                 }
 551
 552                 if ( !$this->trxLevel ) {
 553                         oci_commit( $this->conn );
 554                 }
 555
 556                 return oci_free_statement( $stmt );
 557         }
 558
 559         function nativeInsertSelect( $destTable, $srcTable, $varMap, $conds, $fname = __METHOD__,
 560                 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
 561         ) {
 562                 $destTable = $this->tableName( $destTable );
 563
 564                 $sequenceData = $this->getSequenceData( $destTable );
 565                 if ( $sequenceData !== false &&
 566                         !isset( $varMap[$sequenceData['column']] )
 567                 ) {
 568                         $varMap[$sequenceData['column']] =
 569                                 'GET_SEQUENCE_VALUE(\'' . $sequenceData['sequence'] . '\')';
 570                 }
 571
 572                 // count-alias subselect fields to avoid abigious definition errors
 573                 $i = 0;
 574                 foreach ( $varMap as &$val ) {
 575                         $val .= ' field' . $i;
 576                         $i++;
 577                 }
 578
 579                 $selectSql = $this->selectSQLText(
 580                         $srcTable,
 581                         array_values( $varMap ),
 582                         $conds,
 583                         $fname,
 584                         $selectOptions,
 585                         $selectJoinConds
 586                 );
 587
 588                 $sql = "INSERT INTO $destTable (" .
 589                         implode( ',', array_keys( $varMap ) ) . ') ' . $selectSql;
 590
 591                 if ( in_array( 'IGNORE', $insertOptions ) ) {
 592                         $this->ignoreDupValOnIndex = true;
 593                 }
 594
 595                 $this->query( $sql, $fname );
 596
 597                 if ( in_array( 'IGNORE', $insertOptions ) ) {
 598                         $this->ignoreDupValOnIndex = false;
 599                 }
 600         }
 601
 602         public function upsert( $table, array $rows, $uniqueIndexes, array $set,
 603                 $fname = __METHOD__
 604         ) {
 605                 if ( $rows === [] ) {
 606                         return true; // nothing to do
 607                 }
 608
 609                 if ( !is_array( reset( $rows ) ) ) {
 610                         $rows = [ $rows ];
 611                 }
 612
 613                 $sequenceData = $this->getSequenceData( $table );
 614                 if ( $sequenceData !== false ) {
 615                         // add sequence column to each list of columns, when not set
 616                         foreach ( $rows as &$row ) {
 617                                 if ( !isset( $row[$sequenceData['column']] ) ) {
 618                                         $row[$sequenceData['column']] =
 619                                                 $this->addIdentifierQuotes( 'GET_SEQUENCE_VALUE(\'' .
 620                                                         $sequenceData['sequence'] . '\')' );
 621                                 }
 622                         }
 623                 }
 624
 625                 return parent::upsert( $table, $rows, $uniqueIndexes, $set, $fname );
 626         }
 627
 628         public function tableName( $name, $format = 'quoted' ) {
 629                 // Replace reserved words with better ones
 630                 $name = $this->remappedTableName( $name );
 631
 632                 return strtoupper( parent::tableName( $name, $format ) );
 633         }
 634
 635         /**
 636          * @param string $name
 637          * @return string Value of $name or remapped name if $name is a reserved keyword
 638          */
 639         public function remappedTableName( $name ) {
 640                 return $this->keywordTableMap[$name] ?? $name;
 641         }
 642
 643         function tableNameInternal( $name ) {
 644                 $name = $this->tableName( $name );
 645
 646                 return preg_replace( '/.*\.(.*)/', '$1', $name );
 647         }
 648
 649         /**
 650          * Return sequence_name if table has a sequence
 651          *
 652          * @param string $table
 653          * @return bool
 654          */
 655         private function getSequenceData( $table ) {
 656                 if ( $this->sequenceData == null ) {
 657                         $dbname = $this->currentDomain->getDatabase();
 658                         $prefix = $this->currentDomain->getTablePrefix();
 659                         // See https://docs.oracle.com/cd/B19306_01/server.102/b14200/functions040.htm
 660                         $decodeArgs = [ 'atc.table_name' ]; // the switch
 661                         foreach ( $this->keywordTableMap as $reserved => $alternative ) {
 662                                 $search = strtoupper( $prefix . $alternative ); // case
 663                                 $replace = strtoupper( $prefix . $reserved ); // result
 664                                 $decodeArgs[] = $this->addQuotes( $search );
 665                                 $decodeArgs[] = $this->addQuotes( $replace );
 666                         }
 667                         $decodeArgs[] = [ 'atc.table_name' ]; // default
 668                         $decodeArgs = implode( ', ', $decodeArgs );
 669
 670                         $result = $this->doQuery(
 671                                 "SELECT lower(asq.sequence_name), lower(atc.table_name), lower(atc.column_name)
 672                                 FROM all_sequences asq, all_tab_columns atc
 673                                 WHERE decode({$decodeArgs}) || '_' ||
 674                                 atc.column_name || '_SEQ' = '{$prefix}' || asq.sequence_name
 675                                 AND asq.sequence_owner = upper('{$dbname}')
 676                                 AND atc.owner = upper('{$dbname}')"
 677                         );
 678
 679                         while ( ( $row = $result->fetchRow() ) !== false ) {
 680                                 $this->sequenceData[$row[1]] = [
 681                                         'sequence' => $row[0],
 682                                         'column' => $row[2]
 683                                 ];
 684                         }
 685                 }
 686                 $table = strtolower( $this->removeIdentifierQuotes( $this->tableName( $table ) ) );
 687
 688                 return $this->sequenceData[$table] ?? false;
 689         }
 690
 691         /**
 692          * Returns the size of a text field, or -1 for "unlimited"
 693          *
 694          * @param string $table
 695          * @param string $field
 696          * @return mixed
 697          */
 698         function textFieldSize( $table, $field ) {
 699                 $fieldInfoData = $this->fieldInfo( $table, $field );
 700
 701                 return $fieldInfoData->maxLength();
 702         }
 703
 704         function limitResult( $sql, $limit, $offset = false ) {
 705                 if ( $offset === false ) {
 706                         $offset = 0;
 707                 }
 708
 709                 return "SELECT * FROM ($sql) WHERE rownum >= (1 + $offset) AND rownum < (1 + $limit + $offset)";
 710         }
 711
 712         function encodeBlob( $b ) {
 713                 return new Blob( $b );
 714         }
 715
 716         function unionQueries( $sqls, $all ) {
 717                 $glue = ' UNION ALL ';
 718
 719                 return 'SELECT * ' . ( $all ? '' : '/* UNION_UNIQUE */ ' ) .
 720                         'FROM (' . implode( $glue, $sqls ) . ')';
 721         }
 722
 723         function wasDeadlock() {
 724                 return $this->lastErrno() == 'OCI-00060';
 725         }
 726
 727         function duplicateTableStructure( $oldName, $newName, $temporary = false,
 728                 $fname = __METHOD__
 729         ) {
 730                 $temporary = $temporary ? 'TRUE' : 'FALSE';
 731                 $tablePrefix = $this->currentDomain->getTablePrefix();
 732
 733                 $newName = strtoupper( $newName );
 734                 $oldName = strtoupper( $oldName );
 735
 736                 $tabName = substr( $newName, strlen( $tablePrefix ) );
 737                 $oldPrefix = substr( $oldName, 0, strlen( $oldName ) - strlen( $tabName ) );
 738                 $newPrefix = strtoupper( $tablePrefix );
 739
 740                 return $this->doQuery( "BEGIN DUPLICATE_TABLE( '$tabName', " .
 741                         "'$oldPrefix', '$newPrefix', $temporary ); END;" );
 742         }
 743
 744         function listTables( $prefix = null, $fname = __METHOD__ ) {
 745                 $listWhere = '';
 746                 if ( !empty( $prefix ) ) {
 747                         $listWhere = ' AND table_name LIKE \'' . strtoupper( $prefix ) . '%\'';
 748                 }
 749
 750                 $owner = strtoupper( $this->getDBname() );
 751                 $result = $this->doQuery( "SELECT table_name FROM all_tables " .
 752                         "WHERE owner='$owner' AND table_name NOT LIKE '%!_IDX\$_' ESCAPE '!' $listWhere" );
 753
 754                 // dirty code ... i know
 755                 $endArray = [];
 756                 $endArray[] = strtoupper( $prefix . 'MWUSER' );
 757                 $endArray[] = strtoupper( $prefix . 'PAGE' );
 758                 $endArray[] = strtoupper( $prefix . 'IMAGE' );
 759                 $fixedOrderTabs = $endArray;
 760                 while ( ( $row = $result->fetchRow() ) !== false ) {
 761                         if ( !in_array( $row['table_name'], $fixedOrderTabs ) ) {
 762                                 $endArray[] = $row['table_name'];
 763                         }
 764                 }
 765
 766                 return $endArray;
 767         }
 768
 769         public function dropTable( $tableName, $fName = __METHOD__ ) {
 770                 $tableName = $this->tableName( $tableName );
 771                 if ( !$this->tableExists( $tableName ) ) {
 772                         return false;
 773                 }
 774
 775                 return $this->doQuery( "DROP TABLE $tableName CASCADE CONSTRAINTS PURGE" );
 776         }
 777
 778         public function timestamp( $ts = 0 ) {
 779                 $t = new ConvertibleTimestamp( $ts );
 780                 // Let errors bubble up to avoid putting garbage in the DB
 781                 return $t->getTimestamp( TS_ORACLE );
 782         }
 783
 784         /**
 785          * Return aggregated value function call
 786          *
 787          * @param array $valuedata
 788          * @param string $valuename
 789          * @return mixed
 790          */
 791         public function aggregateValue( $valuedata, $valuename = 'value' ) {
 792                 return $valuedata;
 793         }
 794
 795         /**
 796          * @return string Wikitext of a link to the server software's web site
 797          */
 798         public function getSoftwareLink() {
 799                 return '[{{int:version-db-oracle-url}} Oracle]';
 800         }
 801
 802         /**
 803          * @return string Version information from the database
 804          */
 805         function getServerVersion() {
 806                 // better version number, fallback on driver
 807                 $rset = $this->doQuery(
 808                         'SELECT version FROM product_component_version ' .
 809                                 'WHERE UPPER(product) LIKE \'ORACLE DATABASE%\''
 810                 );
 811                 $row = $rset->fetchRow();
 812                 if ( !$row ) {
 813                         return oci_server_version( $this->conn );
 814                 }
 815
 816                 return $row['version'];
 817         }
 818
 819         /**
 820          * Query whether a given index exists
 821          * @param string $table
 822          * @param string $index
 823          * @param string $fname
 824          * @return bool
 825          */
 826         function indexExists( $table, $index, $fname = __METHOD__ ) {
 827                 $table = $this->tableName( $table );
 828                 $table = strtoupper( $this->removeIdentifierQuotes( $table ) );
 829                 $index = strtoupper( $index );
 830                 $owner = strtoupper( $this->getDBname() );
 831                 $sql = "SELECT 1 FROM all_indexes WHERE owner='$owner' AND index_name='{$table}_{$index}'";
 832                 $res = $this->doQuery( $sql );
 833                 if ( $res ) {
 834                         $count = $res->numRows();
 835                         $res->free();
 836                 } else {
 837                         $count = 0;
 838                 }
 839
 840                 return $count != 0;
 841         }
 842
 843         /**
 844          * Query whether a given table exists (in the given schema, or the default mw one if not given)
 845          * @param string $table
 846          * @param string $fname
 847          * @return bool
 848          */
 849         function tableExists( $table, $fname = __METHOD__ ) {
 850                 $table = $this->tableName( $table );
 851                 $table = $this->addQuotes( strtoupper( $this->removeIdentifierQuotes( $table ) ) );
 852                 $owner = $this->addQuotes( strtoupper( $this->getDBname() ) );
 853                 $sql = "SELECT 1 FROM all_tables WHERE owner=$owner AND table_name=$table";
 854                 $res = $this->doQuery( $sql );
 855                 if ( $res && $res->numRows() > 0 ) {
 856                         $exists = true;
 857                 } else {
 858                         $exists = false;
 859                 }
 860
 861                 $res->free();
 862
 863                 return $exists;
 864         }
 865
 866         /**
 867          * Function translates mysql_fetch_field() functionality on ORACLE.
 868          * Caching is present for reducing query time.
 869          * For internal calls. Use fieldInfo for normal usage.
 870          * Returns false if the field doesn't exist
 871          *
 872          * @param array|string $table
 873          * @param string $field
 874          * @return ORAField|ORAResult|false
 875          */
 876         private function fieldInfoMulti( $table, $field ) {
 877                 $field = strtoupper( $field );
 878                 if ( is_array( $table ) ) {
 879                         $table = array_map( [ $this, 'tableNameInternal' ], $table );
 880                         $tableWhere = 'IN (';
 881                         foreach ( $table as &$singleTable ) {
 882                                 $singleTable = $this->removeIdentifierQuotes( $singleTable );
 883                                 if ( isset( $this->mFieldInfoCache["$singleTable.$field"] ) ) {
 884                                         return $this->mFieldInfoCache["$singleTable.$field"];
 885                                 }
 886                                 $tableWhere .= '\'' . $singleTable . '\',';
 887                         }
 888                         $tableWhere = rtrim( $tableWhere, ',' ) . ')';
 889                 } else {
 890                         $table = $this->removeIdentifierQuotes( $this->tableNameInternal( $table ) );
 891                         if ( isset( $this->mFieldInfoCache["$table.$field"] ) ) {
 892                                 return $this->mFieldInfoCache["$table.$field"];
 893                         }
 894                         $tableWhere = '= \'' . $table . '\'';
 895                 }
 896
 897                 $fieldInfoStmt = oci_parse(
 898                         $this->conn,
 899                         'SELECT * FROM wiki_field_info_full WHERE table_name ' .
 900                                 $tableWhere . ' and column_name = \'' . $field . '\''
 901                 );
 902                 if ( oci_execute( $fieldInfoStmt, $this->execFlags() ) === false ) {
 903                         $e = oci_error( $fieldInfoStmt );
 904                         $this->reportQueryError( $e['message'], $e['code'], 'fieldInfo QUERY', __METHOD__ );
 905
 906                         return false;
 907                 }
 908                 $res = new ORAResult( $this, $fieldInfoStmt );
 909                 if ( $res->numRows() == 0 ) {
 910                         if ( is_array( $table ) ) {
 911                                 foreach ( $table as &$singleTable ) {
 912                                         $this->mFieldInfoCache["$singleTable.$field"] = false;
 913                                 }
 914                         } else {
 915                                 $this->mFieldInfoCache["$table.$field"] = false;
 916                         }
 917                         $fieldInfoTemp = null;
 918                 } else {
 919                         $fieldInfoTemp = new ORAField( $res->fetchRow() );
 920                         $table = $fieldInfoTemp->tableName();
 921                         $this->mFieldInfoCache["$table.$field"] = $fieldInfoTemp;
 922                 }
 923                 $res->free();
 924
 925                 return $fieldInfoTemp;
 926         }
 927
 928         /**
 929          * @throws DBUnexpectedError
 930          * @param string $table
 931          * @param string $field
 932          * @return ORAField
 933          */
 934         function fieldInfo( $table, $field ) {
 935                 if ( is_array( $table ) ) {
 936                         throw new DBUnexpectedError(
 937                                 $this,
 938                                 'DatabaseOracle::fieldInfo called with table array!'
 939                         );
 940                 }
 941
 942                 return $this->fieldInfoMulti( $table, $field );
 943         }
 944
 945         protected function doBegin( $fname = __METHOD__ ) {
 946                 $this->trxLevel = 1;
 947                 $this->doQuery( 'SET CONSTRAINTS ALL DEFERRED' );
 948         }
 949
 950         protected function doCommit( $fname = __METHOD__ ) {
 951                 if ( $this->trxLevel ) {
 952                         $ret = oci_commit( $this->conn );
 953                         if ( !$ret ) {
 954                                 throw new DBUnexpectedError( $this, $this->lastError() );
 955                         }
 956                         $this->trxLevel = 0;
 957                         $this->doQuery( 'SET CONSTRAINTS ALL IMMEDIATE' );
 958                 }
 959         }
 960
 961         protected function doRollback( $fname = __METHOD__ ) {
 962                 if ( $this->trxLevel ) {
 963                         oci_rollback( $this->conn );
 964                         $this->trxLevel = 0;
 965                         $this->doQuery( 'SET CONSTRAINTS ALL IMMEDIATE' );
 966                 }
 967         }
 968
 969         function sourceStream(
 970                 $fp,
 971                 callable $lineCallback = null,
 972                 callable $resultCallback = null,
 973                 $fname = __METHOD__, callable $inputCallback = null
 974         ) {
 975                 $cmd = '';
 976                 $done = false;
 977                 $dollarquote = false;
 978
 979                 $replacements = [];
 980                 // Defines must comply with ^define\s*([^\s=]*)\s*=\s?'\{\$([^\}]*)\}';
 981                 while ( !feof( $fp ) ) {
 982                         if ( $lineCallback ) {
 983                                 $lineCallback();
 984                         }
 985                         $line = trim( fgets( $fp, 1024 ) );
 986                         $sl = strlen( $line ) - 1;
 987
 988                         if ( $sl < 0 ) {
 989                                 continue;
 990                         }
 991                         if ( $line[0] == '-' && $line[1] == '-' ) {
 992                                 continue;
 993                         }
 994
 995                         // Allow dollar quoting for function declarations
 996                         if ( substr( $line, 0, 8 ) == '/*$mw$*/' ) {
 997                                 if ( $dollarquote ) {
 998                                         $dollarquote = false;
 999                                         $line = str_replace( '/*$mw$*/', '', $line ); // remove dollarquotes
1000                                         $done = true;
1001                                 } else {
1002                                         $dollarquote = true;
1003                                 }
1004                         } elseif ( !$dollarquote ) {
1005                                 if ( $line[$sl] == ';' && ( $sl < 2 || $line[$sl - 1] != ';' ) ) {
1006                                         $done = true;
1007                                         $line = substr( $line, 0, $sl );
1008                                 }
1009                         }
1010
1011                         if ( $cmd != '' ) {
1012                                 $cmd .= ' ';
1013                         }
1014                         $cmd .= "$line\n";
1015
1016                         if ( $done ) {
1017                                 $cmd = str_replace( ';;', ";", $cmd );
1018                                 if ( strtolower( substr( $cmd, 0, 6 ) ) == 'define' ) {
1019                                         if ( preg_match( '/^define\s*([^\s=]*)\s*=\s*\'\{\$([^\}]*)\}\'/', $cmd, $defines ) ) {
1020                                                 $replacements[$defines[2]] = $defines[1];
1021                                         }
1022                                 } else {
1023                                         foreach ( $replacements as $mwVar => $scVar ) {
1024                                                 $cmd = str_replace( '&' . $scVar . '.', '`{$' . $mwVar . '}`', $cmd );
1025                                         }
1026
1027                                         $cmd = $this->replaceVars( $cmd );
1028                                         if ( $inputCallback ) {
1029                                                 $inputCallback( $cmd );
1030                                         }
1031                                         $res = $this->doQuery( $cmd );
1032                                         if ( $resultCallback ) {
1033                                                 call_user_func( $resultCallback, $res, $this );
1034                                         }
1035
1036                                         if ( $res === false ) {
1037                                                 $err = $this->lastError();
1038
1039                                                 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
1040                                         }
1041                                 }
1042
1043                                 $cmd = '';
1044                                 $done = false;
1045                         }
1046                 }
1047
1048                 return true;
1049         }
1050
1051         protected function doSelectDomain( DatabaseDomain $domain ) {
1052                 if ( $domain->getSchema() !== null ) {
1053                         // We use the *database* aspect of $domain for schema, not the domain schema
1054                         throw new DBExpectedError( $this, __CLASS__ . ": domain schemas are not supported." );
1055                 }
1056
1057                 $database = $domain->getDatabase();
1058                 if ( $database === null || $database === $this->user ) {
1059                         // Backward compatibility
1060                         $this->currentDomain = $domain;
1061
1062                         return true;
1063                 }
1064
1065                 // https://docs.oracle.com/javadb/10.8.3.0/ref/rrefsqlj32268.html
1066                 $encDatabase = $this->addIdentifierQuotes( strtoupper( $database ) );
1067                 $sql = "ALTER SESSION SET CURRENT_SCHEMA=$encDatabase";
1068                 $stmt = oci_parse( $this->conn, $sql );
1069                 Wikimedia\suppressWarnings();
1070                 $success = oci_execute( $stmt );
1071                 Wikimedia\restoreWarnings();
1072                 if ( $success ) {
1073                         // Update that domain fields on success (no exception thrown)
1074                         $this->currentDomain = $domain;
1075                 } else {
1076                         $e = oci_error( $stmt );
1077                         $this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
1078                 }
1079
1080                 return true;
1081         }
1082
1083         function strencode( $s ) {
1084                 return str_replace( "'", "''", $s );
1085         }
1086
1087         function addQuotes( $s ) {
1088                 return "'" . $this->strencode( $this->getVerifiedUTF8( $s ) ) . "'";
1089         }
1090
1091         public function addIdentifierQuotes( $s ) {
1092                 if ( !$this->getFlag( DBO_DDLMODE ) ) {
1093                         $s = '/*Q*/' . $s;
1094                 }
1095
1096                 return $s;
1097         }
1098
1099         public function removeIdentifierQuotes( $s ) {
1100                 return strpos( $s, '/*Q*/' ) === false ? $s : substr( $s, 5 );
1101         }
1102
1103         public function isQuotedIdentifier( $s ) {
1104                 return strpos( $s, '/*Q*/' ) !== false;
1105         }
1106
1107         private function wrapFieldForWhere( $table, &$col, &$val ) {
1108                 $col_info = $this->fieldInfoMulti( $table, $col );
1109                 $col_type = $col_info != false ? $col_info->type() : 'CONSTANT';
1110                 if ( $col_type == 'CLOB' ) {
1111                         $col = 'TO_CHAR(' . $col . ')';
1112                         $val = $this->getVerifiedUTF8( $val );
1113                 } elseif ( $col_type == 'VARCHAR2' ) {
1114                         $val = $this->getVerifiedUTF8( $val );
1115                 }
1116         }
1117
1118         private function wrapConditionsForWhere( $table, $conds, $parentCol = null ) {
1119                 $conds2 = [];
1120                 foreach ( $conds as $col => $val ) {
1121                         if ( is_array( $val ) ) {
1122                                 $conds2[$col] = $this->wrapConditionsForWhere( $table, $val, $col );
1123                         } else {
1124                                 if ( is_numeric( $col ) && $parentCol != null ) {
1125                                         $this->wrapFieldForWhere( $table, $parentCol, $val );
1126                                 } else {
1127                                         $this->wrapFieldForWhere( $table, $col, $val );
1128                                 }
1129                                 $conds2[$col] = $val;
1130                         }
1131                 }
1132
1133                 return $conds2;
1134         }
1135
1136         function selectRow( $table, $vars, $conds, $fname = __METHOD__,
1137                 $options = [], $join_conds = []
1138         ) {
1139                 if ( is_array( $conds ) ) {
1140                         $conds = $this->wrapConditionsForWhere( $table, $conds );
1141                 }
1142
1143                 return parent::selectRow( $table, $vars, $conds, $fname, $options, $join_conds );
1144         }
1145
1146         /**
1147          * Returns an optional USE INDEX clause to go after the table, and a
1148          * string to go at the end of the query
1149          *
1150          * @param array $options An associative array of options to be turned into
1151          *   an SQL query, valid keys are listed in the function.
1152          * @return array
1153          */
1154         function makeSelectOptions( $options ) {
1155                 $preLimitTail = $postLimitTail = '';
1156                 $startOpts = '';
1157
1158                 $noKeyOptions = [];
1159                 foreach ( $options as $key => $option ) {
1160                         if ( is_numeric( $key ) ) {
1161                                 $noKeyOptions[$option] = true;
1162                         }
1163                 }
1164
1165                 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1166
1167                 $preLimitTail .= $this->makeOrderBy( $options );
1168
1169                 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1170                         $postLimitTail .= ' FOR UPDATE';
1171                 }
1172
1173                 if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
1174                         $startOpts .= 'DISTINCT';
1175                 }
1176
1177                 if ( isset( $options['USE INDEX'] ) && !is_array( $options['USE INDEX'] ) ) {
1178                         $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1179                 } else {
1180                         $useIndex = '';
1181                 }
1182
1183                 if ( isset( $options['IGNORE INDEX'] ) && !is_array( $options['IGNORE INDEX'] ) ) {
1184                         $ignoreIndex = $this->ignoreIndexClause( $options['IGNORE INDEX'] );
1185                 } else {
1186                         $ignoreIndex = '';
1187                 }
1188
1189                 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1190         }
1191
1192         public function delete( $table, $conds, $fname = __METHOD__ ) {
1193                 global $wgActorTableSchemaMigrationStage;
1194
1195                 if ( is_array( $conds ) ) {
1196                         $conds = $this->wrapConditionsForWhere( $table, $conds );
1197                 }
1198                 // a hack for deleting pages, users and images (which have non-nullable FKs)
1199                 // all deletions on these tables have transactions so final failure rollbacks these updates
1200                 // @todo: Normalize the schema to match MySQL, no special FKs and such
1201                 $table = $this->tableName( $table );
1202                 if ( $table == $this->tableName( 'user' ) &&
1203                         ( $wgActorTableSchemaMigrationStage & SCHEMA_COMPAT_WRITE_OLD )
1204                 ) {
1205                         $this->update( 'archive', [ 'ar_user' => 0 ],
1206                                 [ 'ar_user' => $conds['user_id'] ], $fname );
1207                         $this->update( 'ipblocks', [ 'ipb_user' => 0 ],
1208                                 [ 'ipb_user' => $conds['user_id'] ], $fname );
1209                         $this->update( 'image', [ 'img_user' => 0 ],
1210                                 [ 'img_user' => $conds['user_id'] ], $fname );
1211                         $this->update( 'oldimage', [ 'oi_user' => 0 ],
1212                                 [ 'oi_user' => $conds['user_id'] ], $fname );
1213                         $this->update( 'filearchive', [ 'fa_deleted_user' => 0 ],
1214                                 [ 'fa_deleted_user' => $conds['user_id'] ], $fname );
1215                         $this->update( 'filearchive', [ 'fa_user' => 0 ],
1216                                 [ 'fa_user' => $conds['user_id'] ], $fname );
1217                         $this->update( 'uploadstash', [ 'us_user' => 0 ],
1218                                 [ 'us_user' => $conds['user_id'] ], $fname );
1219                         $this->update( 'recentchanges', [ 'rc_user' => 0 ],
1220                                 [ 'rc_user' => $conds['user_id'] ], $fname );
1221                         $this->update( 'logging', [ 'log_user' => 0 ],
1222                                 [ 'log_user' => $conds['user_id'] ], $fname );
1223                 } elseif ( $table == $this->tableName( 'image' ) ) {
1224                         $this->update( 'oldimage', [ 'oi_name' => 0 ],
1225                                 [ 'oi_name' => $conds['img_name'] ], $fname );
1226                 }
1227
1228                 return parent::delete( $table, $conds, $fname );
1229         }
1230
1231         /**
1232          * @param string $table
1233          * @param array $values
1234          * @param array $conds
1235          * @param string $fname
1236          * @param array $options
1237          * @return bool
1238          * @throws DBUnexpectedError
1239          */
1240         function update( $table, $values, $conds, $fname = __METHOD__, $options = [] ) {
1241                 $table = $this->tableName( $table );
1242                 $opts = $this->makeUpdateOptions( $options );
1243                 $sql = "UPDATE $opts $table SET ";
1244
1245                 $first = true;
1246                 foreach ( $values as $col => &$val ) {
1247                         $sqlSet = $this->fieldBindStatement( $table, $col, $val, true );
1248
1249                         if ( !$first ) {
1250                                 $sqlSet = ', ' . $sqlSet;
1251                         } else {
1252                                 $first = false;
1253                         }
1254                         $sql .= $sqlSet;
1255                 }
1256
1257                 if ( $conds !== [] && $conds !== '*' ) {
1258                         $conds = $this->wrapConditionsForWhere( $table, $conds );
1259                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
1260                 }
1261
1262                 $this->mLastResult = $stmt = oci_parse( $this->conn, $sql );
1263                 if ( $stmt === false ) {
1264                         $e = oci_error( $this->conn );
1265                         $this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
1266
1267                         return false;
1268                 }
1269                 foreach ( $values as $col => &$val ) {
1270                         $col_info = $this->fieldInfoMulti( $table, $col );
1271                         $col_type = $col_info != false ? $col_info->type() : 'CONSTANT';
1272
1273                         if ( $val === null ) {
1274                                 // do nothing ... null was inserted in statement creation
1275                         } elseif ( $col_type != 'BLOB' && $col_type != 'CLOB' ) {
1276                                 if ( is_object( $val ) ) {
1277                                         $val = $val->getData();
1278                                 }
1279
1280                                 if (
1281                                         preg_match( '/^timestamp.*/i', $col_type ) == 1 &&
1282                                         strtolower( $val ) == 'infinity'
1283                                 ) {
1284                                         $val = '31-12-2030 12:00:00.000000';
1285                                 }
1286
1287                                 $val = $this->getVerifiedUTF8( $val );
1288                                 if ( oci_bind_by_name( $stmt, ":$col", $val ) === false ) {
1289                                         $e = oci_error( $stmt );
1290                                         $this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
1291
1292                                         return false;
1293                                 }
1294                         } else {
1295                                 /** @var OCI_Lob[] $lob */
1296                                 $lob[$col] = oci_new_descriptor( $this->conn, OCI_D_LOB );
1297                                 if ( $lob[$col] === false ) {
1298                                         $e = oci_error( $stmt );
1299                                         throw new DBUnexpectedError(
1300                                                 $this,
1301                                                 "Cannot create LOB descriptor: " . $e['message']
1302                                         );
1303                                 }
1304
1305                                 if ( is_object( $val ) ) {
1306                                         $val = $val->getData();
1307                                 }
1308
1309                                 if ( $col_type == 'BLOB' ) {
1310                                         $lob[$col]->writeTemporary( $val );
1311                                         oci_bind_by_name( $stmt, ":$col", $lob[$col], -1, SQLT_BLOB );
1312                                 } else {
1313                                         $lob[$col]->writeTemporary( $val );
1314                                         oci_bind_by_name( $stmt, ":$col", $lob[$col], -1, OCI_B_CLOB );
1315                                 }
1316                         }
1317                 }
1318
1319                 Wikimedia\suppressWarnings();
1320
1321                 if ( oci_execute( $stmt, $this->execFlags() ) === false ) {
1322                         $e = oci_error( $stmt );
1323                         if ( !$this->ignoreDupValOnIndex || $e['code'] != '1' ) {
1324                                 $this->reportQueryError( $e['message'], $e['code'], $sql, __METHOD__ );
1325
1326                                 return false;
1327                         } else {
1328                                 $this->mAffectedRows = oci_num_rows( $stmt );
1329                         }
1330                 } else {
1331                         $this->mAffectedRows = oci_num_rows( $stmt );
1332                 }
1333
1334                 Wikimedia\restoreWarnings();
1335
1336                 if ( isset( $lob ) ) {
1337                         foreach ( $lob as $lob_v ) {
1338                                 $lob_v->free();
1339                         }
1340                 }
1341
1342                 if ( !$this->trxLevel ) {
1343                         oci_commit( $this->conn );
1344                 }
1345
1346                 return oci_free_statement( $stmt );
1347         }
1348
1349         function bitNot( $field ) {
1350                 // expecting bit-fields smaller than 4bytes
1351                 return 'BITNOT(' . $field . ')';
1352         }
1353
1354         function bitAnd( $fieldLeft, $fieldRight ) {
1355                 return 'BITAND(' . $fieldLeft . ', ' . $fieldRight . ')';
1356         }
1357
1358         function bitOr( $fieldLeft, $fieldRight ) {
1359                 return 'BITOR(' . $fieldLeft . ', ' . $fieldRight . ')';
1360         }
1361
1362         public function buildGroupConcatField(
1363                 $delim, $table, $field, $conds = '', $join_conds = []
1364         ) {
1365                 $fld = "LISTAGG($field," . $this->addQuotes( $delim ) . ") WITHIN GROUP (ORDER BY $field)";
1366
1367                 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
1368         }
1369
1370         public function buildSubstring( $input, $startPosition, $length = null ) {
1371                 $this->assertBuildSubstringParams( $startPosition, $length );
1372                 $params = [ $input, $startPosition ];
1373                 if ( $length !== null ) {
1374                         $params[] = $length;
1375                 }
1376                 return 'SUBSTR(' . implode( ',', $params ) . ')';
1377         }
1378
1379         /**
1380          * @param string $field Field or column to cast
1381          * @return string
1382          * @since 1.28
1383          */
1384         public function buildStringCast( $field ) {
1385                 return 'CAST ( ' . $field . ' AS VARCHAR2 )';
1386         }
1387
1388         public function getInfinity() {
1389                 return '31-12-2030 12:00:00.000000';
1390         }
1391
1392         /**
1393          * @param string $s
1394          * @return string
1395          */
1396         private function getVerifiedUTF8( $s ) {
1397                 if ( mb_check_encoding( (string)$s, 'UTF-8' ) ) {
1398                         return $s; // valid
1399                 }
1400
1401                 throw new DBUnexpectedError( $this, "Non BLOB/CLOB field must be UTF-8." );
1402         }
1403 }