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