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- Bug fixes for general core bugs in 3.10.x will end 8 November 2021 (12 months).
- Bug fixes for security issues in 3.10.x will end 9 May 2022 (18 months).
- PHP version: minimum PHP 7.2.0 Note: minimum PHP version has increased since Moodle 3.8. PHP 7.3.x and 7.4.x are supported too.
/lib/dml/ -> oci_native_moodle_database.php (source)
Differences Between: [Versions 310 and 311] [Versions 310 and 400] [Versions 310 and 401] [Versions 310 and 402] [Versions 310 and 403]
1 <?php 2 // This file is part of Moodle - http://moodle.org/ 3 // 4 // Moodle is free software: you can redistribute it and/or modify 5 // it under the terms of the GNU General Public License as published by 6 // the Free Software Foundation, either version 3 of the License, or 7 // (at your option) any later version. 8 // 9 // Moodle is distributed in the hope that it will be useful, 10 // but WITHOUT ANY WARRANTY; without even the implied warranty of 11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 // GNU General Public License for more details. 13 // 14 // You should have received a copy of the GNU General Public License 15 // along with Moodle. If not, see <http://www.gnu.org/licenses/>. 16 17 /** 18 * Native oci class representing moodle database interface. 19 * 20 * @package core_dml 21 * @copyright 2008 Petr Skoda (http://skodak.org) 22 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later 23 */ 24 25 defined('MOODLE_INTERNAL') || die(); 26 27 require_once (__DIR__.'/moodle_database.php'); 28 require_once (__DIR__.'/oci_native_moodle_recordset.php'); 29 require_once (__DIR__.'/oci_native_moodle_temptables.php'); 30 31 /** 32 * Native oci class representing moodle database interface. 33 * 34 * One complete reference for PHP + OCI: 35 * http://www.oracle.com/technology/tech/php/underground-php-oracle-manual.html 36 * 37 * @package core_dml 38 * @copyright 2008 Petr Skoda (http://skodak.org) 39 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later 40 */ 41 class oci_native_moodle_database extends moodle_database { 42 43 protected $oci = null; 44 45 /** @var To store stmt errors and enable get_last_error() to detect them.*/ 46 private $last_stmt_error = null; 47 /** @var Default value initialised in connect method, we need the driver to be present.*/ 48 private $commit_status = null; 49 50 /** @var To handle oci driver default verbosity.*/ 51 private $last_error_reporting; 52 /** @var To store unique_session_id. Needed for temp tables unique naming.*/ 53 private $unique_session_id; 54 55 /** 56 * Detects if all needed PHP stuff installed. 57 * Note: can be used before connect() 58 * @return mixed true if ok, string if something 59 */ 60 public function driver_installed() { 61 if (!extension_loaded('oci8')) { 62 return get_string('ociextensionisnotpresentinphp', 'install'); 63 } 64 return true; 65 } 66 67 /** 68 * Returns database family type - describes SQL dialect 69 * Note: can be used before connect() 70 * @return string db family name (mysql, postgres, mssql, oracle, etc.) 71 */ 72 public function get_dbfamily() { 73 return 'oracle'; 74 } 75 76 /** 77 * Returns more specific database driver type 78 * Note: can be used before connect() 79 * @return string db type mysqli, pgsql, oci, mssql, sqlsrv 80 */ 81 protected function get_dbtype() { 82 return 'oci'; 83 } 84 85 /** 86 * Returns general database library name 87 * Note: can be used before connect() 88 * @return string db type pdo, native 89 */ 90 protected function get_dblibrary() { 91 return 'native'; 92 } 93 94 /** 95 * Returns localised database type name 96 * Note: can be used before connect() 97 * @return string 98 */ 99 public function get_name() { 100 return get_string('nativeoci', 'install'); 101 } 102 103 /** 104 * Returns localised database configuration help. 105 * Note: can be used before connect() 106 * @return string 107 */ 108 public function get_configuration_help() { 109 return get_string('nativeocihelp', 'install'); 110 } 111 112 /** 113 * Diagnose database and tables, this function is used 114 * to verify database and driver settings, db engine types, etc. 115 * 116 * @return string null means everything ok, string means problem found. 117 */ 118 public function diagnose() { 119 return null; 120 } 121 122 /** 123 * Connect to db 124 * Must be called before other methods. 125 * @param string $dbhost The database host. 126 * @param string $dbuser The database username. 127 * @param string $dbpass The database username's password. 128 * @param string $dbname The name of the database being connected to. 129 * @param mixed $prefix string means moodle db prefix, false used for external databases where prefix not used 130 * @param array $dboptions driver specific options 131 * @return bool true 132 * @throws dml_connection_exception if error 133 */ 134 public function connect($dbhost, $dbuser, $dbpass, $dbname, $prefix, array $dboptions=null) { 135 if ($prefix == '' and !$this->external) { 136 //Enforce prefixes for everybody but mysql 137 throw new dml_exception('prefixcannotbeempty', $this->get_dbfamily()); 138 } 139 if (!$this->external and strlen($prefix) > 2) { 140 //Max prefix length for Oracle is 2cc 141 $a = (object)array('dbfamily'=>'oracle', 'maxlength'=>2); 142 throw new dml_exception('prefixtoolong', $a); 143 } 144 145 $driverstatus = $this->driver_installed(); 146 147 if ($driverstatus !== true) { 148 throw new dml_exception('dbdriverproblem', $driverstatus); 149 } 150 151 // Autocommit ON by default. 152 // Switching to OFF (OCI_DEFAULT), when playing with transactions 153 // please note this thing is not defined if oracle driver not present in PHP 154 // which means it can not be used as default value of object property! 155 $this->commit_status = OCI_COMMIT_ON_SUCCESS; 156 157 $this->store_settings($dbhost, $dbuser, $dbpass, $dbname, $prefix, $dboptions); 158 unset($this->dboptions['dbsocket']); 159 160 // NOTE: use of ', ", / and \ is very problematic, even native oracle tools seem to have 161 // problems with these, so just forget them and do not report problems into tracker... 162 163 if (empty($this->dbhost)) { 164 // old style full address (TNS) 165 $dbstring = $this->dbname; 166 } else { 167 if (empty($this->dboptions['dbport'])) { 168 $this->dboptions['dbport'] = 1521; 169 } 170 $dbstring = '//'.$this->dbhost.':'.$this->dboptions['dbport'].'/'.$this->dbname; 171 } 172 173 ob_start(); 174 if (empty($this->dboptions['dbpersist'])) { 175 $this->oci = oci_new_connect($this->dbuser, $this->dbpass, $dbstring, 'AL32UTF8'); 176 } else { 177 $this->oci = oci_pconnect($this->dbuser, $this->dbpass, $dbstring, 'AL32UTF8'); 178 } 179 $dberr = ob_get_contents(); 180 ob_end_clean(); 181 182 183 if ($this->oci === false) { 184 $this->oci = null; 185 $e = oci_error(); 186 if (isset($e['message'])) { 187 $dberr = $e['message']; 188 } 189 throw new dml_connection_exception($dberr); 190 } 191 192 // Disable logging until we are fully setup. 193 $this->query_log_prevent(); 194 195 // Make sure moodle package is installed - now required. 196 if (!$this->oci_package_installed()) { 197 try { 198 $this->attempt_oci_package_install(); 199 } catch (Exception $e) { 200 // Ignore problems, only the result counts, 201 // admins have to fix it manually if necessary. 202 } 203 if (!$this->oci_package_installed()) { 204 throw new dml_exception('dbdriverproblem', 'Oracle PL/SQL Moodle support package MOODLELIB is not installed! Database administrator has to execute /lib/dml/oci_native_moodle_package.sql script.'); 205 } 206 } 207 208 // get unique session id, to be used later for temp tables stuff 209 $sql = 'SELECT DBMS_SESSION.UNIQUE_SESSION_ID() FROM DUAL'; 210 $this->query_start($sql, null, SQL_QUERY_AUX); 211 $stmt = $this->parse_query($sql); 212 $result = oci_execute($stmt, $this->commit_status); 213 $this->query_end($result, $stmt); 214 $records = null; 215 oci_fetch_all($stmt, $records, 0, -1, OCI_FETCHSTATEMENT_BY_ROW); 216 oci_free_statement($stmt); 217 $this->unique_session_id = reset($records[0]); 218 219 //note: do not send "ALTER SESSION SET NLS_NUMERIC_CHARACTERS='.,'" ! 220 // instead fix our PHP code to convert "," to "." properly! 221 222 // We can enable logging now. 223 $this->query_log_allow(); 224 225 // Connection stabilised and configured, going to instantiate the temptables controller 226 $this->temptables = new oci_native_moodle_temptables($this, $this->unique_session_id); 227 228 return true; 229 } 230 231 /** 232 * Close database connection and release all resources 233 * and memory (especially circular memory references). 234 * Do NOT use connect() again, create a new instance if needed. 235 */ 236 public function dispose() { 237 parent::dispose(); // Call parent dispose to write/close session and other common stuff before closing connection 238 if ($this->oci) { 239 oci_close($this->oci); 240 $this->oci = null; 241 } 242 } 243 244 245 /** 246 * Called before each db query. 247 * @param string $sql 248 * @param array array of parameters 249 * @param int $type type of query 250 * @param mixed $extrainfo driver specific extra information 251 * @return void 252 */ 253 protected function query_start($sql, array $params=null, $type, $extrainfo=null) { 254 parent::query_start($sql, $params, $type, $extrainfo); 255 // oci driver tents to send debug to output, we do not need that ;-) 256 $this->last_error_reporting = error_reporting(0); 257 } 258 259 /** 260 * Called immediately after each db query. 261 * @param mixed db specific result 262 * @return void 263 */ 264 protected function query_end($result, $stmt=null) { 265 // reset original debug level 266 error_reporting($this->last_error_reporting); 267 if ($stmt and $result === false) { 268 // Look for stmt error and store it 269 if (is_resource($stmt)) { 270 $e = oci_error($stmt); 271 if ($e !== false) { 272 $this->last_stmt_error = $e['message']; 273 } 274 } 275 oci_free_statement($stmt); 276 } 277 parent::query_end($result); 278 } 279 280 /** 281 * Returns database server info array 282 * @return array Array containing 'description' and 'version' info 283 */ 284 public function get_server_info() { 285 static $info = null; // TODO: move to real object property 286 287 if (is_null($info)) { 288 $this->query_start("--oci_server_version()", null, SQL_QUERY_AUX); 289 $description = oci_server_version($this->oci); 290 $this->query_end(true); 291 preg_match('/(\d+\.)+\d+/', $description, $matches); 292 $info = array('description'=>$description, 'version'=>$matches[0]); 293 } 294 295 return $info; 296 } 297 298 /** 299 * Converts short table name {tablename} to real table name 300 * supporting temp tables ($this->unique_session_id based) if detected 301 * 302 * @param string sql 303 * @return string sql 304 */ 305 protected function fix_table_names($sql) { 306 if (preg_match_all('/\{([a-z][a-z0-9_]*)\}/', $sql, $matches)) { 307 foreach($matches[0] as $key=>$match) { 308 $name = $matches[1][$key]; 309 if ($this->temptables && $this->temptables->is_temptable($name)) { 310 $sql = str_replace($match, $this->temptables->get_correct_name($name), $sql); 311 } else { 312 $sql = str_replace($match, $this->prefix.$name, $sql); 313 } 314 } 315 } 316 return $sql; 317 } 318 319 /** 320 * Returns supported query parameter types 321 * @return int bitmask of accepted SQL_PARAMS_* 322 */ 323 protected function allowed_param_types() { 324 return SQL_PARAMS_NAMED; 325 } 326 327 /** 328 * Returns last error reported by database engine. 329 * @return string error message 330 */ 331 public function get_last_error() { 332 $error = false; 333 // First look for any previously saved stmt error 334 if (!empty($this->last_stmt_error)) { 335 $error = $this->last_stmt_error; 336 $this->last_stmt_error = null; 337 } else { // Now try connection error 338 $e = oci_error($this->oci); 339 if ($e !== false) { 340 $error = $e['message']; 341 } 342 } 343 return $error; 344 } 345 346 /** 347 * Prepare the statement for execution 348 * 349 * @param string $sql 350 * @return resource 351 * 352 * @throws dml_exception 353 */ 354 protected function parse_query($sql) { 355 $stmt = oci_parse($this->oci, $sql); 356 if ($stmt == false) { 357 throw new dml_exception('dmlparseexception', null, $this->get_last_error()); 358 } 359 return $stmt; 360 } 361 362 /** 363 * Make sure there are no reserved words in param names... 364 * @param string $sql 365 * @param array $params 366 * @return array ($sql, $params) updated query and parameters 367 */ 368 protected function tweak_param_names($sql, array $params) { 369 if (empty($params)) { 370 return array($sql, $params); 371 } 372 373 $newparams = array(); 374 $searcharr = array(); // search => replace pairs 375 foreach ($params as $name => $value) { 376 // Keep the name within the 30 chars limit always (prefixing/replacing) 377 if (strlen($name) <= 28) { 378 $newname = 'o_' . $name; 379 } else { 380 $newname = 'o_' . substr($name, 2); 381 } 382 $newparams[$newname] = $value; 383 $searcharr[':' . $name] = ':' . $newname; 384 } 385 // sort by length desc to avoid potential str_replace() overlap 386 uksort($searcharr, array('oci_native_moodle_database', 'compare_by_length_desc')); 387 388 $sql = str_replace(array_keys($searcharr), $searcharr, $sql); 389 return array($sql, $newparams); 390 } 391 392 /** 393 * Return tables in database WITHOUT current prefix 394 * @param bool $usecache if true, returns list of cached tables. 395 * @return array of table names in lowercase and without prefix 396 */ 397 public function get_tables($usecache=true) { 398 if ($usecache and $this->tables !== null) { 399 return $this->tables; 400 } 401 $this->tables = array(); 402 $prefix = str_replace('_', "\\_", strtoupper($this->prefix)); 403 $sql = "SELECT TABLE_NAME 404 FROM CAT 405 WHERE TABLE_TYPE='TABLE' 406 AND TABLE_NAME NOT LIKE 'BIN\$%' 407 AND TABLE_NAME LIKE '$prefix%' ESCAPE '\\'"; 408 $this->query_start($sql, null, SQL_QUERY_AUX); 409 $stmt = $this->parse_query($sql); 410 $result = oci_execute($stmt, $this->commit_status); 411 $this->query_end($result, $stmt); 412 $records = null; 413 oci_fetch_all($stmt, $records, 0, -1, OCI_ASSOC); 414 oci_free_statement($stmt); 415 $records = array_map('strtolower', $records['TABLE_NAME']); 416 foreach ($records as $tablename) { 417 if ($this->prefix !== false && $this->prefix !== '') { 418 if (strpos($tablename, $this->prefix) !== 0) { 419 continue; 420 } 421 $tablename = substr($tablename, strlen($this->prefix)); 422 } 423 $this->tables[$tablename] = $tablename; 424 } 425 426 // Add the currently available temptables 427 $this->tables = array_merge($this->tables, $this->temptables->get_temptables()); 428 429 return $this->tables; 430 } 431 432 /** 433 * Return table indexes - everything lowercased. 434 * @param string $table The table we want to get indexes from. 435 * @return array An associative array of indexes containing 'unique' flag and 'columns' being indexed 436 */ 437 public function get_indexes($table) { 438 $indexes = array(); 439 $tablename = strtoupper($this->prefix.$table); 440 441 $sql = "SELECT i.INDEX_NAME, i.UNIQUENESS, c.COLUMN_POSITION, c.COLUMN_NAME, ac.CONSTRAINT_TYPE 442 FROM ALL_INDEXES i 443 JOIN ALL_IND_COLUMNS c ON c.INDEX_NAME=i.INDEX_NAME 444 LEFT JOIN ALL_CONSTRAINTS ac ON (ac.TABLE_NAME=i.TABLE_NAME AND ac.CONSTRAINT_NAME=i.INDEX_NAME AND ac.CONSTRAINT_TYPE='P') 445 WHERE i.TABLE_NAME = '$tablename' 446 ORDER BY i.INDEX_NAME, c.COLUMN_POSITION"; 447 448 $stmt = $this->parse_query($sql); 449 $result = oci_execute($stmt, $this->commit_status); 450 $this->query_end($result, $stmt); 451 $records = null; 452 oci_fetch_all($stmt, $records, 0, -1, OCI_FETCHSTATEMENT_BY_ROW); 453 oci_free_statement($stmt); 454 455 foreach ($records as $record) { 456 if ($record['CONSTRAINT_TYPE'] === 'P') { 457 //ignore for now; 458 continue; 459 } 460 $indexname = strtolower($record['INDEX_NAME']); 461 if (!isset($indexes[$indexname])) { 462 $indexes[$indexname] = array('primary' => ($record['CONSTRAINT_TYPE'] === 'P'), 463 'unique' => ($record['UNIQUENESS'] === 'UNIQUE'), 464 'columns' => array()); 465 } 466 $indexes[$indexname]['columns'][] = strtolower($record['COLUMN_NAME']); 467 } 468 469 return $indexes; 470 } 471 472 /** 473 * Fetches detailed information about columns in table. 474 * 475 * @param string $table name 476 * @return array array of database_column_info objects indexed with column names 477 */ 478 protected function fetch_columns(string $table): array { 479 $structure = array(); 480 481 // We give precedence to CHAR_LENGTH for VARCHAR2 columns over WIDTH because the former is always 482 // BYTE based and, for cross-db operations, we want CHAR based results. See MDL-29415 483 // Instead of guessing sequence based exclusively on name, check tables against user_triggers to 484 // ensure the table has a 'before each row' trigger to assume 'id' is auto_increment. MDL-32365 485 $sql = "SELECT CNAME, COLTYPE, nvl(CHAR_LENGTH, WIDTH) AS WIDTH, SCALE, PRECISION, NULLS, DEFAULTVAL, 486 DECODE(NVL(TRIGGER_NAME, '0'), '0', '0', '1') HASTRIGGER 487 FROM COL c 488 LEFT JOIN USER_TAB_COLUMNS u ON (u.TABLE_NAME = c.TNAME AND u.COLUMN_NAME = c.CNAME AND u.DATA_TYPE = 'VARCHAR2') 489 LEFT JOIN USER_TRIGGERS t ON (t.TABLE_NAME = c.TNAME AND TRIGGER_TYPE = 'BEFORE EACH ROW' AND c.CNAME = 'ID') 490 WHERE TNAME = UPPER('{" . $table . "}') 491 ORDER BY COLNO"; 492 493 list($sql, $params, $type) = $this->fix_sql_params($sql, null); 494 495 $this->query_start($sql, null, SQL_QUERY_AUX); 496 $stmt = $this->parse_query($sql); 497 $result = oci_execute($stmt, $this->commit_status); 498 $this->query_end($result, $stmt); 499 $records = null; 500 oci_fetch_all($stmt, $records, 0, -1, OCI_FETCHSTATEMENT_BY_ROW); 501 oci_free_statement($stmt); 502 503 if (!$records) { 504 return array(); 505 } 506 foreach ($records as $rawcolumn) { 507 $rawcolumn = (object)$rawcolumn; 508 509 $info = new stdClass(); 510 $info->name = strtolower($rawcolumn->CNAME); 511 $info->auto_increment = ((int)$rawcolumn->HASTRIGGER) ? true : false; 512 $matches = null; 513 514 if ($rawcolumn->COLTYPE === 'VARCHAR2' 515 or $rawcolumn->COLTYPE === 'VARCHAR' 516 or $rawcolumn->COLTYPE === 'NVARCHAR2' 517 or $rawcolumn->COLTYPE === 'NVARCHAR' 518 or $rawcolumn->COLTYPE === 'CHAR' 519 or $rawcolumn->COLTYPE === 'NCHAR') { 520 $info->type = $rawcolumn->COLTYPE; 521 $info->meta_type = 'C'; 522 $info->max_length = $rawcolumn->WIDTH; 523 $info->scale = null; 524 $info->not_null = ($rawcolumn->NULLS === 'NOT NULL'); 525 $info->has_default = !is_null($rawcolumn->DEFAULTVAL); 526 if ($info->has_default) { 527 528 // this is hacky :-( 529 if ($rawcolumn->DEFAULTVAL === 'NULL') { 530 $info->default_value = null; 531 } else if ($rawcolumn->DEFAULTVAL === "' ' ") { // Sometimes it's stored with trailing space 532 $info->default_value = ""; 533 } else if ($rawcolumn->DEFAULTVAL === "' '") { // Sometimes it's stored without trailing space 534 $info->default_value = ""; 535 } else { 536 $info->default_value = trim($rawcolumn->DEFAULTVAL); // remove trailing space 537 $info->default_value = substr($info->default_value, 1, strlen($info->default_value)-2); //trim '' 538 } 539 } else { 540 $info->default_value = null; 541 } 542 $info->primary_key = false; 543 $info->binary = false; 544 $info->unsigned = null; 545 $info->unique = null; 546 547 } else if ($rawcolumn->COLTYPE === 'NUMBER') { 548 $info->type = $rawcolumn->COLTYPE; 549 $info->max_length = $rawcolumn->PRECISION; 550 $info->binary = false; 551 if (!is_null($rawcolumn->SCALE) && $rawcolumn->SCALE == 0) { // null in oracle scale allows decimals => not integer 552 // integer 553 if ($info->name === 'id') { 554 $info->primary_key = true; 555 $info->meta_type = 'R'; 556 $info->unique = true; 557 $info->has_default = false; 558 } else { 559 $info->primary_key = false; 560 $info->meta_type = 'I'; 561 $info->unique = null; 562 } 563 $info->scale = 0; 564 565 } else { 566 //float 567 $info->meta_type = 'N'; 568 $info->primary_key = false; 569 $info->unsigned = null; 570 $info->unique = null; 571 $info->scale = $rawcolumn->SCALE; 572 } 573 $info->not_null = ($rawcolumn->NULLS === 'NOT NULL'); 574 $info->has_default = !is_null($rawcolumn->DEFAULTVAL); 575 if ($info->has_default) { 576 $info->default_value = trim($rawcolumn->DEFAULTVAL); // remove trailing space 577 } else { 578 $info->default_value = null; 579 } 580 581 } else if ($rawcolumn->COLTYPE === 'FLOAT') { 582 $info->type = $rawcolumn->COLTYPE; 583 $info->max_length = (int)($rawcolumn->PRECISION * 3.32193); 584 $info->primary_key = false; 585 $info->meta_type = 'N'; 586 $info->unique = null; 587 $info->not_null = ($rawcolumn->NULLS === 'NOT NULL'); 588 $info->has_default = !is_null($rawcolumn->DEFAULTVAL); 589 if ($info->has_default) { 590 $info->default_value = trim($rawcolumn->DEFAULTVAL); // remove trailing space 591 } else { 592 $info->default_value = null; 593 } 594 595 } else if ($rawcolumn->COLTYPE === 'CLOB' 596 or $rawcolumn->COLTYPE === 'NCLOB') { 597 $info->type = $rawcolumn->COLTYPE; 598 $info->meta_type = 'X'; 599 $info->max_length = -1; 600 $info->scale = null; 601 $info->scale = null; 602 $info->not_null = ($rawcolumn->NULLS === 'NOT NULL'); 603 $info->has_default = !is_null($rawcolumn->DEFAULTVAL); 604 if ($info->has_default) { 605 // this is hacky :-( 606 if ($rawcolumn->DEFAULTVAL === 'NULL') { 607 $info->default_value = null; 608 } else if ($rawcolumn->DEFAULTVAL === "' ' ") { // Sometimes it's stored with trailing space 609 $info->default_value = ""; 610 } else if ($rawcolumn->DEFAULTVAL === "' '") { // Other times it's stored without trailing space 611 $info->default_value = ""; 612 } else { 613 $info->default_value = trim($rawcolumn->DEFAULTVAL); // remove trailing space 614 $info->default_value = substr($info->default_value, 1, strlen($info->default_value)-2); //trim '' 615 } 616 } else { 617 $info->default_value = null; 618 } 619 $info->primary_key = false; 620 $info->binary = false; 621 $info->unsigned = null; 622 $info->unique = null; 623 624 } else if ($rawcolumn->COLTYPE === 'BLOB') { 625 $info->type = $rawcolumn->COLTYPE; 626 $info->meta_type = 'B'; 627 $info->max_length = -1; 628 $info->scale = null; 629 $info->scale = null; 630 $info->not_null = ($rawcolumn->NULLS === 'NOT NULL'); 631 $info->has_default = !is_null($rawcolumn->DEFAULTVAL); 632 if ($info->has_default) { 633 // this is hacky :-( 634 if ($rawcolumn->DEFAULTVAL === 'NULL') { 635 $info->default_value = null; 636 } else if ($rawcolumn->DEFAULTVAL === "' ' ") { // Sometimes it's stored with trailing space 637 $info->default_value = ""; 638 } else if ($rawcolumn->DEFAULTVAL === "' '") { // Sometimes it's stored without trailing space 639 $info->default_value = ""; 640 } else { 641 $info->default_value = trim($rawcolumn->DEFAULTVAL); // remove trailing space 642 $info->default_value = substr($info->default_value, 1, strlen($info->default_value)-2); //trim '' 643 } 644 } else { 645 $info->default_value = null; 646 } 647 $info->primary_key = false; 648 $info->binary = true; 649 $info->unsigned = null; 650 $info->unique = null; 651 652 } else { 653 // unknown type - sorry 654 $info->type = $rawcolumn->COLTYPE; 655 $info->meta_type = '?'; 656 } 657 658 $structure[$info->name] = new database_column_info($info); 659 } 660 661 return $structure; 662 } 663 664 /** 665 * Normalise values based in RDBMS dependencies (booleans, LOBs...) 666 * 667 * @param database_column_info $column column metadata corresponding with the value we are going to normalise 668 * @param mixed $value value we are going to normalise 669 * @return mixed the normalised value 670 */ 671 protected function normalise_value($column, $value) { 672 $this->detect_objects($value); 673 674 if (is_bool($value)) { // Always, convert boolean to int 675 $value = (int)$value; 676 677 } else if ($column->meta_type == 'B') { // BLOB detected, we return 'blob' array instead of raw value to allow 678 if (!is_null($value)) { // binding/executing code later to know about its nature 679 $value = array('blob' => $value); 680 } 681 682 } else if ($column->meta_type == 'X' && strlen($value) > 4000) { // CLOB detected (>4000 optimisation), we return 'clob' 683 if (!is_null($value)) { // array instead of raw value to allow binding/ 684 $value = array('clob' => (string)$value); // executing code later to know about its nature 685 } 686 687 } else if ($value === '') { 688 if ($column->meta_type == 'I' or $column->meta_type == 'F' or $column->meta_type == 'N') { 689 $value = 0; // prevent '' problems in numeric fields 690 } 691 } 692 return $value; 693 } 694 695 /** 696 * Transforms the sql and params in order to emulate the LIMIT clause available in other DBs 697 * 698 * @param string $sql the SQL select query to execute. 699 * @param array $params array of sql parameters 700 * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set). 701 * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set). 702 * @return array with the transformed sql and params updated 703 */ 704 private function get_limit_sql($sql, array $params = null, $limitfrom=0, $limitnum=0) { 705 706 list($limitfrom, $limitnum) = $this->normalise_limit_from_num($limitfrom, $limitnum); 707 // TODO: Add the /*+ FIRST_ROWS */ hint if there isn't another hint 708 709 if ($limitfrom and $limitnum) { 710 $sql = "SELECT oracle_o.* 711 FROM (SELECT oracle_i.*, rownum AS oracle_rownum 712 FROM ($sql) oracle_i 713 WHERE rownum <= :oracle_num_rows 714 ) oracle_o 715 WHERE oracle_rownum > :oracle_skip_rows"; 716 $params['oracle_num_rows'] = $limitfrom + $limitnum; 717 $params['oracle_skip_rows'] = $limitfrom; 718 719 } else if ($limitfrom and !$limitnum) { 720 $sql = "SELECT oracle_o.* 721 FROM (SELECT oracle_i.*, rownum AS oracle_rownum 722 FROM ($sql) oracle_i 723 ) oracle_o 724 WHERE oracle_rownum > :oracle_skip_rows"; 725 $params['oracle_skip_rows'] = $limitfrom; 726 727 } else if (!$limitfrom and $limitnum) { 728 $sql = "SELECT * 729 FROM ($sql) 730 WHERE rownum <= :oracle_num_rows"; 731 $params['oracle_num_rows'] = $limitnum; 732 } 733 734 return array($sql, $params); 735 } 736 737 /** 738 * This function will handle all the column values before being inserted/updated to DB for Oracle 739 * installations. This is because the "special feature" of Oracle where the empty string is 740 * equal to NULL and this presents a problem with all our currently NOT NULL default '' fields. 741 * (and with empties handling in general) 742 * 743 * Note that this function is 100% private and should be used, exclusively by DML functions 744 * in this file. Also, this is considered a DIRTY HACK to be removed when possible. 745 * 746 * This function is private and must not be used outside this driver at all 747 * 748 * @param $table string the table where the record is going to be inserted/updated (without prefix) 749 * @param $field string the field where the record is going to be inserted/updated 750 * @param $value mixed the value to be inserted/updated 751 */ 752 private function oracle_dirty_hack ($table, $field, $value) { 753 754 // General bound parameter, just hack the spaces and pray it will work. 755 if (!$table) { 756 if ($value === '') { 757 return ' '; 758 } else if (is_bool($value)) { 759 return (int)$value; 760 } else { 761 return $value; 762 } 763 } 764 765 // Get metadata 766 $columns = $this->get_columns($table); 767 if (!isset($columns[$field])) { 768 if ($value === '') { 769 return ' '; 770 } else if (is_bool($value)) { 771 return (int)$value; 772 } else { 773 return $value; 774 } 775 } 776 $column = $columns[$field]; 777 778 // !! This paragraph explains behaviour before Moodle 2.0: 779 // 780 // For Oracle DB, empty strings are converted to NULLs in DB 781 // and this breaks a lot of NOT NULL columns currently Moodle. In the future it's 782 // planned to move some of them to NULL, if they must accept empty values and this 783 // piece of code will become less and less used. But, for now, we need it. 784 // What we are going to do is to examine all the data being inserted and if it's 785 // an empty string (NULL for Oracle) and the field is defined as NOT NULL, we'll modify 786 // such data in the best form possible ("0" for booleans and numbers and " " for the 787 // rest of strings. It isn't optimal, but the only way to do so. 788 // In the opposite, when retrieving records from Oracle, we'll decode " " back to 789 // empty strings to allow everything to work properly. DIRTY HACK. 790 791 // !! These paragraphs explain the rationale about the change for Moodle 2.5: 792 // 793 // Before Moodle 2.0, we only used to apply this DIRTY HACK to NOT NULL columns, as 794 // stated above, but it causes one problem in NULL columns where both empty strings 795 // and real NULLs are stored as NULLs, being impossible to differentiate them when 796 // being retrieved from DB. 797 // 798 // So, starting with Moodle 2.0, we are going to apply the DIRTY HACK to all the 799 // CHAR/CLOB columns no matter of their nullability. That way, when retrieving 800 // NULLABLE fields we'll get proper empties and NULLs differentiated, so we'll be able 801 // to rely in NULL/empty/content contents without problems, until now that wasn't 802 // possible at all. 803 // 804 // One space DIRTY HACK is now applied automatically for all query parameters 805 // and results. The only problem is string concatenation where the glue must 806 // be specified as "' '" sql fragment. 807 // 808 // !! Conclusions: 809 // 810 // From Moodle 2.5 onwards, ALL empty strings in Oracle DBs will be stored as 811 // 1-whitespace char, ALL NULLs as NULLs and, obviously, content as content. And 812 // those 1-whitespace chars will be converted back to empty strings by all the 813 // get_field/record/set() functions transparently and any SQL needing direct handling 814 // of empties will have to use placeholders or sql_isempty() helper function. 815 816 // If the field isn't VARCHAR or CLOB, skip 817 if ($column->meta_type != 'C' and $column->meta_type != 'X') { 818 return $value; 819 } 820 821 // If the value isn't empty, skip 822 if (!empty($value)) { 823 return $value; 824 } 825 826 // Now, we have one empty value, going to be inserted to one VARCHAR2 or CLOB field 827 // Try to get the best value to be inserted 828 829 // The '0' string doesn't need any transformation, skip 830 if ($value === '0') { 831 return $value; 832 } 833 834 // Transformations start 835 if (gettype($value) == 'boolean') { 836 return '0'; // Transform false to '0' that evaluates the same for PHP 837 838 } else if (gettype($value) == 'integer') { 839 return '0'; // Transform 0 to '0' that evaluates the same for PHP 840 841 } else if ($value === '') { 842 return ' '; // Transform '' to ' ' that DON'T EVALUATE THE SAME 843 // (we'll transform back again on get_records_XXX functions and others)!! 844 } 845 846 // Fail safe to original value 847 return $value; 848 } 849 850 /** 851 * Helper function to order by string length desc 852 * 853 * @param $a string first element to compare 854 * @param $b string second element to compare 855 * @return int < 0 $a goes first (is less), 0 $b goes first, 0 doesn't matter 856 */ 857 private function compare_by_length_desc($a, $b) { 858 return strlen($b) - strlen($a); 859 } 860 861 /** 862 * Is db in unicode mode? 863 * @return bool 864 */ 865 public function setup_is_unicodedb() { 866 $sql = "SELECT VALUE 867 FROM NLS_DATABASE_PARAMETERS 868 WHERE PARAMETER = 'NLS_CHARACTERSET'"; 869 $this->query_start($sql, null, SQL_QUERY_AUX); 870 $stmt = $this->parse_query($sql); 871 $result = oci_execute($stmt, $this->commit_status); 872 $this->query_end($result, $stmt); 873 $records = null; 874 oci_fetch_all($stmt, $records, 0, -1, OCI_FETCHSTATEMENT_BY_COLUMN); 875 oci_free_statement($stmt); 876 877 return (isset($records['VALUE'][0]) and $records['VALUE'][0] === 'AL32UTF8'); 878 } 879 880 /** 881 * Do NOT use in code, to be used by database_manager only! 882 * @param string|array $sql query 883 * @param array|null $tablenames an array of xmldb table names affected by this request. 884 * @return bool true 885 * @throws ddl_change_structure_exception A DDL specific exception is thrown for any errors. 886 */ 887 public function change_database_structure($sql, $tablenames = null) { 888 $this->get_manager(); // Includes DDL exceptions classes ;-) 889 $sqls = (array)$sql; 890 891 try { 892 foreach ($sqls as $sql) { 893 $this->query_start($sql, null, SQL_QUERY_STRUCTURE); 894 $stmt = $this->parse_query($sql); 895 $result = oci_execute($stmt, $this->commit_status); 896 $this->query_end($result, $stmt); 897 oci_free_statement($stmt); 898 } 899 } catch (ddl_change_structure_exception $e) { 900 $this->reset_caches($tablenames); 901 throw $e; 902 } 903 904 $this->reset_caches($tablenames); 905 return true; 906 } 907 908 protected function bind_params($stmt, array &$params=null, $tablename=null, array &$descriptors = null) { 909 if ($params) { 910 $columns = array(); 911 if ($tablename) { 912 $columns = $this->get_columns($tablename); 913 } 914 foreach($params as $key => $value) { 915 // Decouple column name and param name as far as sometimes they aren't the same 916 if ($key == 'o_newfieldtoset') { // found case where column and key diverge, handle that 917 $columnname = key($value); // columnname is the key of the array 918 $params[$key] = $value[$columnname]; // set the proper value in the $params array and 919 $value = $value[$columnname]; // set the proper value in the $value variable 920 } else { 921 $columnname = preg_replace('/^o_/', '', $key); // Default columnname (for DB introspecting is key), but... 922 } 923 // Continue processing 924 // Now, handle already detected LOBs 925 if (is_array($value)) { // Let's go to bind special cases (lob descriptors) 926 if (isset($value['clob'])) { 927 $lob = oci_new_descriptor($this->oci, OCI_DTYPE_LOB); 928 if ($descriptors === null) { 929 throw new coding_exception('moodle_database::bind_params() $descriptors not specified for clob'); 930 } 931 $descriptors[] = $lob; 932 oci_bind_by_name($stmt, $key, $lob, -1, SQLT_CLOB); 933 $lob->writeTemporary($this->oracle_dirty_hack($tablename, $columnname, $params[$key]['clob']), OCI_TEMP_CLOB); 934 continue; // Column binding finished, go to next one 935 } else if (isset($value['blob'])) { 936 $lob = oci_new_descriptor($this->oci, OCI_DTYPE_LOB); 937 if ($descriptors === null) { 938 throw new coding_exception('moodle_database::bind_params() $descriptors not specified for clob'); 939 } 940 $descriptors[] = $lob; 941 oci_bind_by_name($stmt, $key, $lob, -1, SQLT_BLOB); 942 $lob->writeTemporary($params[$key]['blob'], OCI_TEMP_BLOB); 943 continue; // Column binding finished, go to next one 944 } 945 } else { 946 // If, at this point, the param value > 4000 (bytes), let's assume it's a clob 947 // passed in an arbitrary sql (not processed by normalise_value() ever, 948 // and let's handle it as such. This will provide proper binding of CLOBs in 949 // conditions and other raw SQLs not covered by the above function. 950 if (strlen($value) > 4000) { 951 $lob = oci_new_descriptor($this->oci, OCI_DTYPE_LOB); 952 if ($descriptors === null) { 953 throw new coding_exception('moodle_database::bind_params() $descriptors not specified for clob'); 954 } 955 $descriptors[] = $lob; 956 oci_bind_by_name($stmt, $key, $lob, -1, SQLT_CLOB); 957 $lob->writeTemporary($this->oracle_dirty_hack($tablename, $columnname, $params[$key]), OCI_TEMP_CLOB); 958 continue; // Param binding finished, go to next one. 959 } 960 } 961 // TODO: Put proper types and length is possible (enormous speedup) 962 // Arrived here, continue with standard processing, using metadata if possible 963 if (isset($columns[$columnname])) { 964 $type = $columns[$columnname]->meta_type; 965 $maxlength = $columns[$columnname]->max_length; 966 } else { 967 $type = '?'; 968 $maxlength = -1; 969 } 970 switch ($type) { 971 case 'I': 972 case 'R': 973 // TODO: Optimise 974 oci_bind_by_name($stmt, $key, $params[$key]); 975 break; 976 977 case 'N': 978 case 'F': 979 // TODO: Optimise 980 oci_bind_by_name($stmt, $key, $params[$key]); 981 break; 982 983 case 'B': 984 // TODO: Only arrive here if BLOB is null: Bind if so, else exception! 985 // don't break here 986 987 case 'X': 988 // TODO: Only arrive here if CLOB is null or <= 4000 cc, else exception 989 // don't break here 990 991 default: // Bind as CHAR (applying dirty hack) 992 // TODO: Optimise 993 $params[$key] = $this->oracle_dirty_hack($tablename, $columnname, $params[$key]); 994 // Because of PHP7 bug (https://bugs.php.net/bug.php?id=72524) it seems that it's 995 // impossible to bind NULL values in a reliable way, let's use empty string 996 // instead in the mean time. 997 if ($params[$key] === null && version_compare(PHP_VERSION, '7.0.0', '>=')) { 998 $params[$key] = ''; 999 } 1000 oci_bind_by_name($stmt, $key, $params[$key]); 1001 } 1002 } 1003 } 1004 return $descriptors; 1005 } 1006 1007 protected function free_descriptors($descriptors) { 1008 foreach ($descriptors as $descriptor) { 1009 // Because all descriptors used in the driver come from LOB::writeTemporary() calls 1010 // we can safely close them here unconditionally. 1011 $descriptor->close(); 1012 // Free resources. 1013 oci_free_descriptor($descriptor); 1014 } 1015 } 1016 1017 /** 1018 * This function is used to convert all the Oracle 1-space defaults to the empty string 1019 * like a really DIRTY HACK to allow it to work better until all those NOT NULL DEFAULT '' 1020 * fields will be out from Moodle. 1021 * @param string the string to be converted to '' (empty string) if it's ' ' (one space) 1022 * @param mixed the key of the array in case we are using this function from array_walk, 1023 * defaults to null for other (direct) uses 1024 * @return boolean always true (the converted variable is returned by reference) 1025 */ 1026 public static function onespace2empty(&$item, $key=null) { 1027 $item = ($item === ' ') ? '' : $item; 1028 return true; 1029 } 1030 1031 /** 1032 * Execute general sql query. Should be used only when no other method suitable. 1033 * Do NOT use this to make changes in db structure, use database_manager methods instead! 1034 * @param string $sql query 1035 * @param array $params query parameters 1036 * @return bool true 1037 * @throws dml_exception A DML specific exception is thrown for any errors. 1038 */ 1039 public function execute($sql, array $params=null) { 1040 list($sql, $params, $type) = $this->fix_sql_params($sql, $params); 1041 1042 if (strpos($sql, ';') !== false) { 1043 throw new coding_exception('moodle_database::execute() Multiple sql statements found or bound parameters not used properly in query!'); 1044 } 1045 1046 list($sql, $params) = $this->tweak_param_names($sql, $params); 1047 $this->query_start($sql, $params, SQL_QUERY_UPDATE); 1048 $stmt = $this->parse_query($sql); 1049 $descriptors = array(); 1050 $this->bind_params($stmt, $params, null, $descriptors); 1051 $result = oci_execute($stmt, $this->commit_status); 1052 $this->free_descriptors($descriptors); 1053 $this->query_end($result, $stmt); 1054 oci_free_statement($stmt); 1055 1056 return true; 1057 } 1058 1059 /** 1060 * Get a single database record as an object using a SQL statement. 1061 * 1062 * The SQL statement should normally only return one record. 1063 * It is recommended to use get_records_sql() if more matches possible! 1064 * 1065 * @param string $sql The SQL string you wish to be executed, should normally only return one record. 1066 * @param array $params array of sql parameters 1067 * @param int $strictness IGNORE_MISSING means compatible mode, false returned if record not found, debug message if more found; 1068 * IGNORE_MULTIPLE means return first, ignore multiple records found(not recommended); 1069 * MUST_EXIST means throw exception if no record or multiple records found 1070 * @return mixed a fieldset object containing the first matching record, false or exception if error not found depending on mode 1071 * @throws dml_exception A DML specific exception is thrown for any errors. 1072 */ 1073 public function get_record_sql($sql, array $params=null, $strictness=IGNORE_MISSING) { 1074 $strictness = (int)$strictness; 1075 if ($strictness == IGNORE_MULTIPLE) { 1076 // do not limit here - ORA does not like that 1077 $rs = $this->get_recordset_sql($sql, $params); 1078 $result = false; 1079 foreach ($rs as $rec) { 1080 $result = $rec; 1081 break; 1082 } 1083 $rs->close(); 1084 return $result; 1085 } 1086 return parent::get_record_sql($sql, $params, $strictness); 1087 } 1088 1089 /** 1090 * Get a number of records as a moodle_recordset using a SQL statement. 1091 * 1092 * Since this method is a little less readable, use of it should be restricted to 1093 * code where it's possible there might be large datasets being returned. For known 1094 * small datasets use get_records_sql - it leads to simpler code. 1095 * 1096 * The return type is like: 1097 * @see function get_recordset. 1098 * 1099 * @param string $sql the SQL select query to execute. 1100 * @param array $params array of sql parameters 1101 * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set). 1102 * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set). 1103 * @return moodle_recordset instance 1104 * @throws dml_exception A DML specific exception is thrown for any errors. 1105 */ 1106 public function get_recordset_sql($sql, array $params=null, $limitfrom=0, $limitnum=0) { 1107 1108 list($sql, $params, $type) = $this->fix_sql_params($sql, $params); 1109 1110 list($rawsql, $params) = $this->get_limit_sql($sql, $params, $limitfrom, $limitnum); 1111 1112 list($rawsql, $params) = $this->tweak_param_names($rawsql, $params); 1113 $this->query_start($rawsql, $params, SQL_QUERY_SELECT); 1114 $stmt = $this->parse_query($rawsql); 1115 $descriptors = array(); 1116 $this->bind_params($stmt, $params, null, $descriptors); 1117 $result = oci_execute($stmt, $this->commit_status); 1118 $this->free_descriptors($descriptors); 1119 $this->query_end($result, $stmt); 1120 1121 return $this->create_recordset($stmt); 1122 } 1123 1124 protected function create_recordset($stmt) { 1125 return new oci_native_moodle_recordset($stmt); 1126 } 1127 1128 /** 1129 * Get a number of records as an array of objects using a SQL statement. 1130 * 1131 * Return value is like: 1132 * @see function get_records. 1133 * 1134 * @param string $sql the SQL select query to execute. The first column of this SELECT statement 1135 * must be a unique value (usually the 'id' field), as it will be used as the key of the 1136 * returned array. 1137 * @param array $params array of sql parameters 1138 * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set). 1139 * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set). 1140 * @return array of objects, or empty array if no records were found 1141 * @throws dml_exception A DML specific exception is thrown for any errors. 1142 */ 1143 public function get_records_sql($sql, array $params=null, $limitfrom=0, $limitnum=0) { 1144 1145 list($sql, $params, $type) = $this->fix_sql_params($sql, $params); 1146 1147 list($rawsql, $params) = $this->get_limit_sql($sql, $params, $limitfrom, $limitnum); 1148 1149 list($rawsql, $params) = $this->tweak_param_names($rawsql, $params); 1150 $this->query_start($rawsql, $params, SQL_QUERY_SELECT); 1151 $stmt = $this->parse_query($rawsql); 1152 $descriptors = array(); 1153 $this->bind_params($stmt, $params, null, $descriptors); 1154 $result = oci_execute($stmt, $this->commit_status); 1155 $this->free_descriptors($descriptors); 1156 $this->query_end($result, $stmt); 1157 1158 $records = null; 1159 oci_fetch_all($stmt, $records, 0, -1, OCI_FETCHSTATEMENT_BY_ROW); 1160 oci_free_statement($stmt); 1161 1162 $return = array(); 1163 1164 foreach ($records as $row) { 1165 $row = array_change_key_case($row, CASE_LOWER); 1166 unset($row['oracle_rownum']); 1167 array_walk($row, array('oci_native_moodle_database', 'onespace2empty')); 1168 $id = reset($row); 1169 if (isset($return[$id])) { 1170 $colname = key($row); 1171 debugging("Did you remember to make the first column something unique in your call to get_records? Duplicate value '$id' found in column '$colname'.", DEBUG_DEVELOPER); 1172 } 1173 $return[$id] = (object)$row; 1174 } 1175 1176 return $return; 1177 } 1178 1179 /** 1180 * Selects records and return values (first field) as an array using a SQL statement. 1181 * 1182 * @param string $sql The SQL query 1183 * @param array $params array of sql parameters 1184 * @return array of values 1185 * @throws dml_exception A DML specific exception is thrown for any errors. 1186 */ 1187 public function get_fieldset_sql($sql, array $params=null) { 1188 list($sql, $params, $type) = $this->fix_sql_params($sql, $params); 1189 1190 list($sql, $params) = $this->tweak_param_names($sql, $params); 1191 $this->query_start($sql, $params, SQL_QUERY_SELECT); 1192 $stmt = $this->parse_query($sql); 1193 $descriptors = array(); 1194 $this->bind_params($stmt, $params, null, $descriptors); 1195 $result = oci_execute($stmt, $this->commit_status); 1196 $this->free_descriptors($descriptors); 1197 $this->query_end($result, $stmt); 1198 1199 $records = null; 1200 oci_fetch_all($stmt, $records, 0, -1, OCI_FETCHSTATEMENT_BY_COLUMN); 1201 oci_free_statement($stmt); 1202 1203 $return = reset($records); 1204 array_walk($return, array('oci_native_moodle_database', 'onespace2empty')); 1205 1206 return $return; 1207 } 1208 1209 /** 1210 * Insert new record into database, as fast as possible, no safety checks, lobs not supported. 1211 * @param string $table name 1212 * @param mixed $params data record as object or array 1213 * @param bool $returnit return it of inserted record 1214 * @param bool $bulk true means repeated inserts expected 1215 * @param bool $customsequence true if 'id' included in $params, disables $returnid 1216 * @return bool|int true or new id 1217 * @throws dml_exception A DML specific exception is thrown for any errors. 1218 */ 1219 public function insert_record_raw($table, $params, $returnid=true, $bulk=false, $customsequence=false) { 1220 if (!is_array($params)) { 1221 $params = (array)$params; 1222 } 1223 1224 $returning = ""; 1225 1226 if ($customsequence) { 1227 if (!isset($params['id'])) { 1228 throw new coding_exception('moodle_database::insert_record_raw() id field must be specified if custom sequences used.'); 1229 } 1230 $returnid = false; 1231 } else { 1232 unset($params['id']); 1233 if ($returnid) { 1234 $returning = " RETURNING id INTO :oracle_id"; // crazy name nobody is ever going to use or parameter ;-) 1235 } 1236 } 1237 1238 if (empty($params)) { 1239 throw new coding_exception('moodle_database::insert_record_raw() no fields found.'); 1240 } 1241 1242 $fields = implode(',', array_keys($params)); 1243 $values = array(); 1244 foreach ($params as $pname => $value) { 1245 $values[] = ":$pname"; 1246 } 1247 $values = implode(',', $values); 1248 1249 $sql = "INSERT INTO {" . $table . "} ($fields) VALUES ($values)"; 1250 list($sql, $params, $type) = $this->fix_sql_params($sql, $params); 1251 $sql .= $returning; 1252 1253 $id = 0; 1254 1255 // note we don't need tweak_param_names() here. Placeholders are safe column names. MDL-28080 1256 // list($sql, $params) = $this->tweak_param_names($sql, $params); 1257 $this->query_start($sql, $params, SQL_QUERY_INSERT); 1258 $stmt = $this->parse_query($sql); 1259 if ($returning) { 1260 oci_bind_by_name($stmt, ":oracle_id", $id, 10, SQLT_INT); 1261 } 1262 $descriptors = array(); 1263 $this->bind_params($stmt, $params, $table, $descriptors); 1264 $result = oci_execute($stmt, $this->commit_status); 1265 $this->free_descriptors($descriptors); 1266 $this->query_end($result, $stmt); 1267 oci_free_statement($stmt); 1268 1269 if (!$returnid) { 1270 return true; 1271 } 1272 1273 if (!$returning) { 1274 die('TODO - implement oracle 9.2 insert support'); //TODO 1275 } 1276 1277 return (int)$id; 1278 } 1279 1280 /** 1281 * Insert a record into a table and return the "id" field if required. 1282 * 1283 * Some conversions and safety checks are carried out. Lobs are supported. 1284 * If the return ID isn't required, then this just reports success as true/false. 1285 * $data is an object containing needed data 1286 * @param string $table The database table to be inserted into 1287 * @param object|array $dataobject A data object with values for one or more fields in the record 1288 * @param bool $returnid Should the id of the newly created record entry be returned? If this option is not requested then true/false is returned. 1289 * @return bool|int true or new id 1290 * @throws dml_exception A DML specific exception is thrown for any errors. 1291 */ 1292 public function insert_record($table, $dataobject, $returnid=true, $bulk=false) { 1293 $dataobject = (array)$dataobject; 1294 1295 $columns = $this->get_columns($table); 1296 if (empty($columns)) { 1297 throw new dml_exception('ddltablenotexist', $table); 1298 } 1299 1300 $cleaned = array(); 1301 1302 foreach ($dataobject as $field=>$value) { 1303 if ($field === 'id') { 1304 continue; 1305 } 1306 if (!isset($columns[$field])) { // Non-existing table field, skip it 1307 continue; 1308 } 1309 $column = $columns[$field]; 1310 $cleaned[$field] = $this->normalise_value($column, $value); 1311 } 1312 1313 return $this->insert_record_raw($table, $cleaned, $returnid, $bulk); 1314 } 1315 1316 /** 1317 * Import a record into a table, id field is required. 1318 * Safety checks are NOT carried out. Lobs are supported. 1319 * 1320 * @param string $table name of database table to be inserted into 1321 * @param object $dataobject A data object with values for one or more fields in the record 1322 * @return bool true 1323 * @throws dml_exception A DML specific exception is thrown for any errors. 1324 */ 1325 public function import_record($table, $dataobject) { 1326 $dataobject = (array)$dataobject; 1327 1328 $columns = $this->get_columns($table); 1329 $cleaned = array(); 1330 1331 foreach ($dataobject as $field=>$value) { 1332 if (!isset($columns[$field])) { 1333 continue; 1334 } 1335 $column = $columns[$field]; 1336 $cleaned[$field] = $this->normalise_value($column, $value); 1337 } 1338 1339 return $this->insert_record_raw($table, $cleaned, false, true, true); 1340 } 1341 1342 /** 1343 * Update record in database, as fast as possible, no safety checks, lobs not supported. 1344 * @param string $table name 1345 * @param mixed $params data record as object or array 1346 * @param bool true means repeated updates expected 1347 * @return bool true 1348 * @throws dml_exception A DML specific exception is thrown for any errors. 1349 */ 1350 public function update_record_raw($table, $params, $bulk=false) { 1351 $params = (array)$params; 1352 1353 if (!isset($params['id'])) { 1354 throw new coding_exception('moodle_database::update_record_raw() id field must be specified.'); 1355 } 1356 1357 if (empty($params)) { 1358 throw new coding_exception('moodle_database::update_record_raw() no fields found.'); 1359 } 1360 1361 $sets = array(); 1362 foreach ($params as $field=>$value) { 1363 if ($field == 'id') { 1364 continue; 1365 } 1366 $sets[] = "$field = :$field"; 1367 } 1368 1369 $sets = implode(',', $sets); 1370 $sql = "UPDATE {" . $table . "} SET $sets WHERE id=:id"; 1371 list($sql, $params, $type) = $this->fix_sql_params($sql, $params); 1372 1373 // note we don't need tweak_param_names() here. Placeholders are safe column names. MDL-28080 1374 // list($sql, $params) = $this->tweak_param_names($sql, $params); 1375 $this->query_start($sql, $params, SQL_QUERY_UPDATE); 1376 $stmt = $this->parse_query($sql); 1377 $descriptors = array(); 1378 $this->bind_params($stmt, $params, $table, $descriptors); 1379 $result = oci_execute($stmt, $this->commit_status); 1380 $this->free_descriptors($descriptors); 1381 $this->query_end($result, $stmt); 1382 oci_free_statement($stmt); 1383 1384 return true; 1385 } 1386 1387 /** 1388 * Update a record in a table 1389 * 1390 * $dataobject is an object containing needed data 1391 * Relies on $dataobject having a variable "id" to 1392 * specify the record to update 1393 * 1394 * @param string $table The database table to be checked against. 1395 * @param object $dataobject An object with contents equal to fieldname=>fieldvalue. Must have an entry for 'id' to map to the table specified. 1396 * @param bool true means repeated updates expected 1397 * @return bool true 1398 * @throws dml_exception A DML specific exception is thrown for any errors. 1399 */ 1400 public function update_record($table, $dataobject, $bulk=false) { 1401 $dataobject = (array)$dataobject; 1402 1403 $columns = $this->get_columns($table); 1404 $cleaned = array(); 1405 1406 foreach ($dataobject as $field=>$value) { 1407 if (!isset($columns[$field])) { 1408 continue; 1409 } 1410 $column = $columns[$field]; 1411 $cleaned[$field] = $this->normalise_value($column, $value); 1412 } 1413 1414 $this->update_record_raw($table, $cleaned, $bulk); 1415 1416 return true; 1417 } 1418 1419 /** 1420 * Set a single field in every table record which match a particular WHERE clause. 1421 * 1422 * @param string $table The database table to be checked against. 1423 * @param string $newfield the field to set. 1424 * @param string $newvalue the value to set the field to. 1425 * @param string $select A fragment of SQL to be used in a where clause in the SQL call. 1426 * @param array $params array of sql parameters 1427 * @return bool true 1428 * @throws dml_exception A DML specific exception is thrown for any errors. 1429 */ 1430 public function set_field_select($table, $newfield, $newvalue, $select, array $params=null) { 1431 1432 if ($select) { 1433 $select = "WHERE $select"; 1434 } 1435 if (is_null($params)) { 1436 $params = array(); 1437 } 1438 1439 // Get column metadata 1440 $columns = $this->get_columns($table); 1441 $column = $columns[$newfield]; 1442 1443 $newvalue = $this->normalise_value($column, $newvalue); 1444 1445 list($select, $params, $type) = $this->fix_sql_params($select, $params); 1446 1447 if (is_bool($newvalue)) { 1448 $newvalue = (int)$newvalue; // prevent "false" problems 1449 } 1450 if (is_null($newvalue)) { 1451 $newsql = "$newfield = NULL"; 1452 } else { 1453 // Set the param to array ($newfield => $newvalue) and key to 'newfieldtoset' 1454 // name in the build sql. Later, bind_params() will detect the value array and 1455 // perform the needed modifications to allow the query to work. Note that 1456 // 'newfieldtoset' is one arbitrary name that hopefully won't be used ever 1457 // in order to avoid problems where the same field is used both in the set clause and in 1458 // the conditions. This was breaking badly in drivers using NAMED params like oci. 1459 $params['newfieldtoset'] = array($newfield => $newvalue); 1460 $newsql = "$newfield = :newfieldtoset"; 1461 } 1462 $sql = "UPDATE {" . $table . "} SET $newsql $select"; 1463 list($sql, $params, $type) = $this->fix_sql_params($sql, $params); 1464 1465 list($sql, $params) = $this->tweak_param_names($sql, $params); 1466 $this->query_start($sql, $params, SQL_QUERY_UPDATE); 1467 $stmt = $this->parse_query($sql); 1468 $descriptors = array(); 1469 $this->bind_params($stmt, $params, $table, $descriptors); 1470 $result = oci_execute($stmt, $this->commit_status); 1471 $this->free_descriptors($descriptors); 1472 $this->query_end($result, $stmt); 1473 oci_free_statement($stmt); 1474 1475 return true; 1476 } 1477 1478 /** 1479 * Delete one or more records from a table which match a particular WHERE clause. 1480 * 1481 * @param string $table The database table to be checked against. 1482 * @param string $select A fragment of SQL to be used in a where clause in the SQL call (used to define the selection criteria). 1483 * @param array $params array of sql parameters 1484 * @return bool true 1485 * @throws dml_exception A DML specific exception is thrown for any errors. 1486 */ 1487 public function delete_records_select($table, $select, array $params=null) { 1488 1489 if ($select) { 1490 $select = "WHERE $select"; 1491 } 1492 1493 $sql = "DELETE FROM {" . $table . "} $select"; 1494 1495 list($sql, $params, $type) = $this->fix_sql_params($sql, $params); 1496 1497 list($sql, $params) = $this->tweak_param_names($sql, $params); 1498 $this->query_start($sql, $params, SQL_QUERY_UPDATE); 1499 $stmt = $this->parse_query($sql); 1500 $descriptors = array(); 1501 $this->bind_params($stmt, $params, null, $descriptors); 1502 $result = oci_execute($stmt, $this->commit_status); 1503 $this->free_descriptors($descriptors); 1504 $this->query_end($result, $stmt); 1505 oci_free_statement($stmt); 1506 1507 return true; 1508 } 1509 1510 function sql_null_from_clause() { 1511 return ' FROM dual'; 1512 } 1513 1514 public function sql_bitand($int1, $int2) { 1515 return 'bitand((' . $int1 . '), (' . $int2 . '))'; 1516 } 1517 1518 public function sql_bitnot($int1) { 1519 return '((0 - (' . $int1 . ')) - 1)'; 1520 } 1521 1522 public function sql_bitor($int1, $int2) { 1523 return 'MOODLELIB.BITOR(' . $int1 . ', ' . $int2 . ')'; 1524 } 1525 1526 public function sql_bitxor($int1, $int2) { 1527 return 'MOODLELIB.BITXOR(' . $int1 . ', ' . $int2 . ')'; 1528 } 1529 1530 /** 1531 * Returns the SQL text to be used in order to perform module '%' 1532 * operation - remainder after division 1533 * 1534 * @param integer int1 first integer in the operation 1535 * @param integer int2 second integer in the operation 1536 * @return string the piece of SQL code to be used in your statement. 1537 */ 1538 public function sql_modulo($int1, $int2) { 1539 return 'MOD(' . $int1 . ', ' . $int2 . ')'; 1540 } 1541 1542 public function sql_cast_char2int($fieldname, $text=false) { 1543 if (!$text) { 1544 return ' CAST(' . $fieldname . ' AS INT) '; 1545 } else { 1546 return ' CAST(' . $this->sql_compare_text($fieldname) . ' AS INT) '; 1547 } 1548 } 1549 1550 public function sql_cast_char2real($fieldname, $text=false) { 1551 if (!$text) { 1552 return ' CAST(' . $fieldname . ' AS FLOAT) '; 1553 } else { 1554 return ' CAST(' . $this->sql_compare_text($fieldname) . ' AS FLOAT) '; 1555 } 1556 } 1557 1558 /** 1559 * Returns 'LIKE' part of a query. 1560 * 1561 * @param string $fieldname usually name of the table column 1562 * @param string $param usually bound query parameter (?, :named) 1563 * @param bool $casesensitive use case sensitive search 1564 * @param bool $accensensitive use accent sensitive search (not all databases support accent insensitive) 1565 * @param bool $notlike true means "NOT LIKE" 1566 * @param string $escapechar escape char for '%' and '_' 1567 * @return string SQL code fragment 1568 */ 1569 public function sql_like($fieldname, $param, $casesensitive = true, $accentsensitive = true, $notlike = false, $escapechar = '\\') { 1570 if (strpos($param, '%') !== false) { 1571 debugging('Potential SQL injection detected, sql_like() expects bound parameters (? or :named)'); 1572 } 1573 1574 $LIKE = $notlike ? 'NOT LIKE' : 'LIKE'; 1575 1576 // no accent sensitiveness here for now, sorry 1577 1578 if ($casesensitive) { 1579 return "$fieldname $LIKE $param ESCAPE '$escapechar'"; 1580 } else { 1581 return "LOWER($fieldname) $LIKE LOWER($param) ESCAPE '$escapechar'"; 1582 } 1583 } 1584 1585 public function sql_concat() { 1586 $arr = func_get_args(); 1587 if (empty($arr)) { 1588 return " ' ' "; 1589 } 1590 foreach ($arr as $k => $v) { 1591 if ($v === "' '") { 1592 $arr[$k] = "'*OCISP*'"; // New mega hack. 1593 } 1594 } 1595 $s = $this->recursive_concat($arr); 1596 return " MOODLELIB.UNDO_MEGA_HACK($s) "; 1597 } 1598 1599 public function sql_concat_join($separator="' '", $elements = array()) { 1600 if ($separator === "' '") { 1601 $separator = "'*OCISP*'"; // New mega hack. 1602 } 1603 foreach ($elements as $k => $v) { 1604 if ($v === "' '") { 1605 $elements[$k] = "'*OCISP*'"; // New mega hack. 1606 } 1607 } 1608 for ($n = count($elements)-1; $n > 0 ; $n--) { 1609 array_splice($elements, $n, 0, $separator); 1610 } 1611 if (empty($elements)) { 1612 return " ' ' "; 1613 } 1614 $s = $this->recursive_concat($elements); 1615 return " MOODLELIB.UNDO_MEGA_HACK($s) "; 1616 } 1617 1618 /** 1619 * Constructs 'IN()' or '=' sql fragment 1620 * 1621 * Method overriding {@link moodle_database::get_in_or_equal} to be able to get 1622 * more than 1000 elements working, to avoid ORA-01795. We use a pivoting technique 1623 * to be able to transform the params into virtual rows, so the original IN() 1624 * expression gets transformed into a subquery. Once more, be noted that we shouldn't 1625 * be using ever get_in_or_equal() with such number of parameters (proper subquery and/or 1626 * chunking should be used instead). 1627 * 1628 * @param mixed $items A single value or array of values for the expression. 1629 * @param int $type Parameter bounding type : SQL_PARAMS_QM or SQL_PARAMS_NAMED. 1630 * @param string $prefix Named parameter placeholder prefix (a unique counter value is appended to each parameter name). 1631 * @param bool $equal True means we want to equate to the constructed expression, false means we don't want to equate to it. 1632 * @param mixed $onemptyitems This defines the behavior when the array of items provided is empty. Defaults to false, 1633 * meaning throw exceptions. Other values will become part of the returned SQL fragment. 1634 * @throws coding_exception | dml_exception 1635 * @return array A list containing the constructed sql fragment and an array of parameters. 1636 */ 1637 public function get_in_or_equal($items, $type=SQL_PARAMS_QM, $prefix='param', $equal=true, $onemptyitems=false) { 1638 list($sql, $params) = parent::get_in_or_equal($items, $type, $prefix, $equal, $onemptyitems); 1639 1640 // Less than 1000 elements, nothing to do. 1641 if (count($params) < 1000) { 1642 return array($sql, $params); // Return unmodified. 1643 } 1644 1645 // Extract the interesting parts of the sql to rewrite. 1646 if (preg_match('!(^.*IN \()([^\)]*)(.*)$!', $sql, $matches) === false) { 1647 return array($sql, $params); // Return unmodified. 1648 } 1649 1650 $instart = $matches[1]; 1651 $insql = $matches[2]; 1652 $inend = $matches[3]; 1653 $newsql = ''; 1654 1655 // Some basic verification about the matching going ok. 1656 $insqlarr = explode(',', $insql); 1657 if (count($insqlarr) !== count($params)) { 1658 return array($sql, $params); // Return unmodified. 1659 } 1660 1661 // Arrived here, we need to chunk and pivot the params, building a new sql (params remain the same). 1662 $addunionclause = false; 1663 while ($chunk = array_splice($insqlarr, 0, 125)) { // Each chunk will handle up to 125 (+125 +1) elements (DECODE max is 255). 1664 $chunksize = count($chunk); 1665 if ($addunionclause) { 1666 $newsql .= "\n UNION ALL"; 1667 } 1668 $newsql .= "\n SELECT DECODE(pivot"; 1669 $counter = 1; 1670 foreach ($chunk as $element) { 1671 $newsql .= ",\n {$counter}, " . trim($element); 1672 $counter++; 1673 } 1674 $newsql .= ")"; 1675 $newsql .= "\n FROM dual"; 1676 $newsql .= "\n CROSS JOIN (SELECT LEVEL AS pivot FROM dual CONNECT BY LEVEL <= {$chunksize})"; 1677 $addunionclause = true; 1678 } 1679 1680 // Rebuild the complete IN() clause and return it. 1681 return array($instart . $newsql . $inend, $params); 1682 } 1683 1684 /** 1685 * Mega hacky magic to work around crazy Oracle NULL concats. 1686 * @param array $args 1687 * @return string 1688 */ 1689 protected function recursive_concat(array $args) { 1690 $count = count($args); 1691 if ($count == 1) { 1692 $arg = reset($args); 1693 return $arg; 1694 } 1695 if ($count == 2) { 1696 $args[] = "' '"; 1697 // No return here intentionally. 1698 } 1699 $first = array_shift($args); 1700 $second = array_shift($args); 1701 $third = $this->recursive_concat($args); 1702 return "MOODLELIB.TRICONCAT($first, $second, $third)"; 1703 } 1704 1705 /** 1706 * Returns the SQL for returning searching one string for the location of another. 1707 */ 1708 public function sql_position($needle, $haystack) { 1709 return "INSTR(($haystack), ($needle))"; 1710 } 1711 1712 /** 1713 * Returns the SQL to know if one field is empty. 1714 * 1715 * @param string $tablename Name of the table (without prefix). Not used for now but can be 1716 * necessary in the future if we want to use some introspection using 1717 * meta information against the DB. 1718 * @param string $fieldname Name of the field we are going to check 1719 * @param bool $nullablefield For specifying if the field is nullable (true) or no (false) in the DB. 1720 * @param bool $textfield For specifying if it is a text (also called clob) field (true) or a varchar one (false) 1721 * @return string the sql code to be added to check for empty values 1722 */ 1723 public function sql_isempty($tablename, $fieldname, $nullablefield, $textfield) { 1724 if ($textfield) { 1725 return " (".$this->sql_compare_text($fieldname)." = ' ') "; 1726 } else { 1727 return " ($fieldname = ' ') "; 1728 } 1729 } 1730 1731 public function sql_order_by_text($fieldname, $numchars=32) { 1732 return 'dbms_lob.substr(' . $fieldname . ', ' . $numchars . ',1)'; 1733 } 1734 1735 /** 1736 * Is the required OCI server package installed? 1737 * @return bool 1738 */ 1739 protected function oci_package_installed() { 1740 $sql = "SELECT 1 1741 FROM user_objects 1742 WHERE object_type = 'PACKAGE BODY' 1743 AND object_name = 'MOODLELIB' 1744 AND status = 'VALID'"; 1745 $this->query_start($sql, null, SQL_QUERY_AUX); 1746 $stmt = $this->parse_query($sql); 1747 $result = oci_execute($stmt, $this->commit_status); 1748 $this->query_end($result, $stmt); 1749 $records = null; 1750 oci_fetch_all($stmt, $records, 0, -1, OCI_FETCHSTATEMENT_BY_ROW); 1751 oci_free_statement($stmt); 1752 return isset($records[0]) && reset($records[0]) ? true : false; 1753 } 1754 1755 /** 1756 * Try to add required moodle package into oracle server. 1757 */ 1758 protected function attempt_oci_package_install() { 1759 $sqls = file_get_contents(__DIR__.'/oci_native_moodle_package.sql'); 1760 $sqls = preg_split('/^\/$/sm', $sqls); 1761 foreach ($sqls as $sql) { 1762 $sql = trim($sql); 1763 if ($sql === '' or $sql === 'SHOW ERRORS') { 1764 continue; 1765 } 1766 $this->change_database_structure($sql); 1767 } 1768 } 1769 1770 /** 1771 * Does this driver support tool_replace? 1772 * 1773 * @since Moodle 2.8 1774 * @return bool 1775 */ 1776 public function replace_all_text_supported() { 1777 return true; 1778 } 1779 1780 public function session_lock_supported() { 1781 return true; 1782 } 1783 1784 /** 1785 * Obtain session lock 1786 * @param int $rowid id of the row with session record 1787 * @param int $timeout max allowed time to wait for the lock in seconds 1788 * @return void 1789 */ 1790 public function get_session_lock($rowid, $timeout) { 1791 parent::get_session_lock($rowid, $timeout); 1792 1793 $fullname = $this->dbname.'-'.$this->prefix.'-session-'.$rowid; 1794 $sql = 'SELECT MOODLELIB.GET_LOCK(:lockname, :locktimeout) FROM DUAL'; 1795 $params = array('lockname' => $fullname , 'locktimeout' => $timeout); 1796 $this->query_start($sql, $params, SQL_QUERY_AUX); 1797 $stmt = $this->parse_query($sql); 1798 $this->bind_params($stmt, $params); 1799 $result = oci_execute($stmt, $this->commit_status); 1800 if ($result === false) { // Any failure in get_lock() raises error, causing return of bool false 1801 throw new dml_sessionwait_exception(); 1802 } 1803 $this->query_end($result, $stmt); 1804 oci_free_statement($stmt); 1805 } 1806 1807 public function release_session_lock($rowid) { 1808 if (!$this->used_for_db_sessions) { 1809 return; 1810 } 1811 1812 parent::release_session_lock($rowid); 1813 1814 $fullname = $this->dbname.'-'.$this->prefix.'-session-'.$rowid; 1815 $params = array('lockname' => $fullname); 1816 $sql = 'SELECT MOODLELIB.RELEASE_LOCK(:lockname) FROM DUAL'; 1817 $this->query_start($sql, $params, SQL_QUERY_AUX); 1818 $stmt = $this->parse_query($sql); 1819 $this->bind_params($stmt, $params); 1820 $result = oci_execute($stmt, $this->commit_status); 1821 $this->query_end($result, $stmt); 1822 oci_free_statement($stmt); 1823 } 1824 1825 /** 1826 * Driver specific start of real database transaction, 1827 * this can not be used directly in code. 1828 * @return void 1829 */ 1830 protected function begin_transaction() { 1831 $this->commit_status = OCI_DEFAULT; //Done! ;-) 1832 } 1833 1834 /** 1835 * Driver specific commit of real database transaction, 1836 * this can not be used directly in code. 1837 * @return void 1838 */ 1839 protected function commit_transaction() { 1840 $this->query_start('--oracle_commit', NULL, SQL_QUERY_AUX); 1841 $result = oci_commit($this->oci); 1842 $this->commit_status = OCI_COMMIT_ON_SUCCESS; 1843 $this->query_end($result); 1844 } 1845 1846 /** 1847 * Driver specific abort of real database transaction, 1848 * this can not be used directly in code. 1849 * @return void 1850 */ 1851 protected function rollback_transaction() { 1852 $this->query_start('--oracle_rollback', NULL, SQL_QUERY_AUX); 1853 $result = oci_rollback($this->oci); 1854 $this->commit_status = OCI_COMMIT_ON_SUCCESS; 1855 $this->query_end($result); 1856 } 1857 }
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