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This is the Native SQL*Server adapter for the SQL Server Driver for P…

…HP version 1.1 released by Microsoft.

Prerequisites for installation and usage: Install SQL Server 2005 or later, and the SQL Server Driver for PHP version 1.1 (http://msdn.microsoft.com/en-us/library/cc296170(v=SQL.90).aspx), and configure the SQL Server installation using SQL Server Management Studio with the following command:
USE MASTER
GO
ALTER DATABASE <your-database-name> SET READ_COMMITTED_SNAPSHOT ON
GO
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commit 0c57c86713984ab04a239a619d822745d0ace54d 1 parent cd0a2ed
msketcham authored
1,342 lib/dml/sqlsrv_native_moodle_database.php
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@@ -0,0 +1,1342 @@
+<?php
+
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 2 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
+
+/**
+* Native sqlsrv class representing moodle database interface.
+*
+* @package moodlecore
+* @subpackage DML
+* @copyright 2009 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
+* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v2 or later
+*/
+
+require_once($CFG->libdir.'/dml/moodle_database.php');
+require_once($CFG->libdir.'/dml/sqlsrv_native_moodle_recordset.php');
+require_once($CFG->libdir.'/dml/sqlsrv_native_moodle_temptables.php');
+
+/**
+* Native sqlsrv class representing moodle database interface.
+*/
+class sqlsrv_native_moodle_database extends moodle_database {
+
+ protected $sqlsrv = null;
+ protected $last_error_reporting; // To handle SQL*Server-Native driver default verbosity
+ protected $temptables; // Control existing temptables (sqlsrv_moodle_temptables object)
+
+ /**
+ * Contructor - instantiates the database, specifying if it's external (connect to other systems) or no (Moodle DB)
+ * note this has effect to decide if prefix checks must be performed or no
+ * @param bool true means external database used
+ */
+ public function __construct($external=false) {
+ parent::__construct($external);
+ }
+
+ /**
+ * Setup the driver configuration. As a TODO, might want to put some levele of debugging to
+ * see / log more info, warnings, errors.
+ }
+
+ /**
+ * Detects if all needed PHP stuff installed.
+ * Note: can be used before connect()
+ * @return mixed true if ok, string if something
+ */
+ public function driver_installed() {
+ // use 'function_exists()' rather than 'extension_loaded()' because
+ // the name used by 'extension_loaded()' is case specific! The extention
+ // therefor *could be* mixed case and hence not found.
+ if (!function_exists('sqlsrv_num_rows')) {
+ return get_string('sqlsrvextensionisnotpresentinphp', 'install');
+ }
+ return true;
+ }
+
+ /**
+ * Returns database family type - describes SQL dialect
+ * Note: can be used before connect()
+ * @return string db family name (mysql, postgres, mssql, sqlsrv, oracle, etc.)
+ */
+ public function get_dbfamily() {
+ /**
+ * NOTE: If this is changed to use the mssql family of
+ * databases, then sqlsrv_sql_generator.php can be deleted
+ * because it will not be used.
+ */
+ return 'mssql';
+ }
+
+ /**
+ * Returns more specific database driver type
+ * Note: can be used before connect()
+ * @return string db type mysql, pgsql, postgres7, mssql, sqlsrv
+ */
+ protected function get_dbtype() {
+ return 'sqlsrv';
+ }
+
+ /**
+ * Returns general database library name
+ * Note: can be used before connect()
+ * @return string db type pdo, native
+ */
+ protected function get_dblibrary() {
+ return 'native';
+ }
+
+ /**
+ * Returns localised database type name
+ * Note: can be used before connect()
+ * @return string
+ */
+ public function get_name() {
+ return get_string('nativesqlsrv', 'install');
+ }
+
+ /**
+ * Returns localised database configuration help.
+ * Note: can be used before connect()
+ * @return string
+ */
+ public function get_configuration_help() {
+ return get_string('nativesqlsrvhelp', 'install');
+ }
+
+ /**
+ * Returns localised database description
+ * Note: can be used before connect()
+ * @return string
+ */
+ public function get_configuration_hints() {
+ $str = get_string('databasesettingssub_sqlsrv', 'install');
+ $str .= "<p style='text-align:right'><a href=\"javascript:void(0)\" ";
+ $str .= "onclick=\"return window.open('http://docs.moodle.org/en/Installing_sqlsrv_for_PHP')\"";
+ $str .= ">";
+ $str .= '<img src="pix/docs.gif'.'" alt="Docs" class="iconhelp" />';
+ $str .= get_string('moodledocslink', 'install').'</a></p>';
+ return $str;
+ }
+
+ /**
+ * Connect to db
+ * Must be called before other methods.
+ * @param string $dbhost
+ * @param string $dbuser
+ * @param string $dbpass
+ * @param string $dbname
+ * @param mixed $prefix string means moodle db prefix, false used for external databases where prefix not used
+ * @param array $dboptions driver specific options
+ * @return bool true
+ * @throws dml_connection_exception if error
+ */
+ public function connect($dbhost, $dbuser, $dbpass, $dbname, $prefix, array $dboptions=null) {
+ $driverstatus = $this->driver_installed();
+
+ if ($driverstatus !== true) {
+ throw new dml_exception('dbdriverproblem', $driverstatus);
+ }
+
+ /*
+ * Log all Errors.
+ */
+ sqlsrv_configure("WarningsReturnAsErrors", FALSE);
+ sqlsrv_configure("LogSubsystems", SQLSRV_LOG_SYSTEM_ALL);
+ sqlsrv_configure("LogSeverity", SQLSRV_LOG_SEVERITY_ERROR);
+
+ $this->store_settings($dbhost, $dbuser, $dbpass, $dbname, $prefix, $dboptions);
+ $this->sqlsrv = sqlsrv_connect($this->dbhost, array
+ (
+ 'UID' => $this->dbuser,
+ 'PWD' => $this->dbpass,
+ 'Database' => $this->dbname,
+ 'CharacterSet' => 'UTF-8',
+ 'MultipleActiveResultSets' => true,
+ 'ConnectionPooling' => $dboptions['dbpersist'],
+ 'ReturnDatesAsStrings' => true,
+ ));
+
+ if ($this->sqlsrv === false) {
+ $this->sqlsrv = null;
+ $dberr = $this->get_last_error();
+
+ throw new dml_connection_exception($dberr);
+ }
+
+ // Allow quoted identifiers
+ $sql = "SET QUOTED_IDENTIFIER ON";
+ $this->query_start($sql, null, SQL_QUERY_AUX);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+
+ $this->free_result($result);
+
+ // Force ANSI nulls so the NULL check was done by IS NULL and NOT IS NULL
+ // instead of equal(=) and distinct(<>) symbols
+ $sql = "SET ANSI_NULLS ON";
+ $this->query_start($sql, null, SQL_QUERY_AUX);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+
+ $this->free_result($result);
+
+ // Force ANSI warnings so arithmetic/string overflows will be
+ // returning error instead of transparently truncating data
+ $sql = "SET ANSI_WARNINGS ON";
+ $this->query_start($sql, null, SQL_QUERY_AUX);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+
+ // Concatenating null with anything MUST return NULL
+ $sql = "SET CONCAT_NULL_YIELDS_NULL ON";
+ $this->query_start($sql, null, SQL_QUERY_AUX);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+
+ $this->free_result($result);
+
+ // Set transactions isolation level to READ_COMMITTED
+ // prevents dirty reads when using transactions +
+ // is the default isolation level of sqlsrv
+ $sql = "SET TRANSACTION ISOLATION LEVEL READ COMMITTED";
+ $this->query_start($sql, NULL, SQL_QUERY_AUX);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+
+ $this->free_result($result);
+
+ // Connection established and configured, going to instantiate the temptables controller
+ $this->temptables = new sqlsrv_native_moodle_temptables($this);
+
+ return true;
+ }
+
+ /**
+ * Close database connection and release all resources
+ * and memory (especially circular memory references).
+ * Do NOT use connect() again, create a new instance if needed.
+ */
+ public function dispose() {
+ parent::dispose(); // Call parent dispose to write/close session and other common stuff before closing connection
+
+ if ($this->sqlsrv) {
+ sqlsrv_close($this->sqlsrv);
+ $this->sqlsrv = null;
+ }
+ }
+
+ /**
+ * Called before each db query.
+ * @param string $sql
+ * @param array array of parameters
+ * @param int $type type of query
+ * @param mixed $extrainfo driver specific extra information
+ * @return void
+ */
+ protected function query_start($sql, array $params = null, $type, $extrainfo = null) {
+ parent::query_start($sql, $params, $type, $extrainfo);
+ }
+
+ /**
+ * Called immediately after each db query.
+ * @param mixed db specific result
+ * @return void
+ */
+ protected function query_end($result) {
+ parent::query_end($result);
+ }
+
+ /**
+ * Returns database server info array
+ * @return array
+ */
+ public function get_server_info() {
+ static $info;
+
+ if (!$info) {
+ $server_info = sqlsrv_server_info($this->sqlsrv);
+
+ if ($server_info) {
+ $info['server'] = $server_info['SQLServerName'];
+ $info['version'] = $server_info['SQLServerVersion'];
+ $info['database'] = $server_info['CurrentDatabase'];
+ }
+ }
+ return $info;
+ }
+
+ /**
+ * Get the minimum SQL allowed
+ *
+ * @param mixed $version
+ * @return mixed
+ */
+ protected function is_min_version($version) {
+ $server = $this->get_server_info();
+ $server = $server['version'];
+ return version_compare($server, $version, '>=');
+ }
+
+ /**
+ * Override: Converts short table name {tablename} to real table name
+ * supporting temp tables (#) if detected
+ *
+ * @param string sql
+ * @return string sql
+ */
+ protected function fix_table_names($sql) {
+ if (preg_match_all('/\{([a-z][a-z0-9_]*)\}/i', $sql, $matches)) {
+ foreach ($matches[0] as $key => $match) {
+ $name = $matches[1][$key];
+
+ if ($this->temptables->is_temptable($name)) {
+ $sql = str_replace($match, $this->temptables->get_correct_name($name), $sql);
+ } else {
+ $sql = str_replace($match, $this->prefix.$name, $sql);
+ }
+ }
+ }
+ return $sql;
+ }
+
+ /**
+ * Returns supported query parameter types
+ * @return bitmask
+ */
+ protected function allowed_param_types() {
+ return SQL_PARAMS_QM; // sqlsrv 1.1 can bind
+ }
+
+ /**
+ * Returns last error reported by database engine.
+ */
+ public function get_last_error() {
+ $retErrors = sqlsrv_errors(SQLSRV_ERR_ALL);
+ $errorMessage = 'No errors found';
+
+ if ($retErrors != null) {
+ $errorMessage = '';
+
+ foreach ($retErrors as $arrError) {
+ $errorMessage .= "SQLState: ".$arrError['SQLSTATE']."<br>\n";
+ $errorMessage .= "Error Code: ".$arrError['code']."<br>\n";
+ $errorMessage .= "Message: ".$arrError['message']."<br>\n";
+ }
+ }
+
+ return $errorMessage;
+ }
+
+ /***
+ * Bound variables *are* supported. Until I can get it to work, emulate the bindings
+ * The challenge/problem/bug is that allthough they work, doing a SELECT SCOPE_IDENTITY()
+ * doesnt return a value (no result set)
+ */
+
+ /**
+ * Prepare the query binding and do the actual query.
+ *
+ * @param string $sql The sql statment
+ * @param mixed $params array of params for binding. If NULL, they are ignored.
+ * @param mixed $sql_query_type - Type of operation
+ * @param mixed $free_result - Default true, transaction query will be freed.
+ */
+ private function do_query($sql, $params, $sql_query_type, $free_result = true) {
+ list($sql, $params, $type) = $this->fix_sql_params($sql, $params);
+
+ $sql = $this->emulate_bound_params($sql, $params);
+ $this->query_start($sql, $params, $sql_query_type);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+
+ if ($result === false) {
+ // TODO do something with error or just use if DEV or DEBUG?
+ $dberr = $this->get_last_error();
+ }
+
+ $this->query_end($result);
+
+ if ($free_result) {
+ $this->free_result($result);
+ return true;
+ }
+ return $result;
+ }
+
+ /**
+ * Return tables in database WITHOUT current prefix
+ * @return array of table names in lowercase and without prefix
+ */
+ public function get_tables($usecache = true) {
+ if ($usecache and count($this->tables) > 0) {
+ return $this->tables;
+ }
+ $this->tables = array ();
+ $sql = "SELECT table_name ".
+ "FROM information_schema.tables ".
+ "WHERE table_name LIKE '$this->prefix%' ".
+ "AND table_type = 'BASE TABLE'";
+
+ $this->query_start($sql, null, SQL_QUERY_AUX);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+
+ if ($result) {
+ while ($row = sqlsrv_fetch_array($result)) {
+ $tablename = reset($row);
+ if (strpos($tablename, $this->prefix) !== 0) {
+ continue;
+ }
+ $tablename = substr($tablename, strlen($this->prefix));
+ $this->tables[$tablename] = $tablename;
+ }
+ $this->free_result($result);
+ }
+
+ // Add the currently available temptables
+ $this->tables = array_merge($this->tables, $this->temptables->get_temptables());
+ return $this->tables;
+ }
+
+ /**
+ * Return table indexes - everything lowercased
+ * @return array of arrays
+ */
+ public function get_indexes($table) {
+ $indexes = array ();
+ $tablename = $this->prefix.$table;
+
+ // Indexes aren't covered by information_schema metatables, so we need to
+ // go to sys ones. Skipping primary key indexes on purpose.
+ $sql = "SELECT i.name AS index_name, i.is_unique, ic.index_column_id, c.name AS column_name
+ FROM sys.indexes i
+ JOIN sys.index_columns ic ON i.object_id = ic.object_id AND i.index_id = ic.index_id
+ JOIN sys.columns c ON ic.object_id = c.object_id AND ic.column_id = c.column_id
+ JOIN sys.tables t ON i.object_id = t.object_id
+ WHERE t.name = '$tablename'
+ AND i.is_primary_key = 0
+ ORDER BY i.name, i.index_id, ic.index_column_id";
+
+ $this->query_start($sql, null, SQL_QUERY_AUX);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+
+ if ($result) {
+ $lastindex = '';
+ $unique = false;
+ $columns = array ();
+
+ while ($row = sqlsrv_fetch_array($result, SQLSRV_FETCH_ASSOC)) {
+ if ($lastindex and $lastindex != $row['index_name'])
+ { // Save lastindex to $indexes and reset info
+ $indexes[$lastindex] = array
+ (
+ 'unique' => $unique,
+ 'columns' => $columns
+ );
+
+ $unique = false;
+ $columns = array ();
+ }
+ $lastindex = $row['index_name'];
+ $unique = empty($row['is_unique']) ? false : true;
+ $columns[] = $row['column_name'];
+ }
+
+ if ($lastindex) { // Add the last one if exists
+ $indexes[$lastindex] = array
+ (
+ 'unique' => $unique,
+ 'columns' => $columns
+ );
+ }
+
+ $this->free_result($result);
+ }
+ return $indexes;
+ }
+
+ /**
+ * Returns datailed information about columns in table. This information is cached internally.
+ * @param string $table name
+ * @param bool $usecache
+ * @return array array of database_column_info objects indexed with column names
+ */
+ public function get_columns($table, $usecache = true) {
+ if ($usecache and isset($this->columns[$table])) {
+ return $this->columns[$table];
+ }
+
+ $this->columns[$table] = array ();
+
+ if (!$this->temptables->is_temptable($table)) { // normal table, get metadata from own schema
+ $sql = "SELECT column_name AS name,
+ data_type AS type,
+ numeric_precision AS max_length,
+ character_maximum_length AS char_max_length,
+ numeric_scale AS scale,
+ is_nullable AS is_nullable,
+ columnproperty(object_id(quotename(table_schema) + '.' +
+ quotename(table_name)), column_name, 'IsIdentity') AS auto_increment,
+ column_default AS default_value
+ FROM information_schema.columns
+ WHERE table_name = '{".$table."}'
+ ORDER BY ordinal_position";
+ } else { // temp table, get metadata from tempdb schema
+ $sql = "SELECT column_name AS name,
+ data_type AS type,
+ numeric_precision AS max_length,
+ character_maximum_length AS char_max_length,
+ numeric_scale AS scale,
+ is_nullable AS is_nullable,
+ columnproperty(object_id(quotename(table_schema) + '.' +
+ quotename(table_name)), column_name, 'IsIdentity') AS auto_increment,
+ column_default AS default_value
+ FROM tempdb.information_schema.columns ".
+ // check this statement
+ // JOIN tempdb..sysobjects ON name = table_name
+ // WHERE id = object_id('tempdb..{".$table."}')
+ "WHERE table_name like '{".$table."}__________%'
+ ORDER BY ordinal_position";
+ }
+
+ list($sql, $params, $type) = $this->fix_sql_params($sql, null);
+
+ $this->query_start($sql, null, SQL_QUERY_AUX);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+
+ if (!$result) {
+ return array ();
+ }
+
+ while ($rawcolumn = sqlsrv_fetch_array($result, SQLSRV_FETCH_ASSOC)) {
+
+ $rawcolumn = (object)$rawcolumn;
+
+ $info = new object();
+ $info->name = $rawcolumn->name;
+ $info->type = $rawcolumn->type;
+ $info->meta_type = $this->sqlsrvtype2moodletype($info->type);
+
+ // Prepare auto_increment info
+ $info->auto_increment = $rawcolumn->auto_increment ? true : false;
+
+ // Define type for auto_increment columns
+ $info->meta_type = ($info->auto_increment && $info->meta_type == 'I') ? 'R' : $info->meta_type;
+
+ // id columns being auto_incremnt are PK by definition
+ $info->primary_key = ($info->name == 'id' && $info->meta_type == 'R' && $info->auto_increment);
+
+ // Put correct length for character and LOB types
+ $info->max_length = $info->meta_type == 'C' ? $rawcolumn->char_max_length : $rawcolumn->max_length;
+ $info->max_length = ($info->meta_type == 'X' || $info->meta_type == 'B') ? -1 : $info->max_length;
+
+ // Scale
+ $info->scale = $rawcolumn->scale ? $rawcolumn->scale : false;
+
+ // Prepare not_null info
+ $info->not_null = $rawcolumn->is_nullable == 'NO' ? true : false;
+
+ // Process defaults
+ $info->has_default = !empty($rawcolumn->default_value);
+ $info->default_value = preg_replace("/^[\(N]+[']?(.*?)[']?[\)]+$/", '\\1', $rawcolumn->default_value);
+
+ // Process binary
+ $info->binary = $info->meta_type == 'B' ? true : false;
+
+ $this->columns[$table][$info->name] = new database_column_info($info);
+ }
+ $this->free_result($result);
+
+ return $this->columns[$table];
+ }
+
+ /**
+ * Normalise values based in RDBMS dependencies (booleans, LOBs...)
+ *
+ * @param database_column_info $column column metadata corresponding with the value we are going to normalise
+ * @param mixed $value value we are going to normalise
+ * @return mixed the normalised value
+ */
+ protected function normalise_value($column, $value) {
+ if (is_bool($value)) { /// Always, convert boolean to int
+ $value = (int)$value;
+ } // And continue processing because text columns with numeric info need special handling below
+
+ if ($column->meta_type == 'B')
+ { // BLOBs need to be properly "packed", but can be inserted directly if so.
+ if (!is_null($value)) { // If value not null, unpack it to unquoted hexadecimal byte-string format
+ $value = unpack('H*hex', $value); // we leave it as array, so emulate_bound_params() can detect it
+ } // easily and "bind" the param ok.
+
+ } else if ($column->meta_type == 'X') { // sqlsrv doesn't cast from int to text, so if text column
+ if (is_numeric($value)) { // and is numeric value then cast to string
+ $value = array('numstr' => (string)$value); // and put into array, so emulate_bound_params() will know how
+ } // to "bind" the param ok, avoiding reverse conversion to number
+ } else if ($value === '') {
+
+ if ($column->meta_type == 'I' or $column->meta_type == 'F' or $column->meta_type == 'N') {
+ $value = 0; // prevent '' problems in numeric fields
+ }
+ }
+ return $value;
+ }
+
+ /**
+ * Selectively call sqlsrv_free_stmt(), avoiding some warnings without using the horrible @
+ *
+ * @param sqlsrv_resource $resource resource to be freed if possible
+ */
+ private function free_result($resource) {
+ if (!is_bool($resource)) { // true/false resources cannot be freed
+ return sqlsrv_free_stmt($resource);
+ }
+ }
+
+ /**
+ * Provides mapping between sqlsrv native data types and moodle_database - database_column_info - ones)
+ *
+ * @param string $sqlsrv_type native sqlsrv data type
+ * @return string 1-char database_column_info data type
+ */
+ private function sqlsrvtype2moodletype($sqlsrv_type) {
+ $type = null;
+
+ switch (strtoupper($sqlsrv_type)) {
+ case 'BIT':
+ $type = 'L';
+ break;
+
+ case 'INT':
+ case 'SMALLINT':
+ case 'INTEGER':
+ case 'BIGINT':
+ $type = 'I';
+ break;
+
+ case 'DECIMAL':
+ case 'REAL':
+ case 'FLOAT':
+ $type = 'N';
+ break;
+
+ case 'VARCHAR':
+ case 'NVARCHAR':
+ $type = 'C';
+ break;
+
+ case 'TEXT':
+ case 'NTEXT':
+ case 'VARCHAR(MAX)':
+ case 'NVARCHAR(MAX)':
+ $type = 'X';
+ break;
+
+ case 'IMAGE':
+ case 'VARBINARY(MAX)':
+ $type = 'B';
+ break;
+
+ case 'DATETIME':
+ $type = 'D';
+ break;
+ }
+
+ if (!$type) {
+ throw new dml_exception('invalidsqlsrvnativetype', $sqlsrv_type);
+ }
+ return $type;
+ }
+
+ /**
+ * Do NOT use in code, to be used by database_manager only!
+ * @param string $sql query
+ * @return bool true
+ * @throws dml_exception if error
+ */
+ public function change_database_structure($sql) {
+ $this->reset_caches();
+
+ $this->query_start($sql, null, SQL_QUERY_STRUCTURE);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+
+ return true;
+ }
+
+ /**
+ * Prepare the array of params for native binding
+ */
+ protected function build_native_bound_params(array $params = null) {
+
+ return null;
+ }
+
+
+ /**
+ * Workaround for SQL*Server Native driver similar to MSSQL driver for
+ * consistent behavior.
+ */
+ protected function emulate_bound_params($sql, array $params = null) {
+
+ if (empty($params)) {
+ return $sql;
+ }
+ /// ok, we have verified sql statement with ? and correct number of params
+ $return = strtok($sql, '?');
+
+ foreach ($params as $param) {
+ if (is_bool($param)) {
+ $return .= (int)$param;
+ } else if (is_array($param) && isset($param['hex'])) { // detect hex binary, bind it specially
+ $return .= '0x'.$param['hex'];
+ } else if (is_array($param) && isset($param['numstr'])) { // detect numerical strings that *must not*
+ $return .= "N'{$param['numstr']}'"; // be converted back to number params, but bound as strings
+ } else if (is_null($param)) {
+ $return .= 'NULL';
+
+ } else if ($this->is_number($param)) { // we can not use is_numeric() because it eats leading zeros from strings like 0045646
+ $return .= $param;
+ } else if (is_float($param)) {
+ $return .= $param;
+ } else {
+ $param = str_replace("'", "''", $param);
+ $return .= "N'$param'";
+ }
+
+ $return .= strtok('?');
+ }
+ return $return;
+ }
+
+ /* this function exists in modlib, so i would need to include that..
+ */
+ /**
+ * Return true if given value is integer or string with integer value
+ *
+ * @param mixed $value String or Int
+ * @return bool true if number, false if not
+ */
+ private static function is_number($value) {
+ if (is_int($value)) {
+ return true;
+ } else if (is_string($value)) {
+ return ((string)(int)$value) === $value;
+ } else {
+ return false;
+ }
+ }
+
+ /**
+ * Execute general sql query. Should be used only when no other method suitable.
+ * Do NOT use this to make changes in db structure, use database_manager::execute_sql() instead!
+ * @param string $sql query
+ * @param array $params query parameters
+ * @return bool true
+ * @throws dml_exception if error
+ */
+ public function execute($sql, array $params = null) {
+ if (strpos($sql, ';') !== false) {
+ throw new coding_exception('moodle_database::execute() Multiple sql statements found or bound parameters not used properly in query!');
+ }
+ $this->do_query($sql, $params, SQL_QUERY_UPDATE);
+ return true;
+ }
+
+ /**
+ * Get a number of records as a moodle_recordset using a SQL statement.
+ *
+ * Since this method is a little less readable, use of it should be restricted to
+ * code where it's possible there might be large datasets being returned. For known
+ * small datasets use get_records_sql - it leads to simpler code.
+ *
+ * The return type is as for @see function get_recordset.
+ *
+ * @param string $sql the SQL select query to execute.
+ * @param array $params array of sql parameters
+ * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
+ * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
+ * @return mixed an moodle_recordset object
+ * @throws dml_exception if error
+ */
+ public function get_recordset_sql($sql, array $params = null, $limitfrom = 0, $limitnum = 0) {
+ $limitfrom = (int)$limitfrom;
+ $limitnum = (int)$limitnum;
+ $limitfrom = max(0, $limitfrom);
+ $limitnum = max(0, $limitnum);
+
+ if ($limitfrom or $limitnum) {
+ $sql = $this->limit_to_top_n($sql, $limitfrom, $limitnum);
+ }
+ $result = $this->do_query($sql, $params, SQL_QUERY_SELECT, false);
+ return $this->create_recordset($result);
+ }
+
+ /**
+ * Preform a emulation for LIMIT(offset, limit)
+ *
+ * @param mixed $sql
+ * @param mixed $offset
+ * @param mixed $limit
+ * @return mixed
+ */
+ private function limit_to_top_n($sql, $offset, $limit) {
+ if ($limit < 1 && $offset < 1) {
+ return $sql;
+ }
+ $limit = max(0, $limit);
+ $offset = max(0, $offset);
+
+ if ($limit > 0 && $offset == 0) {
+ $sql1 = preg_replace('/^([\s(])*SELECT( DISTINCT | ALL)?(?!\s*TOP\s*\()/i',
+ "\\1SELECT\\2 TOP $limit", $sql);
+ } else {
+ // Only apply TOP clause if we have any limitnum (limitfrom offset is hadled later)
+ if ($limit < 1) {
+ $limit = "9223372036854775806"; // MAX BIGINT -1
+ }
+ if (preg_match('/\w*FROM[\s|{]*([\w|.]*)[\s|}]?/i', $sql, $match)) {
+ $from_table = $match[1];
+ if (preg_match('/SELECT[\w|\s]*(\*)[\w|\s]*FROM/i', $sql)) {
+ // Need all the columns as the emulation returns some temp cols
+ $cols = array_keys($this->get_columns($from_table));
+ $cols = implode(', ', $cols);
+ } else {
+ $cols = '*';
+ }
+ $sql1 = 'SELECT '.$cols.' FROM ( '
+ .'SELECT sub2.*, ROW_NUMBER() OVER(ORDER BY sub2.line2) AS line3 FROM ( '
+ .'SELECT 1 AS line2, sub1.* FROM '
+ .'{'.$from_table.'} AS sub1 '
+ .') AS sub2 '
+ .') AS sub3 '
+ .'WHERE line3 BETWEEN '.($offset+1).' AND '
+ .($offset + $limit);
+ } else {
+ $sql1 = "SELECT 'Invalid table'";
+ }
+ }
+
+ return $sql1;
+ }
+
+ /**
+ * Create a record set and initialize with first row
+ *
+ * @param mixed $result
+ * @return sqlsrv_native_moodle_recordset
+ */
+ protected function create_recordset($result) {
+ return new sqlsrv_native_moodle_recordset($result);
+ }
+
+ /**
+ * Get a number of records as an array of objects using a SQL statement.
+ *
+ * Return value as for @see function get_records.
+ *
+ * @param string $sql the SQL select query to execute. The first column of this SELECT statement
+ * must be a unique value (usually the 'id' field), as it will be used as the key of the
+ * returned array.
+ * @param array $params array of sql parameters
+ * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
+ * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
+ * @return mixed an array of objects, or empty array if no records were found
+ * @throws dml_exception if error
+ */
+ public function get_records_sql($sql, array $params = null, $limitfrom = 0, $limitnum = 0) {
+
+ $rs = $this->get_recordset_sql($sql, $params, $limitfrom, $limitnum);
+
+ $results = array();
+
+ foreach ($rs as $row) {
+ $id = reset($row);
+
+ if (isset($return[$id])) {
+ $colname = key($row);
+ 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);
+ }
+ $results[$id] = (object)$row;
+ }
+ $rs->close();
+
+ return $results;
+ }
+
+ /**
+ * Selects records and return values (first field) as an array using a SQL statement.
+ *
+ * @param string $sql The SQL query
+ * @param array $params array of sql parameters
+ * @return mixed array of values
+ * @throws dml_exception if error
+ */
+ public function get_fieldset_sql($sql, array $params = null) {
+
+ $rs = $this->get_recordset_sql($sql, $params);
+
+ $results = array ();
+
+ foreach ($rs as $row) {
+ $results[] = reset($row);
+ }
+ $rs->close();
+
+ return $results;
+ }
+
+ /**
+ * Insert new record into database, as fast as possible, no safety checks, lobs not supported.
+ * @param string $table name
+ * @param mixed $params data record as object or array
+ * @param bool $returnit return it of inserted record
+ * @param bool $bulk true means repeated inserts expected
+ * @param bool $customsequence true if 'id' included in $params, disables $returnid
+ * @return true or new id
+ * @throws dml_exception if error
+ */
+ public function insert_record_raw($table, $params, $returnid=true, $bulk=false, $customsequence=false) {
+ if (!is_array($params)) {
+ $params = (array)$params;
+ }
+ if ($customsequence) {
+ if (!isset($params['id'])) {
+ throw new coding_exception('moodle_database::insert_record_raw() id field must be specified if custom sequences used.');
+ }
+ $returnid = false;
+ } else {
+ unset($params['id']);
+ }
+
+ if (empty($params)) {
+ throw new coding_exception('moodle_database::insert_record_raw() no fields found.');
+ }
+ $fields = implode(',', array_keys($params));
+ $qms = array_fill(0, count($params), '?');
+ $qms = implode(',', $qms);
+ $sql = "INSERT INTO {" . $table . "} ($fields) VALUES($qms)";
+ $query_id = $this->do_query($sql, $params, SQL_QUERY_INSERT);
+ if ($returnid) {
+ $id = $this->sqlsrv_fetch_id();
+ return $id;
+ } else {
+ return true;
+ }
+ }
+
+ /**
+ * Get the ID of the current action
+ *
+ * @return mixed ID
+ */
+ private function sqlsrv_fetch_id() {
+ $query_id = sqlsrv_query($this->sqlsrv, 'SELECT SCOPE_IDENTITY()');
+ if ($query_id === false) {
+ $dberr = $this->get_last_error();
+ return false;
+ }
+ $row = $this->sqlsrv_fetchrow($query_id);
+ return (int)$row[0];
+ }
+
+ /**
+ * Fetch a single row into an numbered array
+ *
+ * @param mixed $query_id
+ */
+ private function sqlsrv_fetchrow($query_id) {
+ $row = sqlsrv_fetch_array($query_id, SQLSRV_FETCH_NUMERIC);
+ if ($row === false) {
+ $dberr = $this->get_last_error();
+ return false;
+ }
+
+ foreach ($row as $key => $value) {
+ $row[$key] = ($value === ' ' || $value === NULL) ? '' : $value;
+ }
+ return $row;
+ }
+
+ /**
+ * Insert a record into a table and return the "id" field if required.
+ *
+ * Some conversions and safety checks are carried out. Lobs are supported.
+ * If the return ID isn't required, then this just reports success as true/false.
+ * $data is an object containing needed data
+ * @param string $table The database table to be inserted into
+ * @param object $data A data object with values for one or more fields in the record
+ * @param bool $returnid Should the id of the newly created record entry be returned? If this option is not requested then true/false is returned.
+ * @return true or new id
+ * @throws dml_exception if error
+ */
+ public function insert_record($table, $dataobject, $returnid = true, $bulk = false) {
+ if (!is_object($dataobject)) {
+ $dataobject = (object)$dataobject;
+ }
+
+ unset($dataobject->id);
+
+ $columns = $this->get_columns($table);
+ $cleaned = array ();
+
+ foreach ($dataobject as $field => $value) {
+ if (!isset($columns[$field])) {
+ continue;
+ }
+ $column = $columns[$field];
+ $cleaned[$field] = $this->normalise_value($column, $value);
+ }
+
+ return $this->insert_record_raw($table, $cleaned, $returnid, $bulk);
+ }
+
+ /**
+ * Import a record into a table, id field is required.
+ * Safety checks are NOT carried out. Lobs are supported.
+ *
+ * @param string $table name of database table to be inserted into
+ * @param object $dataobject A data object with values for one or more fields in the record
+ * @return bool true
+ * @throws dml_exception if error
+ */
+ public function import_record($table, $dataobject) {
+ if (!is_object($dataobject)) {
+ $dataobject = (object)$dataobject;
+ }
+
+ $columns = $this->get_columns($table);
+ $cleaned = array ();
+
+ foreach ($dataobject as $field => $value) {
+ if (!isset($columns[$field])) {
+ continue;
+ }
+ $column = $columns[$field];
+ $cleaned[$field] = $this->normalise_value($column, $value);
+ }
+
+ // Disable IDENTITY column before inserting record with id
+ $sql = 'SET IDENTITY_INSERT {'.$table.'} ON'; // Yes, it' ON!!
+ $this->do_query($sql, null, SQL_QUERY_AUX);
+
+ $insertresult = $this->insert_record_raw($table, $cleaned, false, false, true);
+
+ // Enable IDENTITY column after inserting record with id
+ $sql = 'SET IDENTITY_INSERT {'.$table.'} OFF'; // Yes, it' OFF!!
+
+ $this->do_query($sql, null, SQL_QUERY_AUX);
+
+ return $insertresult;
+ }
+
+ /**
+ * Update record in database, as fast as possible, no safety checks, lobs not supported.
+ * @param string $table name
+ * @param mixed $params data record as object or array
+ * @param bool true means repeated updates expected
+ * @return bool true
+ * @throws dml_exception if error
+ */
+ public function update_record_raw($table, $params, $bulk = false) {
+ if (!is_array($params)) {
+ $params = (array)$params;
+ }
+
+ if (!isset($params['id'])) {
+ throw new coding_exception('moodle_database::update_record_raw() id field must be specified.');
+ }
+ $id = $params['id'];
+ unset($params['id']);
+
+ if (empty($params)) {
+ throw new coding_exception('moodle_database::update_record_raw() no fields found.');
+ }
+
+ $sets = array ();
+
+ foreach ($params as $field => $value) {
+ $sets[] = "$field = ?";
+ }
+
+ $params[] = $id; // last ? in WHERE condition
+
+ $sets = implode(',', $sets);
+ $sql = "UPDATE {".$table."} SET $sets WHERE id = ?";
+
+ $this->do_query($sql, $params, SQL_QUERY_UPDATE);
+
+ return true;
+ }
+
+ /**
+ * Update a record in a table
+ *
+ * $dataobject is an object containing needed data
+ * Relies on $dataobject having a variable "id" to
+ * specify the record to update
+ *
+ * @param string $table The database table to be checked against.
+ * @param object $dataobject An object with contents equal to fieldname=>fieldvalue. Must have an entry for 'id' to map to the table specified.
+ * @param bool true means repeated updates expected
+ * @return bool true
+ * @throws dml_exception if error
+ */
+ public function update_record($table, $dataobject, $bulk = false) {
+ if (!is_object($dataobject)) {
+ $dataobject = (object)$dataobject;
+ }
+
+ $columns = $this->get_columns($table);
+ $cleaned = array ();
+
+ foreach ($dataobject as $field => $value) {
+ if (!isset($columns[$field])) {
+ continue;
+ }
+ $column = $columns[$field];
+ $cleaned[$field] = $this->normalise_value($column, $value);
+ }
+
+ return $this->update_record_raw($table, $cleaned, $bulk);
+ }
+
+ /**
+ * Set a single field in every table record which match a particular WHERE clause.
+ *
+ * @param string $table The database table to be checked against.
+ * @param string $newfield the field to set.
+ * @param string $newvalue the value to set the field to.
+ * @param string $select A fragment of SQL to be used in a where clause in the SQL call.
+ * @param array $params array of sql parameters
+ * @return bool true
+ * @throws dml_exception if error
+ */
+ public function set_field_select($table, $newfield, $newvalue, $select, array $params = null) {
+ if ($select) {
+ $select = "WHERE $select";
+ }
+
+ if (is_null($params)) {
+ $params = array ();
+ }
+
+ /// Get column metadata
+ $columns = $this->get_columns($table);
+ $column = $columns[$newfield];
+
+ $newvalue = $this->normalise_value($column, $newvalue);
+
+ if (is_null($newvalue)) {
+ $newfield = "$newfield = NULL";
+ } else {
+ $newfield = "$newfield = ?";
+ array_unshift($params, $newvalue);
+ }
+ $sql = "UPDATE {".$table."} SET $newfield $select";
+
+ $this->do_query($sql, $params, SQL_QUERY_UPDATE);
+
+ return true;
+ }
+
+ /**
+ * Delete one or more records from a table which match a particular WHERE clause.
+ *
+ * @param string $table The database table to be checked against.
+ * @param string $select A fragment of SQL to be used in a where clause in the SQL call (used to define the selection criteria).
+ * @param array $params array of sql parameters
+ * @return bool true
+ * @throws dml_exception if error
+ */
+ public function delete_records_select($table, $select, array $params = null) {
+ if ($select) {
+ $select = "WHERE $select";
+ }
+
+ $sql = "DELETE FROM {".$table."} $select";
+
+ $this->do_query($sql, $params, SQL_QUERY_UPDATE); // msk probably should be SQL_QUERY_DELETE
+
+ return true;
+ }
+
+
+ /// SQL helper functions
+
+ public function sql_bitxor($int1, $int2) {
+ return '('.$this->sql_bitor($int1, $int2).' - '.$this->sql_bitand($int1, $int2).')';
+ }
+
+ public function sql_cast_char2int($fieldname, $text = false) {
+ return ' CAST('.$fieldname.' AS INT) ';
+ }
+
+ public function sql_ceil($fieldname) {
+ return ' CEILING('.$fieldname.')';
+ }
+
+ public function sql_concat() {
+ $arr = func_get_args();
+
+ foreach ($arr as $key => $ele) {
+ $arr[$key] = ' CAST('.$ele.' AS VARCHAR(255)) ';
+ }
+ $s = implode(' + ', $arr);
+
+ if ($s === '') {
+ return " '' ";
+ }
+ return " $s ";
+ }
+
+ public function sql_concat_join($separator = "' '", $elements = array ()) {
+ for ($n = count($elements) - 1; $n > 0; $n--) {
+ array_splice($elements, $n, 0, $separator);
+ }
+ $s = implode(' + ', $elements);
+
+ if ($s === '') {
+ return " '' ";
+ }
+ return " $s ";
+ }
+
+ public function sql_isempty($tablename, $fieldname, $nullablefield, $textfield) {
+ if ($textfield) {
+ return ' ('.$this->sql_compare_text($fieldname)." = '') ";
+ } else {
+ return " ($fieldname = '') ";
+ }
+ }
+
+ /**
+ * Returns the SQL text to be used to calculate the length in characters of one expression.
+ * @param string fieldname or expression to calculate its length in characters.
+ * @return string the piece of SQL code to be used in the statement.
+ */
+ public function sql_length($fieldname) {
+ return ' LEN('.$fieldname.')';
+ }
+
+ public function sql_order_by_text($fieldname, $numchars = 32) {
+ return ' CONVERT(varchar, '.$fieldname.', '.$numchars.')';
+ }
+
+ /**
+ * Returns the SQL for returning searching one string for the location of another.
+ */
+ public function sql_position($needle, $haystack) {
+ return "CHARINDEX(($needle), ($haystack))";
+ }
+
+ /**
+ * Returns the proper substr() SQL text used to extract substrings from DB
+ * NOTE: this was originally returning only function name
+ *
+ * @param string $expr some string field, no aggregates
+ * @param mixed $start integer or expresion evaluating to int
+ * @param mixed $length optional integer or expresion evaluating to int
+ * @return string sql fragment
+ */
+ public function sql_substr($expr, $start, $length = false) {
+ if (count(func_get_args()) < 2) {
+ throw new coding_exception('moodle_database::sql_substr() requires at least two parameters', 'Originaly this function wa
+ s only returning name of SQL substring function, it now requires all parameters.');
+ }
+
+ if ($length === false) {
+ return "SUBSTRING($expr, $start, (LEN($expr) - $start + 1))";
+ } else {
+ return "SUBSTRING($expr, $start, $length)";
+ }
+ }
+
+ /// session locking
+
+ public function session_lock_supported() {
+ return true;
+ }
+
+ public function get_session_lock($rowid) {
+ if (!$this->session_lock_supported()) {
+ return;
+ }
+ parent::get_session_lock($rowid);
+
+ $fullname = $this->dbname.'-'.$this->prefix.'-session-'.$rowid;
+ $sql = "sp_getapplock '$fullname', 'Exclusive', 'Session', 120000";
+ $this->query_start($sql, null, SQL_QUERY_AUX);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+ $this->free_result($result);
+ }
+
+ public function release_session_lock($rowid) {
+ if (!$this->session_lock_supported()) {
+ return;
+ }
+ parent::release_session_lock($rowid);
+
+ $fullname = $this->dbname.'-'.$this->prefix.'-session-'.$rowid;
+ $sql = "sp_releaseapplock '$fullname', 'Session'";
+ $this->query_start($sql, null, SQL_QUERY_AUX);
+ $result = sqlsrv_query($this->sqlsrv, $sql);
+ $this->query_end($result);
+ $this->free_result($result);
+ }
+
+
+ /// transactions
+
+ // NOTE:
+ // TODO -- should these be wrapped in query start/end? They arnt a query
+ // but information and error capture is nice. msk
+
+
+ /**
+ * Driver specific start of real database transaction,
+ * this can not be used directly in code.
+ * @return void
+ */
+ protected function begin_transaction() {
+ $this->query_start('native sqlsrv_begin_transaction', NULL, SQL_QUERY_AUX);
+ $result = sqlsrv_begin_transaction($this->sqlsrv);
+ $this->query_end($result);
+ }
+
+ /**
+ * Driver specific commit of real database transaction,
+ * this can not be used directly in code.
+ * @return void
+ */
+ protected function commit_transaction() {
+ $this->query_start('native sqlsrv_commit', NULL, SQL_QUERY_AUX);
+ $result = sqlsrv_commit($this->sqlsrv);
+ $this->query_end($result);
+ }
+
+ /**
+ * Driver specific abort of real database transaction,
+ * this can not be used directly in code.
+ * @return void
+ */
+ protected function rollback_transaction() {
+ $this->query_start('native sqlsrv_rollback', NULL, SQL_QUERY_AUX);
+ $result = sqlsrv_rollback($this->sqlsrv);
+ $this->query_end($result);
+ }
+}
78 lib/dml/sqlsrv_native_moodle_recordset.php
View
@@ -0,0 +1,78 @@
+<?php
+
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 2 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
+
+/**
+* sqlsrv specific recorset.
+*
+* @package moodlecore
+* @subpackage DML
+* @copyright 2009 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
+* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v2 or later
+*/
+
+require_once($CFG->libdir.'/dml/moodle_recordset.php');
+
+class sqlsrv_native_moodle_recordset extends moodle_recordset {
+
+ protected $rsrc;
+ protected $current;
+
+ public function __construct($rsrc) {
+ $this->rsrc = $rsrc;
+ $this->current = $this->fetch_next();
+ }
+
+ public function __destruct() {
+ $this->close();
+ }
+
+ private function fetch_next() {
+ if ($row = sqlsrv_fetch_array($this->rsrc, SQLSRV_FETCH_ASSOC)) {
+ $row = array_change_key_case($row, CASE_LOWER);
+ }
+ return $row;
+ }
+
+ public function current() {
+ return (object)$this->current;
+ }
+
+ public function key() {
+ /// return first column value as key
+ if (!$this->current) {
+ return false;
+ }
+ $key = reset($this->current);
+ return $key;
+ }
+
+ public function next() {
+ $this->current = $this->fetch_next();
+ }
+
+ public function valid() {
+ return !empty($this->current);
+ }
+
+ public function close() {
+ if ($this->rsrc) {
+ sqlsrv_free_stmt($this->rsrc);
+ $this->rsrc = null;
+ }
+ $this->current = null;
+ }
+}
35 lib/dml/sqlsrv_native_moodle_temptables.php
View
@@ -0,0 +1,35 @@
+<?php
+
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 2 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
+
+/**
+* sqlsrv specific temptables store. Needed because temporary tables
+* are named diferently than normal tables. Also used to be able to retrieve
+* temp table names included in the get_tables() method od the DB.
+*
+* @package moodlecore
+* @subpackage DML
+* @copyright 2009 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
+* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v2 or later
+*/
+
+require_once($CFG->libdir.'/dml/mssql_native_moodle_temptables.php');
+
+/***
+* This class is not specific to the SQL Server Native Driver but rather
+* to the family of Microsoft SQL Servers
+*/
+class sqlsrv_native_moodle_temptables extends mssql_native_moodle_temptables {}
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