Proyectos de Subversion Moodle

<?php

/**

 * Native MSSQL driver.

 *

 * Requires mssql client. Works on Windows.

 * https://docs.microsoft.com/sql/connect/php

 *

 * This file is part of ADOdb, a Database Abstraction Layer library for PHP.

 *

 * @package ADOdb

 * @link https://adodb.org Project's web site and documentation

 * @link https://github.com/ADOdb/ADOdb Source code and issue tracker

 *

 * The ADOdb Library is dual-licensed, released under both the BSD 3-Clause

 * and the GNU Lesser General Public Licence (LGPL) v2.1 or, at your option,

 * any later version. This means you can use it in proprietary products.

 * See the LICENSE.md file distributed with this source code for details.

 * @license BSD-3-Clause

 * @license LGPL-2.1-or-later

 *

 * @copyright 2000-2013 John Lim

 * @copyright 2014 Damien Regad, Mark Newnham and the ADOdb community

 */

// security - hide paths

if (!defined('ADODB_DIR')) die();

if (!function_exists('sqlsrv_configure')) {

	die("mssqlnative extension not installed");

}

if (!function_exists('sqlsrv_set_error_handling')) {

	function sqlsrv_set_error_handling($constant) {

		sqlsrv_configure("WarningsReturnAsErrors", $constant);

	}

}

if (!function_exists('sqlsrv_log_set_severity')) {

	function sqlsrv_log_set_severity($constant) {

		sqlsrv_configure("LogSeverity", $constant);

	}

}

if (!function_exists('sqlsrv_log_set_subsystems')) {

	function sqlsrv_log_set_subsystems($constant) {

		sqlsrv_configure("LogSubsystems", $constant);

	}

}

class ADODB_mssqlnative extends ADOConnection {

	var $databaseType = "mssqlnative";

	var $dataProvider = "mssqlnative";

	var $replaceQuote = "''"; // string to use to replace quotes

	var $fmtDate = "'Y-m-d'";

	var $fmtTimeStamp = "'Y-m-d\TH:i:s'";

	/**

	 * Enabling InsertID capability will cause execution of an extra query

	 * {@see $identitySQL} after each INSERT statement. To improve performance

	 * when inserting a large number of records, you should switch this off by

	 * calling {@see enableLastInsertID enableLastInsertID(false)}.

	 * @var bool $hasInsertID

	 */

	var $hasInsertID = true;

	var $substr = "substring";

	var $length = 'len';

	var $hasAffectedRows = true;

	var $poorAffectedRows = false;

	var $metaDatabasesSQL = "select name from sys.sysdatabases where name <> 'master'";

	var $metaTablesSQL="select name,case when type='U' then 'T' else 'V' end from sysobjects where (type='U' or type='V') and (name not in ('sysallocations','syscolumns','syscomments','sysdepends','sysfilegroups','sysfiles','sysfiles1','sysforeignkeys','sysfulltextcatalogs','sysindexes','sysindexkeys','sysmembers','sysobjects','syspermissions','sysprotects','sysreferences','systypes','sysusers','sysalternates','sysconstraints','syssegments','REFERENTIAL_CONSTRAINTS','CHECK_CONSTRAINTS','CONSTRAINT_TABLE_USAGE','CONSTRAINT_COLUMN_USAGE','VIEWS','VIEW_TABLE_USAGE','VIEW_COLUMN_USAGE','SCHEMATA','TABLES','TABLE_CONSTRAINTS','TABLE_PRIVILEGES','COLUMNS','COLUMN_DOMAIN_USAGE','COLUMN_PRIVILEGES','DOMAINS','DOMAIN_CONSTRAINTS','KEY_COLUMN_USAGE','dtproperties'))";

	var $metaColumnsSQL =

		"select c.name,

		t.name as type,

		c.length,

		c.xprec as precision,

		c.xscale as scale,

		c.isnullable as nullable,

		c.cdefault as default_value,

		c.xtype,

		t.length as type_length,

		sc.is_identity

		from syscolumns c

		join systypes t on t.xusertype=c.xusertype

		join sysobjects o on o.id=c.id

		join sys.tables st on st.name=o.name

		join sys.columns sc on sc.object_id = st.object_id and sc.name=c.name

		where o.name='%s'";

	var $hasTop = 'top';		// support mssql SELECT TOP 10 * FROM TABLE

	var $hasGenID = true;

	var $sysDate = 'convert(datetime,convert(char,GetDate(),102),102)';

	var $sysTimeStamp = 'GetDate()';

	var $maxParameterLen = 4000;

	var $arrayClass = 'ADORecordSet_array_mssqlnative';

	var $uniqueSort = true;

	var $leftOuter = '*=';

	var $rightOuter = '=*';

	var $ansiOuter = true; // for mssql7 or later

	var $identitySQL = 'select SCOPE_IDENTITY()'; // 'select SCOPE_IDENTITY'; # for mssql 2000

	var $uniqueOrderBy = true;

	var $_bindInputArray = true;

	var $_dropSeqSQL = "drop table %s";

	var $connectionInfo    = array('ReturnDatesAsStrings'=>true);

	var $cachedSchemaFlush = false;

	var $sequences = false;

	var $mssql_version = '';

	function __construct()

	{

		if ($this->debug) {

			ADOConnection::outp("<pre>");

			sqlsrv_set_error_handling( SQLSRV_ERRORS_LOG_ALL );

			sqlsrv_log_set_severity( SQLSRV_LOG_SEVERITY_ALL );

			sqlsrv_log_set_subsystems(SQLSRV_LOG_SYSTEM_ALL);

			sqlsrv_configure('WarningsReturnAsErrors', 0);

		} else {

			sqlsrv_set_error_handling(0);

			sqlsrv_log_set_severity(0);

			sqlsrv_log_set_subsystems(SQLSRV_LOG_SYSTEM_ALL);

			sqlsrv_configure('WarningsReturnAsErrors', 0);

		}

	}

	/**

	 * Initializes the SQL Server version.

	 * Dies if connected to a non-supported version (2000 and older)

	 */

	function ServerVersion() {

		$data = $this->ServerInfo();

		preg_match('/^\d{2}/', $data['version'], $matches);

		$version = (int)reset($matches);

		// We only support SQL Server 2005 and up

		if($version < 9) {

			die("SQL SERVER VERSION {$data['version']} NOT SUPPORTED IN mssqlnative DRIVER");

		}

		$this->mssql_version = $version;

	}

	function ServerInfo() {

		global $ADODB_FETCH_MODE;

		static $arr = false;

		if (is_array($arr))

			return $arr;

		if ($this->fetchMode === false) {

			$savem = $ADODB_FETCH_MODE;

			$ADODB_FETCH_MODE = ADODB_FETCH_NUM;

		} elseif ($this->fetchMode >=0 && $this->fetchMode <=2) {

			$savem = $this->fetchMode;

		} else

			$savem = $this->SetFetchMode(ADODB_FETCH_NUM);

		$arrServerInfo = sqlsrv_server_info($this->_connectionID);

		$ADODB_FETCH_MODE = $savem;

		$arr = array();

		$arr['description'] = $arrServerInfo['SQLServerName'].' connected to '.$arrServerInfo['CurrentDatabase'];

		$arr['version'] = $arrServerInfo['SQLServerVersion'];//ADOConnection::_findvers($arr['description']);

		return $arr;

	}

	function IfNull( $field, $ifNull )

	{

		return " ISNULL($field, $ifNull) "; // if MS SQL Server

	}

	public function enableLastInsertID($enable = true) {

		$this->hasInsertID = $enable;

		$this->lastInsID = false;

	}

	/**

	 * Get the last value inserted into an IDENTITY column.

	 *

	 * The value will actually be set in {@see _query()} when executing an

	 * INSERT statement, but only if the connection's $hasInsertId property

	 * is true; this can be set with {@see enableLastInsertId()}.

	 *

	 * @inheritDoc

	 */

	protected function _insertID($table = '', $column = '')

	{

		return $this->lastInsID;

	}

	function _affectedrows()

	{

		if ($this->_queryID && is_resource($this->_queryID)) {

			return sqlsrv_rows_affected($this->_queryID);

		}

		return false;

	}

	function GenID($seq='adodbseq',$start=1) {

		switch($this->mssql_version){

		case 9:

		case 10:

			return $this->GenID2008($seq, $start);

			break;

		default:

			return $this->GenID2012($seq, $start);

			break;

		}

	}

	function CreateSequence($seq='adodbseq',$start=1)

	{

		switch($this->mssql_version){

		case 9:

		case 10:

			return $this->CreateSequence2008($seq, $start);

			break;

		default:

			return $this->CreateSequence2012($seq, $start);

			break;

		}

	}

	/**

	 * For Server 2005,2008, duplicate a sequence with an identity table

	 */

	function CreateSequence2008($seq='adodbseq',$start=1)

	{

		if($this->debug) ADOConnection::outp("<hr>CreateSequence($seq,$start)");

		sqlsrv_begin_transaction($this->_connectionID);

		$start -= 1;

		$this->Execute("create table $seq (id int)");//was float(53)

		$ok = $this->Execute("insert into $seq with (tablock,holdlock) values($start)");

		if (!$ok) {

			if($this->debug) ADOConnection::outp("<hr>Error: ROLLBACK");

			sqlsrv_rollback($this->_connectionID);

			return false;

		}

		sqlsrv_commit($this->_connectionID);

		return true;

	}

	/**

	 * Proper Sequences Only available to Server 2012 and up

	 */

	function CreateSequence2012($seq='adodbseq',$start=1){

		if (!$this->sequences){

			$sql = "SELECT name FROM sys.sequences";

			$this->sequences = $this->GetCol($sql);

		}

		$ok = $this->Execute("CREATE SEQUENCE $seq START WITH $start INCREMENT BY 1");

		if (!$ok)

			die("CANNOT CREATE SEQUENCE" . print_r(sqlsrv_errors(),true));

		$this->sequences[] = $seq;

	}

	/**

	 * For Server 2005,2008, duplicate a sequence with an identity table

	 */

	function GenID2008($seq='adodbseq',$start=1)

	{

		if($this->debug) ADOConnection::outp("<hr>CreateSequence($seq,$start)");

		sqlsrv_begin_transaction($this->_connectionID);

		$ok = $this->Execute("update $seq with (tablock,holdlock) set id = id + 1");

		if (!$ok) {

			$start -= 1;

			$this->Execute("create table $seq (id int)");//was float(53)

			$ok = $this->Execute("insert into $seq with (tablock,holdlock) values($start)");

			if (!$ok) {

				if($this->debug) ADOConnection::outp("<hr>Error: ROLLBACK");

				sqlsrv_rollback($this->_connectionID);

				return false;

			}

		}

		$num = $this->GetOne("select id from $seq");

		sqlsrv_commit($this->_connectionID);

		return $num;

	}

	/**

	 * Only available to Server 2012 and up

	 * Cannot do this the normal adodb way by trapping an error if the

	 * sequence does not exist because sql server will auto create a

	 * sequence with the starting number of -9223372036854775808

	 */

	function GenID2012($seq='adodbseq',$start=1)

	{

		/*

		 * First time in create an array of sequence names that we

		 * can use in later requests to see if the sequence exists

		 * the overhead is creating a list of sequences every time

		 * we need access to at least 1. If we really care about

		 * performance, we could maybe flag a 'nocheck' class variable

		 */

		if (!$this->sequences){

			$sql = "SELECT name FROM sys.sequences";

			$this->sequences = $this->GetCol($sql);

		}

		if (!is_array($this->sequences)

		|| is_array($this->sequences) && !in_array($seq,$this->sequences)){

			$this->CreateSequence2012($seq, $start);

		}

		$num = $this->GetOne("SELECT NEXT VALUE FOR $seq");

		return $num;

	}

	// Format date column in sql string given an input format that understands Y M D

	function SQLDate($fmt, $col=false)

	{

		if (!$col) {

			$col = $this->sysTimeStamp;

		}

		$s = '';

		$ConvertableFmt=array(

			"m/d/Y"=>101,  "m/d/y"=>101 // US

			,"Y.m.d"=>102, "y.m.d"=>102 // ANSI

			,"d/m/Y"=>103, "d/m/y"=>103 // French /english

			,"d.m.Y"=>104, "d.m.y"=>104 // German

			,"d-m-Y"=>105, "d-m-y"=>105 // Italian

			,"m-d-Y"=>110, "m-d-y"=>110 // US Dash

			,"Y/m/d"=>111, "y/m/d"=>111 // Japan

			,"Ymd"=>112,   "ymd"=>112   // ISO

			,"H:i:s"=>108 // Time

		);

		if (key_exists($fmt,$ConvertableFmt)) {

			return "convert (varchar ,$col," . $ConvertableFmt[$fmt] . ")";

		}

		$len = strlen($fmt);

		for ($i=0; $i < $len; $i++) {

			if ($s) $s .= '+';

			$ch = $fmt[$i];

			switch($ch) {

			case 'Y':

			case 'y':

				$s .= "datename(yyyy,$col)";

				break;

			case 'M':

				$s .= "convert(char(3),$col,0)";

				break;

			case 'm':

				$s .= "replace(str(month($col),2),' ','0')";

				break;

			case 'Q':

			case 'q':

				$s .= "datename(quarter,$col)";

				break;

			case 'D':

			case 'd':

				$s .= "replace(str(day($col),2),' ','0')";

				break;

			case 'h':

				$s .= "substring(convert(char(14),$col,0),13,2)";

				break;

			case 'H':

				$s .= "replace(str(datepart(hh,$col),2),' ','0')";

				break;

			case 'i':

				$s .= "replace(str(datepart(mi,$col),2),' ','0')";

				break;

			case 's':

				$s .= "replace(str(datepart(ss,$col),2),' ','0')";

				break;

			case 'a':

			case 'A':

				$s .= "substring(convert(char(19),$col,0),18,2)";

				break;

			case 'l':

				$s .= "datename(dw,$col)";

				break;

			default:

				if ($ch == '\\') {

					$i++;

					$ch = substr($fmt,$i,1);

				}

				$s .= $this->qstr($ch);

				break;

			}

		}

		return $s;

	}

	function BeginTrans()

	{

		if ($this->transOff) return true;

		$this->transCnt += 1;

		if ($this->debug) ADOConnection::outp('<hr>begin transaction');

		sqlsrv_begin_transaction($this->_connectionID);

		return true;

	}

	function CommitTrans($ok=true)

	{

		if ($this->transOff) return true;

		if ($this->debug) ADOConnection::outp('<hr>commit transaction');

		if (!$ok) return $this->RollbackTrans();

		if ($this->transCnt) $this->transCnt -= 1;

		sqlsrv_commit($this->_connectionID);

		return true;

	}

	function RollbackTrans()

	{

		if ($this->transOff) return true;

		if ($this->debug) ADOConnection::outp('<hr>rollback transaction');

		if ($this->transCnt) $this->transCnt -= 1;

		sqlsrv_rollback($this->_connectionID);

		return true;

	}

	function SetTransactionMode( $transaction_mode )

	{

		$this->_transmode  = $transaction_mode;

		if (empty($transaction_mode)) {

			$this->Execute('SET TRANSACTION ISOLATION LEVEL READ COMMITTED');

			return;

		}

		if (!stristr($transaction_mode,'isolation')) $transaction_mode = 'ISOLATION LEVEL '.$transaction_mode;

		$this->Execute("SET TRANSACTION ".$transaction_mode);

	}

	/*

		Usage:

		$this->BeginTrans();

		$this->RowLock('table1,table2','table1.id=33 and table2.id=table1.id'); # lock row 33 for both tables

		# some operation on both tables table1 and table2

		$this->CommitTrans();

		See http://www.swynk.com/friends/achigrik/SQL70Locks.asp

	*/

	function RowLock($tables,$where,$col='1 as adodbignore')

	{

		if ($col == '1 as adodbignore') $col = 'top 1 null as ignore';

		if (!$this->transCnt) $this->BeginTrans();

		return $this->GetOne("select $col from $tables with (ROWLOCK,HOLDLOCK) where $where");

	}

	function SelectDB($dbName)

	{

		$this->database = $dbName;

		if ($this->_connectionID) {

			$rs = $this->Execute('USE '.$dbName);

			if($rs) {

				return true;

			} else return false;

		}

		else return false;

	}

	function ErrorMsg()

	{

		$retErrors = sqlsrv_errors(SQLSRV_ERR_ALL);

		if($retErrors != null) {

			foreach($retErrors as $arrError) {

				$this->_errorMsg .= "SQLState: ".$arrError[ 'SQLSTATE']."\n";

				$this->_errorMsg .= "Error Code: ".$arrError[ 'code']."\n";

				$this->_errorMsg .= "Message: ".$arrError[ 'message']."\n";

			}

		}

		return $this->_errorMsg;

	}

	function ErrorNo()

	{

		$err = sqlsrv_errors(SQLSRV_ERR_ALL);

		if ($err && $err[0])

			return $err[0]['code'];

		else

			return 0;

	}

	// returns true or false

	function _connect($argHostname, $argUsername, $argPassword, $argDatabasename)

	{

		if (!function_exists('sqlsrv_connect'))

		{

			if ($this->debug)

				ADOConnection::outp('Microsoft SQL Server native driver (mssqlnative) not installed');

			return null;

		}

		if (!empty($this->port))

			/*

			* Port uses a comma

			*/

			$argHostname .= ",".$this->port;

		$connectionInfo 			= $this->connectionInfo;

		$connectionInfo["Database"]	= $argDatabasename;

		if ((string)$argUsername != '' || (string)$argPassword != '')

		{

			/*

			* If they pass either a userid or password, we assume

			* SQL Server authentication

			*/

			$connectionInfo["UID"]		= $argUsername;

			$connectionInfo["PWD"]		= $argPassword;

			if ($this->debug)

				ADOConnection::outp('userid or password supplied, attempting connection with SQL Server Authentication');

		}

		else

		{

			/*

			* If they don't pass either value, we won't add them to the

			* connection parameters. This will then force an attempt

			* to use windows authentication

			*/

			if ($this->debug)

				ADOConnection::outp('No userid or password supplied, attempting connection with Windows Authentication');

		}

		/*

		* Now merge in the passed connection parameters setting

		*/

		foreach ($this->connectionParameters as $options)

		{

			foreach($options as $parameter=>$value)

				$connectionInfo[$parameter] = $value;

		}

		if ($this->debug) ADOConnection::outp("connecting to host: $argHostname params: ".var_export($connectionInfo,true));

		if(!($this->_connectionID = @sqlsrv_connect($argHostname,$connectionInfo)))

		{

			if ($this->debug)

				ADOConnection::outp( 'Connection Failed: '.print_r( sqlsrv_errors(), true));

			return false;

		}

		$this->ServerVersion();

		return true;

	}

	// returns true or false

	function _pconnect($argHostname, $argUsername, $argPassword, $argDatabasename)

	{

		//return null;//not implemented. NOTE: Persistent connections have no effect if PHP is used as a CGI program. (FastCGI!)

		return $this->_connect($argHostname, $argUsername, $argPassword, $argDatabasename);

	}

	function Prepare($sql)

	{

		return $sql; // prepare does not work properly with bind parameters as bind parameters are managed by sqlsrv_prepare!

	}

	// returns concatenated string

	// MSSQL requires integers to be cast as strings

	// automatically cast every datatype to VARCHAR(255)

	// @author David Rogers (introspectshun)

	function Concat()

	{

		$s = "";

		$arr = func_get_args();

		// Split single record on commas, if possible

		if (sizeof($arr) == 1) {

			foreach ($arr as $arg) {

				$args = explode(',', $arg);

			}

			$arr = $args;

		}

		array_walk(

			$arr,

			function(&$value, $key) {

				$value = "CAST(" . $value . " AS VARCHAR(255))";

			}

		);

		$s = implode('+',$arr);

		if (sizeof($arr) > 0) return "$s";

		return '';

	}

	/*

		Unfortunately, it appears that mssql cannot handle varbinary > 255 chars

		So all your blobs must be of type "image".

		Remember to set in php.ini the following...

		; Valid range 0 - 2147483647. Default = 4096.

		mssql.textlimit = 0 ; zero to pass through

		; Valid range 0 - 2147483647. Default = 4096.

		mssql.textsize = 0 ; zero to pass through

	*/

	function UpdateBlob($table,$column,$val,$where,$blobtype='BLOB')

	{

		if (strtoupper($blobtype) == 'CLOB') {

			$sql = "UPDATE $table SET $column='" . $val . "' WHERE $where";

			return $this->Execute($sql) != false;

		}

		$sql = "UPDATE $table SET $column=0x".bin2hex($val)." WHERE $where";

		return $this->Execute($sql) != false;

	}

	/**

	 * Execute a query.

	 *

	 * If executing an INSERT statement and $hasInsertId is true, will set

	 * $lastInsId.

	 *

	 * @param string $sql

	 * @param array $inputarr

	 * @return resource|false Query Id if successful, otherwise false

	 */

	function _query($sql, $inputarr = false)

	{

		$this->_errorMsg = false;

		if (is_array($sql)) {

			$sql = $sql[1];

		}

		// Handle native driver flaw for retrieving the last insert ID

		if ($this->hasInsertID) {

			// Check if it's an INSERT statement

			$retrieveLastInsertID = preg_match(

				'/^\W*insert[\s\w()[\]",.]+values\s*\((?:[^;\']|\'\'|(?:(?:\'\')*\'[^\']+\'(?:\'\')*))*;?$/i',

				$sql

			);

			if ($retrieveLastInsertID) {

				// Append the identity SQL, so it is executed in the same

				// scope as the insert query.

				$sql .= '; ' . $this->identitySQL;

			}

		} else {

			$retrieveLastInsertID = false;

		}

		if ($inputarr) {

			// Ensure that the input array is indexed numerically, as required

			// by sqlsrv_query(). If param() was used to create portable binds

			// then the array might be associative.

			$inputarr = array_values($inputarr);

			$rez = sqlsrv_query($this->_connectionID, $sql, $inputarr);

		} else {

			$rez = sqlsrv_query($this->_connectionID, $sql);

		}

		$this->lastInsID = false;

		if (!$rez) {

			$rez = false;

		} elseif ($retrieveLastInsertID) {

			// Get the inserted id from the last result

			// Note: loop is required as server may return more than one row,

			// e.g. if triggers are involved (see #41)

			while (sqlsrv_next_result($rez)) {

				sqlsrv_fetch($rez);

				$this->lastInsID = sqlsrv_get_field($rez, 0);

			}

		}

		return $rez;

	}

	/**

	 * Rolls back pending transactions and closes the connection.

	 *

	 * @return bool True, unless the connection id is invalid

	 */

	function _close()

	{

		if ($this->transCnt) {

			$this->RollbackTrans();

		}

		if ($this->_connectionID) {

			return sqlsrv_close($this->_connectionID);

		}

		$this->_connectionID = false;

		return true;

	}

	function MetaIndexes($table,$primary=false, $owner = false)

	{

		$table = $this->qstr($table);

		$sql = "SELECT i.name AS ind_name, C.name AS col_name, USER_NAME(O.uid) AS Owner, c.colid, k.Keyno,

			CASE WHEN I.indid BETWEEN 1 AND 254 AND (I.status & 2048 = 2048 OR I.Status = 16402 AND O.XType = 'V') THEN 1 ELSE 0 END AS IsPK,

			CASE WHEN I.status & 2 = 2 THEN 1 ELSE 0 END AS IsUnique

			FROM dbo.sysobjects o INNER JOIN dbo.sysindexes I ON o.id = i.id

			INNER JOIN dbo.sysindexkeys K ON I.id = K.id AND I.Indid = K.Indid

			INNER JOIN dbo.syscolumns c ON K.id = C.id AND K.colid = C.Colid

			WHERE LEFT(i.name, 8) <> '_WA_Sys_' AND o.status >= 0 AND O.Name LIKE $table

			ORDER BY O.name, I.Name, K.keyno";

		global $ADODB_FETCH_MODE;

		$save = $ADODB_FETCH_MODE;

		$ADODB_FETCH_MODE = ADODB_FETCH_NUM;

		if ($this->fetchMode !== FALSE) {

			$savem = $this->SetFetchMode(FALSE);

		}

		$rs = $this->Execute($sql);

		if (isset($savem)) {

			$this->SetFetchMode($savem);

		}

		$ADODB_FETCH_MODE = $save;

		if (!is_object($rs)) {

			return FALSE;

		}

		$indexes = array();

		while ($row = $rs->FetchRow()) {

			if (!$primary && $row[5]) continue;

			$indexes[$row[0]]['unique'] = $row[6];

			$indexes[$row[0]]['columns'][] = $row[1];

		}

		return $indexes;

	}

	public function metaForeignKeys($table, $owner = '', $upper = false, $associative = false)

	{

		global $ADODB_FETCH_MODE;

		$save = $ADODB_FETCH_MODE;

		$ADODB_FETCH_MODE = ADODB_FETCH_NUM;

		$table = $this->qstr(strtoupper($table));

		$sql =

			"select object_name(constid) as constraint_name,

				col_name(fkeyid, fkey) as column_name,

				object_name(rkeyid) as referenced_table_name,

				col_name(rkeyid, rkey) as referenced_column_name

			from sysforeignkeys

			where upper(object_name(fkeyid)) = $table

			order by constraint_name, referenced_table_name, keyno";

		$constraints = $this->GetArray($sql);

		$ADODB_FETCH_MODE = $save;

		$arr = false;

		foreach($constraints as $constr) {

			//print_r($constr);

			$arr[$constr[0]][$constr[2]][] = $constr[1].'='.$constr[3];

		}

		if (!$arr) return false;

		$arr2 = false;

		foreach($arr as $k => $v) {

			foreach($v as $a => $b) {

				if ($upper) $a = strtoupper($a);

				if (is_array($arr2[$a])) {	// a previous foreign key was define for this reference table, we merge the new one

					$arr2[$a] = array_merge($arr2[$a], $b);

				} else {

					$arr2[$a] = $b;

				}

			}

		}

		return $arr2;

	}

	//From: Fernando Moreira <FMoreira@imediata.pt>

	function MetaDatabases()

	{

		$this->SelectDB("master");

		$rs = $this->Execute($this->metaDatabasesSQL);

		$rows = $rs->GetRows();

		$ret = array();

		for($i=0;$i<count($rows);$i++) {

			$ret[] = $rows[$i][0];

		}

		$this->SelectDB($this->database);

		if($ret)

			return $ret;

		else

			return false;

	}

	// "Stein-Aksel Basma" <basma@accelero.no>

	// tested with MSSQL 2000

	function MetaPrimaryKeys($table, $owner=false)

	{

		global $ADODB_FETCH_MODE;

		$schema = '';

		$this->_findschema($table,$schema);

		if (!$schema) $schema = $this->database;

		if ($schema) $schema = "and k.table_catalog like '$schema%'";

		$sql = "select distinct k.column_name,ordinal_position from information_schema.key_column_usage k,

		information_schema.table_constraints tc

		where tc.constraint_name = k.constraint_name and tc.constraint_type =

		'PRIMARY KEY' and k.table_name = '$table' $schema order by ordinal_position ";

		$savem = $ADODB_FETCH_MODE;

		$ADODB_FETCH_MODE = ADODB_FETCH_NUM;

		$a = $this->GetCol($sql);

		$ADODB_FETCH_MODE = $savem;

		if ($a && sizeof($a)>0) return $a;

		$false = false;

		return $false;

	}

	function MetaTables($ttype=false,$showSchema=false,$mask=false)

	{

		if ($mask) {

			$save = $this->metaTablesSQL;

			$mask = $this->qstr(($mask));

			$this->metaTablesSQL .= " AND name like $mask";

		}

		$ret = ADOConnection::MetaTables($ttype,$showSchema);

		if ($mask) {

			$this->metaTablesSQL = $save;

		}

		return $ret;

	}

	function MetaColumns($table, $upper=true, $schema=false){

		/*

		* A simple caching mechanism, to be replaced in ADOdb V6

		*/

		static $cached_columns = array();

		if ($this->cachedSchemaFlush)

			$cached_columns = array();

		if (array_key_exists($table,$cached_columns)){

			return $cached_columns[$table];

		}

		$this->_findschema($table,$schema);

		if ($schema) {

			$dbName = $this->database;

			$this->SelectDB($schema);

		}

		global $ADODB_FETCH_MODE;

		$save = $ADODB_FETCH_MODE;

		$ADODB_FETCH_MODE = ADODB_FETCH_NUM;

		if ($this->fetchMode !== false) $savem = $this->SetFetchMode(false);

		$rs = $this->Execute(sprintf($this->metaColumnsSQL,$table));

		if ($schema) {

			$this->SelectDB($dbName);

		}

		if (isset($savem)) $this->SetFetchMode($savem);

		$ADODB_FETCH_MODE = $save;

		if (!is_object($rs)) {

			$false = false;

			return $false;

		}

		$retarr = array();

		while (!$rs->EOF){

			$fld = new ADOFieldObject();

			if (array_key_exists(0,$rs->fields)) {

				$fld->name          = $rs->fields[0];

				$fld->type          = $rs->fields[1];

				$fld->max_length    = $rs->fields[2];

				$fld->precision     = $rs->fields[3];

				$fld->scale         = $rs->fields[4];

				$fld->not_null      =!$rs->fields[5];

				$fld->has_default   = $rs->fields[6];

				$fld->xtype         = $rs->fields[7];

				$fld->type_length   = $rs->fields[8];

				$fld->auto_increment= $rs->fields[9];

			} else {

				$fld->name          = $rs->fields['name'];

				$fld->type          = $rs->fields['type'];

				$fld->max_length    = $rs->fields['length'];

				$fld->precision     = $rs->fields['precision'];

				$fld->scale         = $rs->fields['scale'];

				$fld->not_null      =!$rs->fields['nullable'];

				$fld->has_default   = $rs->fields['default_value'];

				$fld->xtype         = $rs->fields['xtype'];

				$fld->type_length   = $rs->fields['type_length'];

				$fld->auto_increment= $rs->fields['is_identity'];

			}

			if ($save == ADODB_FETCH_NUM)

				$retarr[] = $fld;

			else

				$retarr[strtoupper($fld->name)] = $fld;

			$rs->MoveNext();

		}

		$rs->Close();

		$cached_columns[$table] = $retarr;

		return $retarr;

	}

	/**

	* Returns a substring of a varchar type field

	*

	* The SQL server version varies because the length is mandatory, so

	* we append a reasonable string length

	*

	* @param	string	$fld	The field to sub-string

	* @param	int		$start	The start point

	* @param	int		$length	An optional length

	*

	* @return	The SQL text

	*/

	function substr($fld,$start,$length=0)

	{

		if ($length == 0)

			/*

		     * The length available to varchar is 2GB, but that makes no

			 * sense in a substring, so I'm going to arbitrarily limit

			 * the length to 1K, but you could change it if you want

			 */

			$length = 1024;

		$text = "SUBSTRING($fld,$start,$length)";

		return $text;

	}

	/**

	* Returns the maximum size of a MetaType C field. Because of the

	* database design, SQL Server places no limits on the size of data inserted

	* Although the actual limit is 2^31-1 bytes.

	*

	* @return int

	*/

	function charMax()

	{

		return ADODB_STRINGMAX_NOLIMIT;

	}

	/**

	* Returns the maximum size of a MetaType X field. Because of the

	* database design, SQL Server places no limits on the size of data inserted

	* Although the actual limit is 2^31-1 bytes.

	*

	* @return int

	*/

	function textMax()

	{

		return ADODB_STRINGMAX_NOLIMIT;

	}

	/**

	 * Lists procedures, functions and methods in an array.

	 *

	 * @param	string $procedureNamePattern (optional)

	 * @param	string $catalog				 (optional)

	 * @param	string $schemaPattern		 (optional)

	 * @return array of stored objects in current database.

	 *

	 */

	public function metaProcedures($procedureNamePattern = null, $catalog  = null, $schemaPattern  = null)

	{

		$metaProcedures = array();

		$procedureSQL   = '';

		$catalogSQL     = '';

		$schemaSQL      = '';

		if ($procedureNamePattern)

			$procedureSQL = "AND ROUTINE_NAME LIKE " . strtoupper($this->qstr($procedureNamePattern));

		if ($catalog)

			$catalogSQL = "AND SPECIFIC_SCHEMA=" . strtoupper($this->qstr($catalog));

		if ($schemaPattern)

			$schemaSQL = "AND ROUTINE_SCHEMA LIKE {$this->qstr($schemaPattern)}";

		$fields = "	ROUTINE_NAME,ROUTINE_TYPE,ROUTINE_SCHEMA,ROUTINE_CATALOG";

		$SQL = "SELECT $fields

			FROM {$this->database}.information_schema.routines

			WHERE 1=1

				$procedureSQL

				$catalogSQL

				$schemaSQL

			ORDER BY ROUTINE_NAME

			";

		$result = $this->execute($SQL);

		if (!$result)

			return false;

		while ($r = $result->fetchRow()){

			if (!isset($r[0]))

				/*

				* Convert to numeric

				*/

				$r = array_values($r);

			$procedureName = $r[0];

			$schemaName    = $r[2];

			$routineCatalog= $r[3];

			$metaProcedures[$procedureName] = array('type'=> $r[1],

												   'catalog' => $routineCatalog,