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sqlsrv.php
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sqlsrv.php
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<?php
/**
* @package Joomla.Platform
* @subpackage Database
*
* @copyright Copyright (C) 2005 - 2011 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE
*/
defined('JPATH_PLATFORM') or die();
jimport('joomla.database.database');
jimport('joomla.string.string');
JLoader::register('JDatabaseQuerySQLSrv', dirname(__FILE__) . '/sqlsrvquery.php');
/**
* SQL Server database driver
*
* @package Joomla.Platform
* @subpackage Database
* @see http://msdn.microsoft.com/en-us/library/cc296152(SQL.90).aspx
* @since 11.1
*/
class JDatabaseSQLSrv extends JDatabase
{
/**
* The name of the database driver.
*
* @var string
* @since 11.1
*/
public $name = 'sqlsrv';
/**
* The character(s) used to quote SQL statement names such as table names or field names,
* etc. The child classes should define this as necessary. If a single character string the
* same character is used for both sides of the quoted name, else the first character will be
* used for the opening quote and the second for the closing quote.
*
* @var string
* @since 11.1
*/
protected $nameQuote;
/**
* The null or zero representation of a timestamp for the database driver. This should be
* defined in child classes to hold the appropriate value for the engine.
*
* @var string
* @since 11.1
*/
protected $nullDate = '1900-01-01 00:00:00';
/**
* Test to see if the SQLSRV connector is available.
*
* @return boolean True on success, false otherwise.
*
* @since 11.1
*/
public static function test()
{
return (function_exists('sqlsrv_connect'));
}
/**
* Constructor.
*
* @param array $options List of options used to configure the connection
*
* @return void
*
* @since 11.1
*/
protected function __construct($options)
{
// Get some basic values from the options.
$options['host'] = (isset($options['host'])) ? $options['host'] : 'localhost';
$options['user'] = (isset($options['user'])) ? $options['user'] : '';
$options['password'] = (isset($options['password'])) ? $options['password'] : '';
$options['database'] = (isset($options['database'])) ? $options['database'] : '';
$options['select'] = (isset($options['select'])) ? (bool) $options['select'] : true;
// Build the connection configuration array.
$config = array(
'Database' => $options['database'],
'uid' => $options['user'],
'pwd' => $options['password'],
'CharacterSet' => 'UTF-8',
'ReturnDatesAsStrings' => true);
// Make sure the SQLSRV extension for PHP is installed and enabled.
if (!function_exists('sqlsrv_connect'))
{
// Legacy error handling switch based on the JError::$legacy switch.
// @deprecated 12.1
if (JError::$legacy)
{
$this->errorNum = 1;
$this->errorMsg = JText::_('JLIB_DATABASE_ERROR_ADAPTER_SQLSRV');
return;
}
else
{
throw new JDatabaseException(JText::_('JLIB_DATABASE_ERROR_ADAPTER_SQLSRV'));
}
}
// Attempt to connect to the server.
if (!($this->connection = @ sqlsrv_connect($options['host'], $config)))
{
// Legacy error handling switch based on the JError::$legacy switch.
// @deprecated 12.1
if (JError::$legacy)
{
$this->errorNum = 2;
$this->errorMsg = JText::_('JLIB_DATABASE_ERROR_CONNECT_SQLSRV');
return;
}
else
{
throw new JDatabaseException(JText::_('JLIB_DATABASE_ERROR_CONNECT_SQLSRV'));
}
}
// Make sure that DB warnings are not returned as errors.
sqlsrv_configure('WarningsReturnAsErrors', 0);
// Finalize initialisation
parent::__construct($options);
// If auto-select is enabled select the given database.
if ($options['select'] && !empty($options['database']))
{
$this->select($options['database']);
}
}
/**
* Destructor.
*
* @return void
*
* @since 11.1
*/
public function __destruct()
{
if (is_resource($this->connection))
{
sqlsrv_close($this->connection);
}
}
/**
* Get table constraints
*
* @param string $tableName The name of the database table.
*
* @return array Any constraints available for the table.
*
* @since 11.1
*/
protected function getTableConstraints($tableName)
{
$query = $this->getQuery(true);
$this->setQuery(
'SELECT CONSTRAINT_NAME FROM' . ' INFORMATION_SCHEMA.TABLE_CONSTRAINTS' . ' WHERE TABLE_NAME = ' . $query->quote($tableName)
);
return $this->loadColumn();
}
/**
* Rename constraints.
*
* @param array $constraints Array(strings) of table constraints
* @param string $prefix A string
* @param string $backup A string
*
* @return void
*
* @since 11.1
*/
protected function renameConstraints($constraints = array(), $prefix = null, $backup = null)
{
foreach ($constraints as $constraint)
{
$this->setQuery('sp_rename ' . $constraint . ',' . str_replace($prefix, $backup, $constraint));
$this->query();
}
}
/**
* Method to escape a string for usage in an SQL statement.
*
* The escaping for MSSQL isn't handled in the driver though that would be nice. Because of this we need
* to handle the escaping ourselves.
*
* @param string $text The string to be escaped.
* @param boolean $extra Optional parameter to provide extra escaping.
*
* @return string The escaped string.
*
* @since 11.1
*/
public function escape($text, $extra = false)
{
// TODO: MSSQL Compatible escaping
$result = addslashes($text);
$result = str_replace("\'", "''", $result);
$result = str_replace('\"', '"', $result);
//$result = str_replace("\\", "''", $result);
if ($extra)
{
// We need the below str_replace since the search in sql server doesnt recognize _ character.
$result = str_replace('_', '[_]', $result);
}
return $result;
}
/**
* Determines if the connection to the server is active.
*
* @return boolean True if connected to the database engine.
*
* @since 11.1
*/
public function connected()
{
// TODO: Run a blank query here
return true;
}
/**
* Drops a table from the database.
*
* @param string $tableName The name of the database table to drop.
* @param boolean $ifExists Optionally specify that the table must exist before it is dropped.
*
* @return JDatabaseSQLSrv Returns this object to support chaining.
*
* @since 11.1
*/
function dropTable($tableName, $ifExists = true)
{
$query = $this->getQuery(true);
$this->setQuery(
'IF EXISTS(SELECT TABLE_NAME FROM' . ' INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = ' . $query->quote($tableName) . ') DROP TABLE'
);
$this->query();
return $this;
}
/**
* Get the number of affected rows for the previous executed SQL statement.
*
* @return integer The number of affected rows.
*
* @since 11.1
*/
public function getAffectedRows()
{
return sqlsrv_rows_affected($this->cursor);
}
/**
* Method to get the database collation in use by sampling a text field of a table in the database.
*
* @return mixed The collation in use by the database or boolean false if not supported.
*
* @since 11.1
*/
public function getCollation()
{
// TODO: Not fake this
return 'MSSQL UTF-8 (UCS2)';
}
/**
* Gets an exporter class object.
*
* @return JDatabaseExporterSQLAzure An exporter object.
*
* @since 11.1
* @throws JDatabaseException
*/
public function getExporter()
{
// Make sure we have an exporter class for this driver.
if (!class_exists('JDatabaseExporterSQLAzure'))
{
throw new JDatabaseException(JText::_('JLIB_DATABASE_ERROR_MISSING_EXPORTER'));
}
$o = new JDatabaseExporterSQLAzure();
$o->setDbo($this);
return $o;
}
/**
* Gets an importer class object.
*
* @return JDatabaseImporterSQLAzure An importer object.
*
* @since 11.1
* @throws JDatabaseException
*/
public function getImporter()
{
// Make sure we have an importer class for this driver.
if (!class_exists('JDatabaseImporterSQLAzure'))
{
throw new JDatabaseException(JText::_('JLIB_DATABASE_ERROR_MISSING_IMPORTER'));
}
$o = new JDatabaseImporterSQLAzure();
$o->setDbo($this);
return $o;
}
/**
* Get the number of returned rows for the previous executed SQL statement.
*
* @param resource $cursor An optional database cursor resource to extract the row count from.
*
* @return integer The number of returned rows.
*
* @since 11.1
*/
public function getNumRows($cursor = null)
{
return sqlsrv_num_rows($cursor ? $cursor : $this->cursor);
}
/**
* Get the current or query, or new JDatabaseQuery object.
*
* @param boolean $new False to return the last query set, True to return a new JDatabaseQuery object.
*
* @return mixed The current value of the internal SQL variable or a new JDatabaseQuery object.
*
* @since 11.1
* @throws JDatabaseException
*/
public function getQuery($new = false)
{
if ($new)
{
// Make sure we have a query class for this driver.
if (!class_exists('JDatabaseQuerySQLAzure'))
{
throw new JDatabaseException(JText::_('JLIB_DATABASE_ERROR_MISSING_QUERY'));
}
return new JDatabaseQuerySQLAzure($this);
}
else
{
return $this->sql;
}
}
/**
* Retrieves field information about the given tables.
*
* @param mixed $tables A table name or a list of table names.
* @param boolean $typeOnly True to only return field types.
*
* @return array An array of fields by table.
*
* @since 11.1
* @throws JDatabaseException
*/
public function getTableColumns($tables, $typeOnly = true)
{
// Initialise variables.
$result = array();
// Sanitize input to an array and iterate over the list.
settype($tables, 'array');
foreach ($tables as $table)
{
// Set the query to get the table fields statement.
$this->setQuery(
'SELECT column_name as Field, data_type as Type, is_nullable as \'Null\', column_default as \'Default\'' .
' FROM information_schema.columns' . ' WHERE table_name = ' . $this->quote($table)
);
$fields = $this->loadObjectList();
// If we only want the type as the value add just that to the list.
if ($typeOnly)
{
foreach ($fields as $field)
{
$result[$table][$field->Field] = preg_replace("/[(0-9)]/", '', $field->Type);
}
}
// If we want the whole field data object add that to the list.
else
{
foreach ($fields as $field)
{
$result[$table][$field->Field] = $field;
}
}
}
return $result;
}
/**
* Shows the table CREATE statement that creates the given tables.
*
* This is unsupported by MSSQL.
*
* @param mixed $tables A table name or a list of table names.
*
* @return array A list of the create SQL for the tables.
*
* @since 11.1
* @throws JDatabaseException
*/
public function getTableCreate($tables)
{
return '';
}
/**
* Get the details list of keys for a table.
*
* @param string $table The name of the table.
*
* @return array An arry of the column specification for the table.
*
* @since 11.1
* @throws JDatabaseException
*/
public function getTableKeys($table)
{
// TODO To implement.
return array();
}
/**
* Method to get an array of all tables in the database.
*
* @return array An array of all the tables in the database.
*
* @since 11.1
* @throws JDatabaseException
*/
public function getTableList()
{
// Set the query to get the tables statement.
$this->setQuery('SELECT name FROM sysobjects WHERE xtype = \'U\';');
$tables = $this->loadColumn();
return $tables;
}
/**
* Get the version of the database connector.
*
* @return string The database connector version.
*
* @since 11.1
*/
public function getVersion()
{
//TODO: Don't hardcode this.
return '5.1.0';
}
/**
* Determines if the database engine supports UTF-8 character encoding.
*
* @return boolean True if supported.
*
* @since 11.1
*/
public function hasUTF()
{
return true;
}
/**
* Method to get the auto-incremented value from the last INSERT statement.
*
* @return integer The value of the auto-increment field from the last inserted row.
*
* @since 11.1
*/
public function insertid()
{
// TODO: SELECT IDENTITY
$this->setQuery('SELECT @@IDENTITY');
return (int) $this->loadResult();
}
/**
* Execute the SQL statement.
*
* @return mixed A database cursor resource on success, boolean false on failure.
*
* @since 11.1
* @throws JDatabaseException
*/
public function query()
{
if (!is_resource($this->connection))
{
// Legacy error handling switch based on the JError::$legacy switch.
// @deprecated 12.1
if (JError::$legacy)
{
if ($this->debug)
{
JError::raiseError(500, 'JDatabaseDriverSQLAzure::query: ' . $this->errorNum . ' - ' . $this->errorMsg);
}
return false;
}
else
{
JLog::add(JText::sprintf('JLIB_DATABASE_QUERY_FAILED', $this->errorNum, $this->errorMsg), JLog::ERROR, 'database');
throw new JDatabaseException($this->errorMsg, $this->errorNum);
}
}
// Take a local copy so that we don't modify the original query and cause issues later
$sql = $this->replacePrefix((string) $this->sql);
if ($this->limit > 0 || $this->offset > 0)
{
$sql = $this->limit($sql, $this->limit, $this->offset);
}
// If debugging is enabled then let's log the query.
if ($this->debug)
{
// Increment the query counter and add the query to the object queue.
$this->count++;
$this->log[] = $sql;
JLog::add($sql, JLog::DEBUG, 'databasequery');
}
// Reset the error values.
$this->errorNum = 0;
$this->errorMsg = '';
// sqlsrv_num_rows requires a static or keyset cursor.
if (JString::startsWith(ltrim(strtoupper($sql)), 'SELECT'))
{
$array = array('Scrollable' => SQLSRV_CURSOR_KEYSET);
}
else
{
$array = array();
}
// Execute the query.
$this->cursor = sqlsrv_query($this->connection, $sql, array(), $array);
// If an error occurred handle it.
if (!$this->cursor)
{
// Populate the errors.
$errors = sqlsrv_errors();
$this->errorNum = $errors[0]['SQLSTATE'];
$this->errorMsg = $errors[0]['message'] . 'SQL=' . $sql;
// Legacy error handling switch based on the JError::$legacy switch.
// @deprecated 12.1
if (JError::$legacy)
{
if ($this->debug)
{
JError::raiseError(500, 'JDatabaseDriverSQLAzure::query: ' . $this->errorNum . ' - ' . $this->errorMsg);
}
return false;
}
else
{
JLog::add(JText::sprintf('JLIB_DATABASE_QUERY_FAILED', $this->errorNum, $this->errorMsg), JLog::ERROR, 'databasequery');
throw new JDatabaseException($this->errorMsg, $this->errorNum);
}
}
return $this->cursor;
}
/**
* Select a database for use.
*
* @param string $database The name of the database to select for use.
*
* @return boolean True if the database was successfully selected.
*
* @since 11.1
* @throws JDatabaseException
*/
public function select($database)
{
if (!$database)
{
return false;
}
if (!sqlsrv_query($this->connection, 'USE ' . $database, null, array('scrollable' => SQLSRV_CURSOR_STATIC)))
{
// Legacy error handling switch based on the JError::$legacy switch.
// @deprecated 12.1
if (JError::$legacy)
{
$this->errorNum = 3;
$this->errorMsg = JText::_('JLIB_DATABASE_ERROR_DATABASE_CONNECT');
return false;
}
else
{
throw new JDatabaseException(JText::_('JLIB_DATABASE_ERROR_DATABASE_CONNECT'));
}
}
return true;
}
/**
* Set the connection to use UTF-8 character encoding.
*
* @return boolean True on success.
*
* @since 11.1
*/
public function setUTF()
{
// TODO: Remove this?
}
/**
* Method to commit a transaction.
*
* @return void
*
* @since 11.1
* @throws JDatabaseException
*/
public function transactionCommit()
{
$this->setQuery('COMMIT TRANSACTION');
$this->query();
}
/**
* Method to roll back a transaction.
*
* @return void
*
* @since 11.1
* @throws JDatabaseException
*/
public function transactionRollback()
{
$this->setQuery('ROLLBACK TRANSACTION');
$this->query();
}
/**
* Method to initialize a transaction.
*
* @return void
*
* @since 11.1
* @throws JDatabaseException
*/
public function transactionStart()
{
$this->setQuery('START TRANSACTION');
$this->query();
}
/**
* Method to fetch a row from the result set cursor as an array.
*
* @param mixed $cursor The optional result set cursor from which to fetch the row.
*
* @return mixed Either the next row from the result set or false if there are no more rows.
*
* @since 11.1
*/
protected function fetchArray($cursor = null)
{
return sqlsrv_fetch_array($cursor ? $cursor : $this->cursor, SQLSRV_FETCH_NUMERIC);
}
/**
* Method to fetch a row from the result set cursor as an associative array.
*
* @param mixed $cursor The optional result set cursor from which to fetch the row.
*
* @return mixed Either the next row from the result set or false if there are no more rows.
*
* @since 11.1
*/
protected function fetchAssoc($cursor = null)
{
return sqlsrv_fetch_array($cursor ? $cursor : $this->cursor, SQLSRV_FETCH_ASSOC);
}
/**
* Method to fetch a row from the result set cursor as an object.
*
* @param mixed $cursor The optional result set cursor from which to fetch the row.
* @param string $class The class name to use for the returned row object.
*
* @return mixed Either the next row from the result set or false if there are no more rows.
*
* @since 11.1
*/
protected function fetchObject($cursor = null, $class = 'stdClass')
{
return sqlsrv_fetch_object($cursor ? $cursor : $this->cursor, $class);
}
/**
* Method to free up the memory used for the result set.
*
* @param mixed $cursor The optional result set cursor from which to fetch the row.
*
* @return void
*
* @since 11.1
*/
protected function freeResult($cursor = null)
{
sqlsrv_free_stmt($cursor ? $cursor : $this->cursor);
}
/**
* Diagnostic method to return explain information for a query.
*
* @return string The explain output.
*
* @deprecated 12.1
* @see http://msdn.microsoft.com/en-us/library/aa259203%28SQL.80%29.aspx
* @since 11.1
*/
public function explain()
{
// Deprecation warning.
JLog::add('JDatabase::explain() is deprecated.', JLog::WARNING, 'deprecated');
// Backup the current query so we can reset it later.
$backup = $this->sql;
// SET SHOWPLAN_ALL ON - will make sqlsrv to show some explain of query instead of run it
$this->setQuery('SET SHOWPLAN_ALL ON');
$this->query();
// Execute the query and get the result set cursor.
$this->setQuery($backup);
if (!($cursor = $this->query()))
{
return null;
}
// Build the HTML table.
$first = true;
$buffer = '<table id="explain-sql">';
$buffer .= '<thead><tr><td colspan="99">' . $this->getQuery() . '</td></tr>';
while ($row = $this->fetchAssoc($cursor))
{
if ($first)
{
$buffer .= '<tr>';
foreach ($row as $k => $v)
{
$buffer .= '<th>' . $k . '</th>';
}
$buffer .= '</tr></thead>';
$first = false;
}
$buffer .= '<tbody><tr>';
foreach ($row as $k => $v)
{
$buffer .= '<td>' . $v . '</td>';
}
$buffer .= '</tr>';
}
$buffer .= '</tbody></table>';
// Free up system resources and return.
$this->freeResult($cursor);
// Remove the explain status.
$this->setQuery('SET SHOWPLAN_ALL OFF');
$this->query();
// Restore the original query to its state before we ran the explain.
$this->sql = $backup;
return $buffer;
}
/**
* Execute a query batch.
*
* @param boolean $abortOnError Abort on error.
* @param boolean $transactionSafe Transaction safe queries.
*
* @return mixed A database resource if successful, false if not.
*
* @since 11.1
* @deprecated 12.1
*/
public function queryBatch($abortOnError = true, $transactionSafe = false)
{
// Deprecation warning.
JLog::add('JDatabase::queryBatch() is deprecated.', JLog::WARNING, 'deprecated');
$sql = $this->replacePrefix((string) $this->sql);
$this->errorNum = 0;
$this->errorMsg = '';
// If the batch is meant to be transaction safe then we need to wrap it in a transaction.
if ($transactionSafe)
{
$this->_sql = 'BEGIN TRANSACTION;' . $this->sql . '; COMMIT TRANSACTION;';
}
$queries = $this->splitSql($sql);
$error = 0;
foreach ($queries as $query)
{
$query = trim($query);
if ($query != '')
{
$this->cursor = sqlsrv_query($this->connection, $query, null, array('scrollable' => SQLSRV_CURSOR_STATIC));
if ($this->_debug)
{
$this->count++;
$this->log[] = $query;
}
if (!$this->cursor)
{
$error = 1;
$errors = sqlsrv_errors();
$this->errorNum = $errors[0]['sqlstate'];
$this->errorMsg = $errors[0]['message'];
if ($abortOnError)
{
return $this->cursor;
}
}
}
}
return $error ? false : true;
}
/**
* Method to check and see if a field exists in a table.
*
* @param string $table The table in which to verify the field.
* @param string $field The field to verify.
*
* @return boolean True if the field exists in the table.
*
* @since 11.1
*/
protected function checkFieldExists($table, $field)
{
$table = $this->replacePrefix((string) $table);
$sql = "SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS" . " WHERE TABLE_NAME = '$table' AND COLUMN_NAME = '$field'" .
" ORDER BY ORDINAL_POSITION";
$this->setQuery($sql);
if ($this->loadResult())
{
return true;
}
else
{
return false;
}
}
/**
* Method to wrap an SQL statement to provide a LIMIT and OFFSET behavior for scrolling through a result set.
*
* @param string $sql The SQL statement to process.
* @param integer $limit The maximum affected rows to set.
* @param integer $offset The affected row offset to set.
*
* @return string The processed SQL statement.
*
* @since 11.1
*/
protected function limit($sql, $limit, $offset)
{
$orderBy = stristr($sql, 'ORDER BY');
if (is_null($orderBy) || empty($orderBy))
{
$orderBy = 'ORDER BY (select 0)';
}
$sql = str_ireplace($orderBy, '', $sql);
$rowNumberText = ',ROW_NUMBER() OVER (' . $orderBy . ') AS RowNumber FROM ';
$sql = preg_replace('/\\s+FROM/', '\\1 ' . $rowNumberText . ' ', $sql, 1);
$sql = 'SELECT TOP ' . $this->limit . ' * FROM (' . $sql . ') _myResults WHERE RowNumber > ' . $this->offset;
return $sql;
}
}