Merge upstream branch

1 files changed, 90 insertions, 117 deletions

diff --git a/system/database/drivers/mssql/mssql_driver.php b/system/database/drivers/mssql/mssql_driver.php
index f60ec8168..b4a1af7ba 100644
--- a/system/database/drivers/mssql/mssql_driver.php
+++ b/system/database/drivers/mssql/mssql_driver.php
@@ -43,33 +43,57 @@ class CI_DB_mssql_driver extends CI_DB {
 	public $dbdriver = 'mssql';
 
 	// The character used for escaping
-	protected $_escape_char = '';
+	protected $_escape_char = '"';
 
-	// clause and character used for LIKE escape sequences
-	protected $_like_escape_str = " ESCAPE '%s' ";
-	protected $_like_escape_chr = '!';
+	protected $_random_keyword = ' NEWID()';
 
-	/**
-	 * The syntax to count rows is slightly different across different
-	 * database engines, so this string appears in each driver and is
-	 * used for the count_all() and count_all_results() methods.
+	// MSSQL-specific properties
+	protected $_quoted_identifier = TRUE;
+
+	/*
+	 * Constructor
+	 *
+	 * Appends the port number to the hostname, if needed.
+	 *
+	 * @param	array
+	 * @return	void
 	 */
-	protected $_count_string = 'SELECT COUNT(*) AS ';
-	protected $_random_keyword = ' NEWID()';
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if ( ! empty($this->port))
+		{
+			$this->hostname .= (DIRECTORY_SEPARATOR === '\\' ? ',' : ':').$this->port;
+		}
+	}
+
+	// --------------------------------------------------------------------
 
 	/**
 	 * Non-persistent database connection
 	 *
+	 * @param	bool
 	 * @return	resource
 	 */
-	public function db_connect()
+	public function db_connect($persistent = FALSE)
 	{
-		if ($this->port != '')
+		$this->conn_id = ($persistent)
+				? @mssql_pconnect($this->hostname, $this->username, $this->password)
+				: @mssql_connect($this->hostname, $this->username, $this->password);
+
+		if ( ! $this->conn_id)
 		{
-			$this->hostname .= ','.$this->port;
+			return FALSE;
 		}
 
-		return @mssql_connect($this->hostname, $this->username, $this->password);
+		// Determine how identifiers are escaped
+		$query = $this->query('SELECT CASE WHEN (@@OPTIONS | 256) = @@OPTIONS THEN 1 ELSE 0 END AS qi');
+		$query = $query->row_array();
+		$this->_quoted_identifier = empty($query) ? FALSE : (bool) $query['qi'];
+		$this->_escape_char = ($this->_quoted_identifier) ? '"' : array('[', ']');
+
+		return $this->conn_id;
 	}
 
 	// --------------------------------------------------------------------
@@ -81,12 +105,7 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	public function db_pconnect()
 	{
-		if ($this->port != '')
-		{
-			$this->hostname .= ','.$this->port;
-		}
-
-		return @mssql_pconnect($this->hostname, $this->username, $this->password);
+		return $this->db_connect(TRUE);
 	}
 
 	// --------------------------------------------------------------------
@@ -106,7 +125,7 @@ class CI_DB_mssql_driver extends CI_DB {
 
 		// Note: The brackets are required in the event that the DB name
 		// contains reserved characters
-		if (@mssql_select_db('['.$database.']', $this->conn_id))
+		if (@mssql_select_db($this->escape_identifiers($database), $this->conn_id))
 		{
 			$this->database = $database;
 			return TRUE;
@@ -121,7 +140,7 @@ class CI_DB_mssql_driver extends CI_DB {
 	 * Execute the query
 	 *
 	 * @param	string	an SQL query
-	 * @return	resource
+	 * @return	mixed	resource if rows are returned, bool otherwise
 	 */
 	protected function _execute($sql)
 	{
@@ -137,13 +156,8 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	public function trans_begin($test_mode = FALSE)
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -151,10 +165,9 @@ class CI_DB_mssql_driver extends CI_DB {
 		// Reset the transaction failure flag.
 		// If the $test_mode flag is set to TRUE transactions will be rolled back
 		// even if the queries produce a successful result.
-		$this->_trans_failure = ($test_mode === TRUE) ? TRUE : FALSE;
+		$this->_trans_failure = ($test_mode === TRUE);
 
-		$this->simple_query('BEGIN TRAN');
-		return TRUE;
+		return $this->simple_query('BEGIN TRAN');
 	}
 
 	// --------------------------------------------------------------------
@@ -166,19 +179,13 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	public function trans_commit()
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
 
-		$this->simple_query('COMMIT TRAN');
-		return TRUE;
+		return $this->simple_query('COMMIT TRAN');
 	}
 
 	// --------------------------------------------------------------------
@@ -190,19 +197,13 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	public function trans_rollback()
 	{
-		if ( ! $this->trans_enabled)
-		{
-			return TRUE;
-		}
-
 		// When transactions are nested we only begin/commit/rollback the outermost ones
-		if ($this->_trans_depth > 0)
+		if ( ! $this->trans_enabled OR $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
 
-		$this->simple_query('ROLLBACK TRAN');
-		return TRUE;
+		return $this->simple_query('ROLLBACK TRAN');
 	}
 
 	// --------------------------------------------------------------------
@@ -232,7 +233,7 @@ class CI_DB_mssql_driver extends CI_DB {
 		// escape LIKE condition wildcards
 		if ($like === TRUE)
 		{
-			$str = str_replace(
+			return str_replace(
 				array($this->_like_escape_chr, '%', '_'),
 				array($this->_like_escape_chr.$this->_like_escape_chr, $this->_like_escape_chr.'%', $this->_like_escape_chr.'_'),
 				$str
@@ -265,28 +266,13 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	public function insert_id()
 	{
-		$ver = self::_parse_major_version($this->version());
-		$sql = ($ver >= 8 ? "SELECT SCOPE_IDENTITY() AS last_id" : "SELECT @@IDENTITY AS last_id");
-		$query = $this->query($sql);
-		$row = $query->row();
-		return $row->last_id;
-	}
+		$query = version_compare($this->version(), '8', '>=')
+			? 'SELECT SCOPE_IDENTITY() AS last_id'
+			: 'SELECT @@IDENTITY AS last_id';
 
-	// --------------------------------------------------------------------
-
-	/**
-	 * Parse major version
-	 *
-	 * Grabs the major version number from the
-	 * database server version string passed in.
-	 *
-	 * @param	string	$version
-	 * @return	int	major version number
-	 */
-	protected function _parse_major_version($version)
-	{
-		preg_match('/([0-9]+)\.([0-9]+)\.([0-9]+)/', $version, $ver_info);
-		return $ver_info[1]; // return the major version b/c that's all we're interested in.
+		$query = $this->query($query);
+		$query = $query->row();
+		return $query->last_id;
 	}
 
 	// --------------------------------------------------------------------
@@ -304,35 +290,6 @@ class CI_DB_mssql_driver extends CI_DB {
 	// --------------------------------------------------------------------
 
 	/**
-	 * "Count All" query
-	 *
-	 * Generates a platform-specific query string that counts all records in
-	 * the specified database
-	 *
-	 * @param	string
-	 * @return	string
-	 */
-	public function count_all($table = '')
-	{
-		if ($table == '')
-		{
-			return 0;
-		}
-
-		$query = $this->query($this->_count_string.$this->protect_identifiers('numrows').' FROM '.$this->protect_identifiers($table, TRUE, NULL, FALSE));
-		if ($query->num_rows() == 0)
-		{
-			return 0;
-		}
-
-		$row = $query->row();
-		$this->_reset_select();
-		return (int) $row->numrows;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * List table query
 	 *
 	 * Generates a platform-specific query string so that the table names can be fetched
@@ -342,16 +299,17 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	protected function _list_tables($prefix_limit = FALSE)
 	{
-		$sql = "SELECT name FROM sysobjects WHERE type = 'U' ORDER BY name";
+		$sql = 'SELECT '.$this->escape_identifiers('name')
+			.' FROM '.$this->escape_identifiers('sysobjects')
+			.' WHERE '.$this->escape_identifiers('type')." = 'U'";
 
-		// for future compatibility
-		if ($prefix_limit !== FALSE AND $this->dbprefix != '')
+		if ($prefix_limit !== FALSE AND $this->dbprefix !== '')
 		{
-			//$sql .= " LIKE '".$this->escape_like_str($this->dbprefix)."%' ".sprintf($this->_like_escape_str, $this->_like_escape_chr);
-			return FALSE; // not currently supported
+			$sql .= ' AND '.$this->escape_identifiers('name')." LIKE '".$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
 		}
 
-		return $sql;
+		return $sql.' ORDER BY '.$this->escape_identifiers('name');
 	}
 
 	// --------------------------------------------------------------------
@@ -381,7 +339,7 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	protected function _field_data($table)
 	{
-		return "SELECT TOP 1 * FROM ".$table;
+		return 'SELECT TOP 1 * FROM '.$this->protect_identifiers($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -414,12 +372,7 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	protected function _from_tables($tables)
 	{
-		if ( ! is_array($tables))
-		{
-			$tables = array($tables);
-		}
-
-		return implode(', ', $tables);
+		return is_array($tables) ? implode(', ', $tables) : $tables;
 	}
 
 	// --------------------------------------------------------------------
@@ -513,9 +466,30 @@ class CI_DB_mssql_driver extends CI_DB {
 	 */
 	protected function _limit($sql, $limit, $offset)
 	{
-		$i = $limit + $offset;
+		// As of SQL Server 2012 (11.0.*) OFFSET is supported
+		if (version_compare($this->version(), '11', '>='))
+		{
+			return $sql.' OFFSET '.(int) $offset.' ROWS FETCH NEXT '.(int) $limit.' ROWS ONLY';
+		}
+
+		$limit = $offset + $limit;
+
+		// As of SQL Server 2005 (9.0.*) ROW_NUMBER() is supported,
+		// however an ORDER BY clause is required for it to work
+		if (version_compare($this->version(), '9', '>=') && $offset && ! empty($this->qb_orderby))
+		{
+			$orderby = 'ORDER BY '.implode(', ', $this->qb_orderby);
+
+			// We have to strip the ORDER BY clause
+			$sql = trim(substr($sql, 0, strrpos($sql, 'ORDER BY '.$orderby)));
+
+			return 'SELECT '.(count($this->qb_select) === 0 ? '*' : implode(', ', $this->qb_select))." FROM (\n"
+				.preg_replace('/^(SELECT( DISTINCT)?)/i', '\\1 ROW_NUMBER() OVER('.$orderby.') AS '.$this->escape_identifiers('CI_rownum').', ', $sql)
+				."\n) ".$this->escape_identifiers('CI_subquery')
+				."\nWHERE ".$this->escape_identifiers('CI_rownum').' BETWEEN '.((int) $offset + 1).' AND '.$limit;
+		}
 
-		return preg_replace('/(^\SELECT (DISTINCT)?)/i','\\1 TOP '.$i.' ', $sql);
+		return preg_replace('/(^\SELECT (DISTINCT)?)/i','\\1 TOP '.$limit.' ', $sql);
 	}
 
 	// --------------------------------------------------------------------
@@ -523,15 +497,14 @@ class CI_DB_mssql_driver extends CI_DB {
 	/**
 	 * Close DB Connection
 	 *
-	 * @param	resource
 	 * @return	void
 	 */
-	protected function _close($conn_id)
+	protected function _close()
 	{
-		@mssql_close($conn_id);
+		@mssql_close($this->conn_id);
 	}
 
 }
 
 /* End of file mssql_driver.php */
-/* Location: ./system/database/drivers/mssql/mssql_driver.php */
+/* Location: ./system/database/drivers/mssql/mssql_driver.php */
\ No newline at end of file