Improve the SQLSRV (MSSQL) database driver

1 files changed, 121 insertions, 164 deletions

diff --git a/system/database/drivers/sqlsrv/sqlsrv_driver.php b/system/database/drivers/sqlsrv/sqlsrv_driver.php
index 6fd52ef70..cdd178261 100644
--- a/system/database/drivers/sqlsrv/sqlsrv_driver.php
+++ b/system/database/drivers/sqlsrv/sqlsrv_driver.php
@@ -1,13 +1,13 @@
-<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.1.6 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Open Software License version 3.0
- * 
+ *
  * This source file is subject to the Open Software License (OSL 3.0) that is
  * bundled with this package in the files license.txt / license.rst.  It is
  * also available through the world wide web at this URL:
@@ -25,8 +25,6 @@
  * @filesource
  */
 
-// ------------------------------------------------------------------------
-
 /**
  * SQLSRV Database Adapter Class
  *
@@ -42,46 +40,46 @@
  */
 class CI_DB_sqlsrv_driver extends CI_DB {
 
-	var $dbdriver = 'sqlsrv';
+	public $dbdriver = 'sqlsrv';
 
 	// The character used for escaping
-	var $_escape_char = '';
+	protected $_escape_char = '';
 
 	// clause and character used for LIKE escape sequences
-	var $_like_escape_str = " ESCAPE '%s' ";
-	var $_like_escape_chr = '!';
+	protected $_like_escape_str = ' ESCAPE \'%s\' ';
+	protected $_like_escape_chr = '!';
 
 	/**
 	 * 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() functions.
 	 */
-	var $_count_string = "SELECT COUNT(*) AS ";
-	var $_random_keyword = ' ASC'; // not currently supported
+	protected $_count_string = 'SELECT COUNT(*) AS ';
+	protected $_random_keyword = ' NEWID()';
 
 	/**
 	 * Non-persistent database connection
 	 *
-	 * @access	private called by the base class
 	 * @return	resource
 	 */
-	function db_connect($pooling = false)
+	public function db_connect($pooling = TRUE)
 	{
 		// Check for a UTF-8 charset being passed as CI's default 'utf8'.
 		$character_set = (0 === strcasecmp('utf8', $this->char_set)) ? 'UTF-8' : $this->char_set;
 
 		$connection = array(
-			'UID'				=> empty($this->username) ? '' : $this->username,
-			'PWD'				=> empty($this->password) ? '' : $this->password,
-			'Database'			=> $this->database,
-			'ConnectionPooling' => $pooling ? 1 : 0,
+			'UID'			=> empty($this->username) ? '' : $this->username,
+			'PWD'			=> empty($this->password) ? '' : $this->password,
+			'Database'		=> $this->database,
+			'ConnectionPooling'	=> $pooling ? 1 : 0,
 			'CharacterSet'		=> $character_set,
-			'ReturnDatesAsStrings' => 1
+			'ReturnDatesAsStrings'	=> 1
 		);
-		
-		// If the username and password are both empty, assume this is a 
+
+		// If the username and password are both empty, assume this is a
 		// 'Windows Authentication Mode' connection.
-		if(empty($connection['UID']) && empty($connection['PWD'])) {
+		if (empty($connection['UID']) && empty($connection['PWD']))
+		{
 			unset($connection['UID'], $connection['PWD']);
 		}
 
@@ -93,10 +91,9 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Persistent database connection
 	 *
-	 * @access	private called by the base class
 	 * @return	resource
 	 */
-	function db_pconnect()
+	public function db_pconnect()
 	{
 		return $this->db_connect(TRUE);
 	}
@@ -109,12 +106,11 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 * Keep / reestablish the db connection if no queries have been
 	 * sent for a length of time exceeding the server's idle timeout
 	 *
-	 * @access	public
 	 * @return	void
 	 */
-	function reconnect()
+	public function reconnect()
 	{
-		// not implemented in MSSQL
+		// Not supported in MSSQL
 	}
 
 	// --------------------------------------------------------------------
@@ -122,10 +118,9 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Select the database
 	 *
-	 * @access	private called by the base class
 	 * @return	resource
 	 */
-	function db_select()
+	public function db_select()
 	{
 		return $this->_execute('USE ' . $this->database);
 	}
@@ -135,14 +130,13 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Set client character set
 	 *
-	 * @access	public
 	 * @param	string
 	 * @param	string
-	 * @return	resource
+	 * @return	bool
 	 */
-	function db_set_charset($charset, $collation)
+	public function db_set_charset($charset, $collation)
 	{
-		// @todo - add support if needed
+		// This is done upon connect
 		return TRUE;
 	}
 
@@ -151,17 +145,13 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Execute the query
 	 *
-	 * @access	private called by the base class
 	 * @param	string	an SQL query
 	 * @return	resource
 	 */
-	function _execute($sql)
+	protected function _execute($sql)
 	{
-		$sql = $this->_prep_query($sql);
-		return sqlsrv_query($this->conn_id, $sql, null, array(
-			'Scrollable'				=> SQLSRV_CURSOR_STATIC,
-			'SendStreamParamsAtExec'	=> true
-		));
+		return sqlsrv_query($this->conn_id, $this->_prep_query($sql), NULL,
+					array('Scrollable' => SQLSRV_CURSOR_STATIC, 'SendStreamParamsAtExec' => TRUE));
 	}
 
 	// --------------------------------------------------------------------
@@ -171,11 +161,10 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 *
 	 * If needed, each database adapter can prep the query string
 	 *
-	 * @access	private called by execute()
 	 * @param	string	an SQL query
 	 * @return	string
 	 */
-	function _prep_query($sql)
+	protected function _prep_query($sql)
 	{
 		return $sql;
 	}
@@ -185,18 +174,12 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Begin Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_begin($test_mode = FALSE)
+	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;
 		}
@@ -204,7 +187,7 @@ class CI_DB_sqlsrv_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);
 
 		return sqlsrv_begin_transaction($this->conn_id);
 	}
@@ -214,18 +197,12 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Commit Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_commit()
+	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;
 		}
@@ -238,18 +215,12 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Rollback Transaction
 	 *
-	 * @access	public
 	 * @return	bool
 	 */
-	function trans_rollback()
+	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 $this->_trans_depth > 0)
 		{
 			return TRUE;
 		}
@@ -262,12 +233,11 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Escape String
 	 *
-	 * @access	public
 	 * @param	string
 	 * @param	bool	whether or not the string will be used in a LIKE condition
 	 * @return	string
 	 */
-	function escape_str($str, $like = FALSE)
+	public function escape_str($str, $like = FALSE)
 	{
 		// Escape single quotes
 		return str_replace("'", "''", $str);
@@ -278,10 +248,9 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Affected Rows
 	 *
-	 * @access	public
-	 * @return	integer
+	 * @return	int
 	 */
-	function affected_rows()
+	public function affected_rows()
 	{
 		return @sqlrv_rows_affected($this->conn_id);
 	}
@@ -293,30 +262,13 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	*
 	* Returns the last id created in the Identity column.
 	*
-	* @access public
-	* @return integer
-	*/
-	function insert_id()
-	{
-		return $this->query('select @@IDENTITY as insert_id')->row('insert_id');
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	* Parse major version
-	*
-	* Grabs the major version number from the
-	* database server version string passed in.
-	*
-	* @access private
-	* @param string $version
-	* @return int16 major version number
+	* @return	int
 	*/
-	function _parse_major_version($version)
+	public function insert_id()
 	{
-		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('SELECT @@IDENTITY AS insert_id');
+		$query = $query->row();
+		return $query->insert_id;
 	}
 
 	// --------------------------------------------------------------------
@@ -324,13 +276,12 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	* Version number query string
 	*
-	* @access public
-	* @return string
+	* @return	string
 	*/
-	function _version()
+	protected function _version()
 	{
 		$info = sqlsrv_server_info($this->conn_id);
-		return sprintf("select '%s' as ver", $info['SQLServerVersion']);
+		return $info['SQLServerVersion'];
 	}
 
 	// --------------------------------------------------------------------
@@ -341,23 +292,25 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 * Generates a platform-specific query string that counts all records in
 	 * the specified database
 	 *
-	 * @access	public
 	 * @param	string
-	 * @return	string
+	 * @return	int
 	 */
-	function count_all($table = '')
+	public function count_all($table = '')
 	{
 		if ($table == '')
-			return '0';
-	
-		$query = $this->query("SELECT COUNT(*) AS numrows FROM " . $this->dbprefix . $table);
-		
-		if ($query->num_rows() == 0)
-			return '0';
-
-		$row = $query->row();
+		{
+			return 0;
+		}
+
+		$query = $this->query('SELECT COUNT(*) AS numrows FROM '.$this->dbprefix.$table);
+		if ($query->num_rows() === 0)
+		{
+			return 0;
+		}
+
+		$query = $query->row();
 		$this->_reset_select();
-		return $row->numrows;
+		return (int) $query->numrows;
 	}
 
 	// --------------------------------------------------------------------
@@ -367,11 +320,10 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query string so that the table names can be fetched
 	 *
-	 * @access	private
-	 * @param	boolean
+	 * @param	bool
 	 * @return	string
 	 */
-	function _list_tables($prefix_limit = FALSE)
+	protected function _list_tables($prefix_limit = FALSE)
 	{
 		return "SELECT name FROM sysobjects WHERE type = 'U' ORDER BY name";
 	}
@@ -383,11 +335,10 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query string so that the column names can be fetched
 	 *
-	 * @access	private
 	 * @param	string	the table name
 	 * @return	string
 	 */
-	function _list_columns($table = '')
+	protected function _list_columns($table = '')
 	{
 		return "SELECT * FROM INFORMATION_SCHEMA.Columns WHERE TABLE_NAME = '".$this->_escape_table($table)."'";
 	}
@@ -399,13 +350,12 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific query so that the column data can be retrieved
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @return	object
 	 */
-	function _field_data($table)
+	protected function _field_data($table)
 	{
-		return "SELECT TOP 1 * FROM " . $this->_escape_table($table);	
+		return 'SELECT TOP 1 * FROM '.$this->_escape_table($table);
 	}
 
 	// --------------------------------------------------------------------
@@ -413,13 +363,18 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * The error message string
 	 *
-	 * @access	private
 	 * @return	string
 	 */
-	function _error_message()
+	protected function _error_message()
 	{
-		$error = array_shift(sqlsrv_errors());
-		return !empty($error['message']) ? $error['message'] : null;
+		$error = sqlsrv_errors();
+		if ( ! is_array($error))
+		{
+			return '';
+		}
+
+		$error = array_shift($error);
+		return isset($error['message']) ? $error['message'] : '';
 	}
 
 	// --------------------------------------------------------------------
@@ -427,13 +382,29 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * The error message number
 	 *
-	 * @access	private
-	 * @return	integer
+	 * @return	string
 	 */
-	function _error_number()
+	protected function _error_number()
 	{
-		$error = array_shift(sqlsrv_errors());
-		return isset($error['SQLSTATE']) ? $error['SQLSTATE'] : null;
+		$error = sqlsrv_errors();
+		if ( ! is_array($error))
+		{
+			return '';
+		}
+		elseif (isset($error['SQLSTATE'], $error['code']))
+		{
+			return $error['SQLSTATE'].'/'.$error['code'];
+		}
+		elseif (isset($error['SQLSTATE']))
+		{
+			return $error['SQLSTATE'];
+		}
+		elseif (isset($error['code']))
+		{
+			return $error['code'];
+		}
+
+		return '';
 	}
 
 	// --------------------------------------------------------------------
@@ -444,26 +415,23 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 * This function adds backticks if the table name has a period
 	 * in it. Some DBs will get cranky unless periods are escaped
 	 *
-	 * @access	private
 	 * @param	string	the table name
 	 * @return	string
 	 */
-	function _escape_table($table)
+	protected function _escape_table($table)
 	{
 		return $table;
-	}	
-
+	}
 
 	/**
 	 * Escape the SQL Identifiers
 	 *
 	 * This function escapes column and table names
 	 *
-	 * @access	private
 	 * @param	string
 	 * @return	string
 	 */
-	function _escape_identifiers($item)
+	public function _escape_identifiers($item)
 	{
 		return $item;
 	}
@@ -476,11 +444,10 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 * This function implicitly groups FROM tables so there is no confusion
 	 * about operator precedence in harmony with SQL standards
 	 *
-	 * @access	public
-	 * @param	type
-	 * @return	type
+	 * @param	array
+	 * @return	string
 	 */
-	function _from_tables($tables)
+	protected function _from_tables($tables)
 	{
 		if ( ! is_array($tables))
 		{
@@ -497,15 +464,14 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific insert string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @param	array	the insert keys
 	 * @param	array	the insert values
 	 * @return	string
 	 */
-	function _insert($table, $keys, $values)
-	{	
-		return "INSERT INTO ".$this->_escape_table($table)." (".implode(', ', $keys).") VALUES (".implode(', ', $values).")";
+	protected function _insert($table, $keys, $values)
+	{
+		return 'INSERT INTO '.$this->_escape_table($table).' ('.implode(', ', $keys).') VALUES ('.implode(', ', $values).')';
 	}
 
 	// --------------------------------------------------------------------
@@ -515,7 +481,6 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific update string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @param	array	the update data
 	 * @param	array	the where clause
@@ -523,16 +488,16 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 * @param	array	the limit clause
 	 * @return	string
 	 */
-	function _update($table, $values, $where)
+	protected function _update($table, $values, $where)
 	{
-		foreach($values as $key => $val)
+		foreach ($values as $key => $val)
 		{
-			$valstr[] = $key." = ".$val;
+			$valstr[] = $key.' = '.$val;
 		}
-	
-		return "UPDATE ".$this->_escape_table($table)." SET ".implode(', ', $valstr)." WHERE ".implode(" ", $where);
+
+		return 'UPDATE '.$this->_escape_table($table).' SET '.implode(', ', $valstr).' WHERE '.implode(' ', $where);
 	}
-	
+
 	// --------------------------------------------------------------------
 
 	/**
@@ -542,13 +507,12 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 * If the database does not support the truncate() command
 	 * This function maps to "DELETE FROM table"
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @return	string
 	 */
-	function _truncate($table)
+	protected function _truncate($table)
 	{
-		return "TRUNCATE ".$table;
+		return 'TRUNCATE '.$table;
 	}
 
 	// --------------------------------------------------------------------
@@ -558,15 +522,14 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific delete string from the supplied data
 	 *
-	 * @access	public
 	 * @param	string	the table name
 	 * @param	array	the where clause
 	 * @param	string	the limit clause
 	 * @return	string
 	 */
-	function _delete($table, $where)
+	protected function _delete($table, $where)
 	{
-		return "DELETE FROM ".$this->_escape_table($table)." WHERE ".implode(" ", $where);
+		return 'DELETE FROM '.$this->_escape_table($table).' WHERE '.implode(' ', $where);
 	}
 
 	// --------------------------------------------------------------------
@@ -576,17 +539,14 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	 *
 	 * Generates a platform-specific LIMIT clause
 	 *
-	 * @access	public
 	 * @param	string	the sql query string
 	 * @param	integer	the number of rows to limit the query to
 	 * @param	integer	the offset value
 	 * @return	string
 	 */
-	function _limit($sql, $limit, $offset)
+	protected function _limit($sql, $limit, $offset)
 	{
-		$i = $limit + $offset;
-	
-		return preg_replace('/(^\SELECT (DISTINCT)?)/i','\\1 TOP '.$i.' ', $sql);		
+		return preg_replace('/(^\SELECT (DISTINCT)?)/i','\\1 TOP '.($limit + $offset).' ', $sql);
 	}
 
 	// --------------------------------------------------------------------
@@ -594,18 +554,15 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 	/**
 	 * Close DB Connection
 	 *
-	 * @access	public
 	 * @param	resource
 	 * @return	void
 	 */
-	function _close($conn_id)
+	protected function _close($conn_id)
 	{
 		@sqlsrv_close($conn_id);
 	}
 
 }
 
-
-
-/* End of file mssql_driver.php */
-/* Location: ./system/database/drivers/mssql/mssql_driver.php */
\ No newline at end of file
+/* End of file sqlsrv_driver.php */
+/* Location: ./system/database/drivers/sqlsrv/sqlsrv_driver.php */