Merge pull request #5243 from rosseti/fix/pdo-dblib-sqlserver-version

Fix for DBLIB subdriver to get the right version number of SQL Server.
diff --git a/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php b/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
index e9226c3..b9b86f7 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
@@ -334,4 +334,20 @@
 		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
 	}
 
+	// --------------------------------------------------------------------
+
+	/**
+	 * Database version number
+	 *
+	 * @return      string
+	 */
+	public function version()
+	{
+		if (isset($this->data_cache['version']))
+		{
+			return $this->data_cache['version'];
+		}
+
+		return $this->data_cache['version'] = $this->conn_id->query("SELECT SERVERPROPERTY('ProductVersion') AS ver")->fetchColumn(0);
+	}
 }