Blogs

SBS 2008 VPN Error 649

By Krystian Zieja on August 27, 2009 - 15:30

VPN connection to company network is a very common requirement. It allows mobile users to connect to corporate network. By default in Small Business Server 2008 users are not allowed to connect to VPN. When they try to connect to VPN server they receive Error 649: The account does not have permission to dial in. There are many solutions to that problem I will present the simplest, which is based on Role Management.

Sql Server Exporting Data with BCP

By Krystian Zieja on August 22, 2009 - 21:53

BCP is one of the oldest tools you can find in current version of Sql Server, Microsoft started releasing it with early versions of Sql Server. It is designed to perform fast import and export operations. BCP is considered as a lightweight solution for import and export operations, if you need to perform transformations or error handling you should use Sql Server Integration Services (SSIS) instead. This blog post will present the basic ways how to export data from Sql Server database using BCP.

Configure Database Mail in Sql Server 2008

By Krystian Zieja on August 2, 2009 - 23:50

Database Mail in Sql Server 2008 enables sending outbound mail messages. Although the primary use of Database Mail is to send alert messages to administrators, it can also be used to send results of the query, or in Transact - SQL code. Database Mail uses the Simple Mail Transport Protocol (SMTP) to transmit mail messages. It is important to remember that messages are sent by Sql Server Agent, so if it is not running the messages will be accumulated in msdb database and sent when Agent will be started.

How to install PowerShell on Windows Server 2008

By Krystian Zieja on August 2, 2009 - 18:17

Windows PowerShell is a command line and shell scripting language that helps IT specialist in managing their Windows infrastructure. Although PowerShell ships with all versions of Windows Server 2008, it is not installed by default. This blog post will describe the steps you need to follow to install it.

Killing Sessions in Oracle

By Krystian Zieja on July 20, 2009 - 00:27

Sometimes Oracle Database Administrators needs to kill a sessions in Oracle Database. The best way to do it is to ALTER SYSTEM KILL SESSION statement. To use this statement we must provide SID and SERIAL# of the session we are going to kill.

Managing Redo Logs in Oracle

By Krystian Zieja on July 19, 2009 - 13:25

Redo Log Files are crucial for recovery in case of instance failure. Today I will show a bunch of commands how to manage them in Oracle Database. You can find more details on architecture of Redo Log Files in previous post How to multiplex Redo Logs in Oracle

How to multiplex Redo Logs in Oracle

By Krystian Zieja on July 18, 2009 - 18:20

Redo Log files records every change made by users. This guarantees that we will not lose any change, even if it was not written in Data Files due to instance failure. Oracle organizes Redo Logs in Redo Log Groups. Oracle requires at least two Redo Log Groups, each with at least one Redo Log Files to operate. Redo Logs are the most crucial component for recovery operations in case of instance failure, which means that Database Administrators should protect them well. All Redo Log Files in one Redo Log Group are identical. Having this in mind leads to that the best method of protecting Redo Log Files is to create multiple Redo Log Files in each Redo Log Group and put each Redo Log file from the same group on different physical disk. Multiplexing prevents from losing just one copy of the Redo Log File. When Redo Log Files are multiplexed the Log Writer Process (LGWR) writes simultaneously to all members of Redo Log Group.

How to multiplex Control Files in Oracle

By Krystian Zieja on July 17, 2009 - 16:03

Control File is a physical component of every Oracle Database, it is a small binary file, which records database structure. Control File includes information like database name, name and location of data files and redo log files, database creation timestamp, current log sequence number, checkpoint information. Additionally if we use RMAN for backup and we do use RMAN catalog, information about RMAN backups is stored in control file. Oracle Database requires at least one Control File to operate. Control Files must be accessible all the time the database is open.

Sql Server Error: 18452 Login failed for user

By Krystian Zieja on July 8, 2009 - 11:21

This one of the most common errors you can find on Sql Server or ASP.NET forums is Error 18452 Login failed for user. There are three causes, which could trigger that error:

  1. User tried to login using Sql Server Authentication but server allows only for Windows Authentication
  2. User tried to login using Sql Server authentication, but the login does not exist in Sql Server
  3. User tried to login using Windows Authentication, but the login is unrecognized Windows Principal

How to get procedure code in Oracle

By Krystian Zieja on July 7, 2009 - 01:16

How to get procedure code in Oracle
Frequently we need to find the procedure code, without using any developers’ tools like SQL Developer or TOAD. The easiest way to get the code is to use USER_SOURCE or DBA_SOURCE views or DBMS_METADATA PL/SQL Package.