The Young DBA

Enterprise Systems and IT Application can be categories in two types OLTP and OLAP . In General Terms OLTP is day to day Record Keeping of any organization and OLAP is the Historical Data of Warehouse..   OLTP (On-line Transaction Processing)   is characterized by a large number of transactions (INSERT, UPDATE, DELETE). The main emphasis for OLTP systems is put on very fast query processing, maintaining data integrity in multi-access environments and an effectiveness measured by number of transactions per second. In OLTP database there is detailed and current data, and schema used to store transactional databases is the entity model (usually 3NF) OLAP (On-line Analytical Processing)   is characterized by relatively low volume of transactions. Queries are often very complex and involve aggregations(DISTINCT,GROUP BY,SUM,COUNT ..). For OLAP systems a response time is an effectiveness measure. OLAP applications are widely used by Data Mining techniques. In OLAP database ther

Dear Friends , Last week I was doing Database Re-Engineering of our few Legacy Applications. Actually Re-engineering is a set of activities that are carried out to re-structure a Legacy System to a new system with better functionalities and conform to the hardware and software quality constraint. I tested 3 Tools for Data-Modeling for this process. (1) Toad Data Modeler 4.1 (2) Microsoft Visio and (3) SSMS 2008 . Data Modeling is a process used to define and analyze data requirements needed to support the business processes within the scope of corresponding information systems in organizations. All are the good software for Data-modeling but I liked all time favorite SQL Server Management Studio Relationship Diagrams simple-easy, free and having good options.. A little formatting in SSMS database diagrams editor As more tables will be added, these may not be arranged for easy viewing. To change the arrangement of the diagrams you can right click in the

I n SQL Server, much like other services with users, login accounts can be enabled or disabled. An enabled login can be authenticated and allowed access to database resources. A disabled login is not allowed to establish a connection to the SQL Server instance. For example, let's create a login called  sumank . CREATE LOGIN sumank WITH PASSWORD = 'ipl5@2012' ,DEFAULT_DATABASE = AdventureWorks USE AdventureWorks; CREATE USER sumank In the first statement, the sumank login was created with a fairly complex password and a default database of AdventureWorks. Afterward, we switch to the AdventureWorks database and create a new user for the database. If we attempt to login to SQL Server using these credentials, we can. Next let's disable the login with the following statement. ALTER LOGIN sumank DISABLE If someone attempts to login to SQL Server using the  sumank    login, the connection attempt is rejected and Error 18470 is returned - &q

SQL Server Versions and Code Names :- Version Year Release Name Codename 1.0 ( OS/2 ) 1989 SQL Server 1.0 (16bit) - 1.1 ( OS/2 ) 1991 SQL Server 1.1 (16bit) - 4.21 ( WinNT ) 1993 SQL Server 4.21 SQLNT 6.0 1995 SQL Server 6.0 SQL95 6.5 1996 SQL Server 6.5 Hydra 7.0 1998 SQL Server 7.0 Sphinx - 1999 SQL Server 7.0 OLAP  Tools Plato 8.0 2000 SQL Server 2000 Shiloh 8.0 2003 SQL Server 2000 64-bit Edition Liberty 9.0 2005 SQL Server 2005 Yukon 10.0 2008 SQL Server 2008 Katmai 10.25 2010 SQL Azure DB CloudDB 10.5 2010 SQL Server 2008 R2 Kilimanjaro (aka KJ) 11.0 2012 SQL Server 2012 Denali Version with Service Packs... SQL Server 2012 11.0.2316 SQL Server 2012 CU1 12 Apr 2012 11.0.2100.6 SQL Server 2012 RTM 7 Mar 2012 SQL Server 2008 R2 10.50.2811 SQL Server 2008 R2 SP1 CU6 16 Apr 2012 10.50.2806 SQL Server 2008 R2 SP1 CU5 22 Feb 2012 10.50.2796 SQL Server 2008 R2 SP1 CU4 9 Jan 2012 10.50.2789.0 SQL Server 2008 R2 SP1 CU3 17 Oct 2011 10.50.2772.0 SQL