Data Recovery from databases

Data recovery is the process of restoring data that has been lost, accidentally deleted, corrupted or made inaccessible for any reason. In enterprise information technology (IT), data recovery typically refers to the restoration of data to a desktop, laptop, server, or external storage system from a backup.

A recovery-only file restore can be useful in the following situation:

A database is restored piecemeal. After restore of the primary file group is complete, one or more of the unrestored files are consistent with the new database state, perhaps because it has been read-only for some time. These files only have to be recovered; data copying is unnecessary.

A recovery-only restore operation brings the data in the offline file group online; no data-copy, redo, or undo phase occurs. The ability to restore databases from valid backups is a vital part of ensuring business continuity. Backup integrity and restorations are an important piece of the IT Governance Institute’s IT Control Objectives for Sarbanes-Oxley, 2nd Edition. In many instances, IT auditors merely confirm whether backups are being performed either to disk or to tape, without considering the integrity or viability of the backup media.

One of the key responsibilities of a database administrator (DBA) is to prepare for the possibility of media, hardware and software failure as well as to recover databases during a disaster. Should any of these failures occur, the major objective is to ensure that the database is available to users within an acceptable time period, while ensuring that there is no loss of data. DBAs should evaluate their preparedness to respond effectively to such situations by answering the following questions:

  • How confident is the DBA that the data on which the company business depends are backed up successfully and that the data can be recovered from these backups within the permissible time limits, per a service level agreement (SLA) or recovery time objective, as specified in the organization’s disaster recovery plan?

 

  • Has the DBA taken measures to draft and test the procedures to protect as well as recover the databases from numerous types of failures?

The following is a checklist for database backup and recovery procedures

  • Develop a comprehensive backup plan.
  • Perform effective backup management.
  • Perform periodic databases restore testing.
  • Have backup and recovery SLAs drafted and communicated to all stakeholders.
  • Have the disaster recovery plan (DRP) database portion drafted and documented.
  • Keep your knowledge and know-how on database and OS backup and recovery tools up to date.

A data recovery company in Houtston Texas has developed some advanced sql recovery techniques for the seriously damaged cases, they can be found at http://www.datanalyzers.com/houston-data-recovery/  Also, a well recommendable commercial sql data recovery software can be found at SQL Database Recovery Software

Either way I would recommend creating a backup copy before sending out the database to a specialized data recovery lab or even before attempting a do it yourself recovery (DIY) with some of the recomended software products. One of the main problems is that commercial sql recovery software will attempt to find corruptions within pages and if the application can not repair the page within the record, it will simply delete the page and record entry. This can sometimes leave the database in a state that is functional, but neverthelsess the relations of the database tables can produce undesired results when your front ent application attempts to query certain database records.

 

 

Computer forensics really do solve crimes

computer-forensics

Computer forensics integrates the fields of computer science and law to investigate crime. For digital evidence to be legally admissible in court, investigators must follow proper legal procedures when recovering and analyzing data from computer systems. Unfortunately, laws written before the era of computer forensics are often outdated and cannot adequately assess the techniques used in a computer system search. The inability of the law to keep pace with technological advancements may ultimately limit the use of computer forensics evidence in court.

Privacy advocates are growing especially concerned that computer searches may be a breach of a suspect’s human rights. Furthermore, as methods for encryption and anonymity grow more advanced, technology may be abused by helping criminals hide their actions. Ultimately, the role of technology in computer forensics may not reach its full potential due to legal boundaries and potential malicious intentions.

Forensic science is the scientific method of gathering and examining information about the past which is then used in a court of law. The word forensic comes from the Latin forēnsis, meaning “of or before the forum.” In Roman times, a criminal charge meant presenting the case before a group of public individuals in the forum. Both the person accused of the crime and the accuser would give speeches based on their sides of the story. The case would be decided in favor of the individual with the best argument and delivery. This origin is the source of the two modern usages of the word forensic – as a form of legal evidence and as a category of public presentation. In modern use, the term forensics in the place of forensic science can be considered correct, as the term forensic is effectively a synonym for legal or related to courts.

forensic-figerprint

Forensic investigations seek to uncover, analyze and preserve evidence to be used in criminal proceedings. As technology has become increasingly prevalent in everyday life, investigations have spread to computers, telephones and other electronics.

Computer forensics has been indispensable in the conviction of many well-known criminals, including terrorists, sexual predators, and murderers. Terrorist organizations may use the Internet to recruit members, and sexual predators may use social networking sites to stalk potential victims. However, most criminals fail to cover their tracks when using technology to implement their crimes. They fail to realize that computer files and data remain on their hard drive even when deleted, allowing investigators to track their criminal activity. Even if criminals delete their incriminating files, the data remains in a binary format due to “data remanence” or the residual representation of data. File deletion merely renames the file and hides it from the user; the original file can still be recovered.

Microsoft SQL Server vs. Oracle Database

Any business that needs a lot of data and information for their daily business activities must consider the high availability capabilities for the database. Data is a sensitive and highly critical asset of any organization and it needs to be handled with proper care. There are several databases including MySQL, Sybase and Microsoft access. But for several years we have had a constant battle between fans of the Microsoft SQL Server and those of the Oracle Server. Of course most fans argue from the point of perception of functionality but that is not the only thing you ought to consider before making a choice. But let’s now crack out the nut and see which one is better in what aspects. Let us look at a closer analysis of the Microsoft SQL Server vs. Oracle Database:

  1. Language

One of the most fundamental differences between the Microsoft SQL Server and the Oracle Database relational database management systems is the language that they use.

Even though both of them have the Structured Query Language or SQL, Microsoft uses the T-SQL or Transact SQL; which is an extension of the SQL that was originally developed by Sybase before being used by Microsoft. On the other hand, Oracle uses the Procedural Language/SQL or PL/SQL. In other words, both sets of servers use different dialects or flavors of the SQL but the languages have different capabilities and syntax.

The main difference between both sets of languages, however, is the manner in which they handle stored procedures, variables and the in-built functions. The Oracle PL/SQL easily groups procedures into different packages—something that the MS SQL Server cannot handle.

  1. Organization of Objects of the Database

The MS SQL Server performs the important function of organizing all objects including procedures, views and tables by the names of the database. The users are then assigned a login which is granted direct access to a very specific database along with its objects. Each database also contains an unshared, private disk file on the server.

On the other hand, the Oracle Database has all the database objects grouped according to schemas that are actually a subset of a collection of database objects. All the database objects are normally shared among all the users and schemas. However, the sharing capability is limited to some specific tables and schemas through the requirement of certain permissions and roles.

  1. Transaction Control

One of the biggest differences between the Oracle Database and the MS SQL Server is the power of transaction control. For your understanding of this aspect, a transaction will be defined as a group of tasks or operations that ought to be treated as a single unit. In other words, a collection of various SQL queries modify records so that all are able to get updated at the same time. For instance, if there is a failure of updating one of the records then all the records should not get updated at all.

The MS SQL, by default, executes and commits each task or command individually. Therefore, it is impossible or difficult to roll back the changes if any error is encountered in the process. These are commands in the MS SQL:

  • The “Begin Transaction” command is used to indicate the commencement of a transaction
  • The “Commit” command is used to end a transaction and write changed data or information to a disk
  • The “Rollback” command allows for protection against incidences of data corruption when used properly in the aspect of error handling. This command also discards any changes that may have been made is a particular transaction block. The user cannot roll back any other information apart from what the “Commit” command can do.

On the other hand, every new database is handled as a new transaction in the Oracle Server. When commands and queries are issued, the changes are only effected in the memory and nothing else is committed until a “commit” statement is issued. Once the “commit” command has been executed, the next command is only used to commence the process once again. Therefore, this gives the handler greater flexibility that assists in controlling errors as well.

  1. Operating System

While the MS SQL Server is executed on the Windows operating system, the Oracle Database can be executed on several operating systems including Windows, Linux, z/OS, UNIX and Mac OS X.

  1. Features

Both the MS SQL and the Oracle Servers have similar principal features including referential integrity, Unicode, transactions and ACID.

  1. Architecture

Both servers use the same architecture which offers numerous advantages to the user: the relational model.

  1. Access Control

Both servers share various aspects of access control including audit procedures, security certifications, native network encryption, resource limit controls, password complexity rules, brute-force protection and enterprise directory compatibility. However, the MS SQL Server has additional access controls including separation of duties, running unprivileged and patch access that make it function much better.

  1. Database Capabilities

Both servers share numerous database capabilities including the except function, blobs and clobs, the union function, windowing functions, outer joins, merge joins, intersects, inner selects and inner joins. These improve the performance of both servers.

  1. Indexes

Both the MS SQL Server and the Oracle Database indexes include spatial, partial, full-text and expression components. However, the Oracle Database has additional indexes including the hash, reverse and R-/R+ Tree that makes its performance better in this area. sql-oracle

  1. Support Options

Users of the MS SQL Server can seek assistance through a Blog and various Forums while Oracle Database users can only seek assistance through various forums.

  1. Cost

The MS SQL Server has always been cheaper as compared to the Oracle Server. Therefore, this is a better option in case you are factoring in your financial budget.

Conclusion

From the discussion above, it is very clear whether there is a particular kind of server you can lean. Both servers are good. However, the best option depends on your business database requirements. You can seek advice from our database experts before making an informed decision today.

 

 

About the Author: Sean McCown is a renowned database expert who is knowledgeable in multiple aspects of Information Technology and Computer Science. He was first involved with the SQL Server in 1995 when he started working for Oracle. Since then, he has worked with several high-transaction databases that have crossed the bridge to become popular options in the market. Having served as an editor and sole database expert at the InfoWorld Magazine, this means that he has expert knowledge about the MS SQL Server, Sybase, DB2 and many other servers out there. As a versatile researcher, he has also written for SQLServerCentral.com, SQL Server Standard, SQL Server Magazine and SSWUG. His prime areas of concentration include reviews, vendor products and industry analysis

The Best Anti-Virus Computer Programs

The best things in life are free. As this is the case, people will often want to use a free anti-virus program, instead of buying a paid program. A number of anti-virus vendors will make free antivirus software available for SOHO and home users. If you are interested in getting the best anti-virus computer [programs that are free, you will need to have a little information on each. This way, you will be able to know the ones or one that will serve your needs. Take note that it will only be effective if it can keep your computer safe from spyware, viruses and other malware. The following is a list of the top five best anti-virus software that are actually free.

 

Avira

Avira AntiVir Personal is leading in the list because of the number of positive reviews /comments it has received from its users. By 2011, more than 60% of voters on the reader’s Choice Awards chose this anti-virus. With such numbers, it is clear that the program is quite effective and popular among users. Apart from the awards, Avira routinely nabs some of the highest scores from other anti-virus testing agencies such as AV-Test.org.

 

AVG Free Edition

AVG (the free edition) is a classic and one of the leading and longest running free anti-virus packages for computers. It may be also the smallest anti-virus scanner to be tested, since it runs on 4 processes and installs 30Mb of files. It is quite popular because it is effective in older personal computers that may not meet the system requirements of modern anti-virus programs.

Microsoft Security Essentials

One of the reasons that Microsoft Security Essentials has earned its spot is that it has consistently performed admirably on a number of third-party anti-virus detection tests and certifications. The added advantage is that it is not only free for home use, but also for small business that has a maximum of ten computers to protect. Microsoft Security Essentials runs on Windows 7, Vista and XP. Take note that it can only be installed on genuine Windows installations.

 

Avast Home Edition

The fact that Avast offers standard scanning gives it a spot on being one of the best free anti-virus. The home addition also provides system scan during bootup. Such an option is effective as it greatly increases the chances of removing any stubborn infectors. This is the case for those that utilise resuscitators to foil any removal attempts. The Home edition is available for free downloads on the developer software, and it can support virtually any Windows platform.

 

Panda Cloud

The Panda Cloud anti-virus is unique as it is not only among the best free anti-virus programs, but it is also the only one that offers free cloud-based scanner. It basically takes off the processing from your PC, which will give you a more proactive, faster and lighter anti-virus protection. Additionally, you can upgrade to the Pro version, for a very low price, and gain additional features which include 24/7 tech support.

 

All these are great anti-virus programs that you can choose form. You will however determine the best by knowing what you need and what seems effective to you. Reading reviews of each can give you a better understanding of the programs. Alternatively, you can download and try each anti-virus before you make a decision.