Thursday, July 23, 2009

Database transaction

A database transaction comprises a unit of work performed within a database management system (or similar system) against a database, and treated in a coherent and reliable way independent of other transactions. Transactions in a database environment have two main purposes:

1. To provide reliable units of work that allow correct recovery from failures and keep a database consistent even in cases of system failure, when execution stops (completely or partially) and many operations upon a database remain uncompleted, with unclear status.
2. To provide isolation between programs accessing a database concurrently. Without isolation the programs' outcomes are typically erroneous.

A database transaction, by definition, must be atomic, consistent, isolated and durable. Database practitioners often refer to these properties of database transactions using the acronym ACID.

Transactions provide an "all-or-nothing" proposition, stating that each work-unit performed in a database must either complete in its entirety or have no effect whatsoever. Further, the system must isolate each transaction from other transactions, results must conform to existing constraints in the database, and transactions that complete successfully must get written to durable storage.

Thursday, July 09, 2009

NetApp Named MS 2009 Storage Solutions Partner

NetApp has been named the Microsoft 2009 Partner of the Year, in the advanced infrastructure, storage solutions category. NetApp was chosen out of an international field of top Microsoft partners for delivering market-leading customer solutions for Microsoft Hyper-V environments.

NetApp was chosen on its partnership with Microsoft and complete solutions that help reduce customers' costs, maximize storage efficiency, and improve availability in virtual environments. With NetApp, Microsoft customers can reduce the amount of storage they need by at least 50 percent when they also use NetApp technologies such as thin provisioning and deduplication, the company said.

NetApp utilizes a variety of Windows Server platform technologies to improve storage system management and streamline backup, recovery, and remote replication in Windows Server 2008 Hyper-V environments. In addition, tight integration with the Microsoft System Center family of products and additional application-integrated NetApp products help maximize uptime for a wide variety of application environments, including Microsoft Exchange Server, SQL Server, and SharePoint Server. Since NetApp storage solutions are tightly integrated with Microsoft's technologies, customers are backed by NetApp's global customer support infrastructure, which integrates Microsoft Premier Support.

"We are very excited about working with NetApp to deliver innovative end-to-end solutions to our joint customers. The combination of our technology with NetApp's storage solutions gives our customers the tools they need to improve efficiency, reduce costs, and drive their businesses forward," said Kim Akers, General Manager (Global Partner Team), Microsoft.

Rajesh Janey, President (Sales), India & SAARC, NetApp, said, "Being chosen as Microsoft's Storage Partner of the Year is a great honor for NetApp. While this award establishes NetApp as the leading storage solutions provider for Microsoft virtualization customers, more than anything it underlines the customer success our partnership and close collaboration has delivered."

Wednesday, July 01, 2009

Native MySQL Storage Engines

The MySQL offers a number of within developed storage engines that are well-suited for data warehouses, with the mainly popular being the evasion MyISAM storage engine. The MyISAM engine delivers rapid data loading capabilities, fast study times, and much more for data warehousing users. Typical MyISAM support for data warehouse volumes range up to 1TB contentedly. MySQL offers other storage engines that can also be used for data warehousing as well. MySQL supports these key data warehousing features:

  • Data/Index partitioning (range, hash, key, list, composite) in MySQL 5.1 and above
  • No practical storage limits with automatic storage management
  • Built-in Replication
  • Strong indexing support (B-tree, fulltext, clustered, hash, GIS)
  • Multiple, configurable data/index caches
  • Pre-loading of data into caches
  • Unique query cache (caches result set + query; not just data)
  • Parallel data load
  • Multi-insert DML
  • Read-only tables
  • Cost-based optimizer
  • Wide platform support

Infobright offers a storage engine for the MySQL Server that is tailor-made for large scale, analytic-styled data warehousing. Infobright enables MySQL users to move up to data warehouses that support data volumes of 1-10TB or more with these key capabilities:

  • Column-oriented design
  • High data compression capabilities
  • Advanced optimizer with "Knowledge Grid"
  • High-speed loader