As Published In
Oracle Magazine
November/December 2007

COMMENT: In The Field

A Place for Everything

By Ari Kaplan

Oracle's free ILM Assistant helps enterprises implement cost savings.

Finding the storage necessary for corporate data is a continuous problem. An Independent Oracle Users Group (IOUG) survey indicates that 92 percent of respondents anticipate that their database storage needs will increase in 2007, and 64 percent say they'll increase spending on storage to meet those needs.

In part, storage needs have increased because companies need to retain data for long periods to satisfy compliance requirements such as Sarbanes-Oxley and HIPAA. In addition, many companies routinely preserve e-mail and other data as a defense against possible lawsuits. While hanging on to all that data could save the day in such a situation, storing it in the meantime is problematic and expensive.

Enter a Solution

Many companies are finding the solution to this dilemma in the practice of information lifecycle management (ILM). I applied ILM principles to a large insurance company client, which had more than 300 applications, about 200 Oracle databases, and nearly 100 data centers—and major compliance issues, as you might guess. Using ILM approaches, the insurance company retained the data it needed to satisfy legal requirements, while significantly reducing the overall cost of storage.

The basic idea of ILM is to manage data actively throughout its lifecycle. In particular, you want to choose the most appropriate storage solution for your data at each point in its lifecycle. For example, you might want to keep a recent e-mail (or transaction) readily accessible for, say, 30 days so that you can use it. After that, you might want it somewhat accessible for another 60 days, just in case. Beyond that, you probably don't want it clogging up your system, although you might be unwilling to throw it away.

The solution to this situation is to design several tiers of storage. Tier A might consist of fast and roomy hard drives, which are expensive. Tier B might be hard drives that are slower and smaller but inexpensive. Tier C might be bulk storage, such as a tape drive library or, increasingly, low-cost Serial Advanced Technology Attachment (SATA) disks.

Once you establish these tiers of storage options, you assign data to each one. Must-have data goes on tier A, nice-to-have data moves to tier B, and don't-care data gets dumped onto tier C. You set up a mechanism—automatic is the goal, but possibly manual—to maintain this arrangement, moving aging data from one tier to another and defining and enforcing compliance policies. For its lifetime, then, the data will migrate between the data tiers, and access to it will be controlled. Eventually the data may be archived, or it can remain inside the database forever.

The potential cost savings of this strategy is amazing. Typically, tier A hard drives cost 5 to 10 times more (per GB) than tier B hard drives and up to 50 to 100 times more than bulk tier C storage. In one study, a company moved nearly all of its data from US$72/GB hard drives to a US$4/GB online archive, reducing its storage costs by 94 percent.

This practice does not discard necessary data. If a file is needed to meet compliance requirements or to satisfy discovery in a lawsuit, you can still access it. So ILM saves money while also supporting your company's compliance strategies.

ILM becomes more complicated with databases. You must ensure that applications can find data, no matter where it is physically located. In addition, you don't want to degrade database performance. Several Oracle Database characteristics facilitate an ILM solution: it's fine-grained, has enforceable compliance policies, has application transparency, and is low-cost. 

Next Steps

 READ more about ILM


 JOIN the ILM Assistant forum

Oracle offers a tool to help with the complexity. Oracle ILM Assistant is GUI-based software that can create lifecycle definitions; advise you on when to move or delete data, based on those definitions; display the storage requirements—and cost savings—for a given ILM plan; suggest how to partition a table based on your lifecycle definitions; provide underlying technology such as triggers; and simulate events on a table as if it were partitioned. Oracle ILM Assistant itself does not make any physical changes to your database. But it does generate scripts so that you can perform the necessary tasks when you're ready. And it's free.

ILM is a practice that's gaining acceptance in the marketplace because of its proven cost savings. Using Oracle ILM Assistant can make it easier to finally have the right place for everything. 

Ari Kaplan ( is president of the Independent Oracle Users Group (IOUG) and a senior consultant at Datalink. He founded Expand Beyond Corporation, a leader in mobile IT software. He has been involved in Oracle technology since 1992.

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