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The relational database model has prevailed for decades, but a new type of database — known as NoSQL — is gaining attention in the enterprise. Here’s an overview of its pros and cons.

For a quarter of a century, the relational database (RDBMS) has been the dominant model for database management. But, today, non-relational, “cloud,” or “NoSQL” databases are gaining mindshare as an alternative model for database management. In this article, we’ll look at the 10 key aspects of these non-relational NoSQL databases: the top five advantages and the top five challenges.

Note: This article is also available as a PDF download.

Five advantages of NoSQL

1: Elastic scaling

For years, database administrators have relied on scale up — buying bigger servers as database load increases — rather than scale out — distributing the database across multiple hosts as load increases. However, as transaction rates and availability requirements increase, and as databases move into the cloud or onto virtualized environments, the economic advantages of scaling out on commodity hardware become irresistible.

RDBMS might not scale out easily on commodity clusters, but the new breed of NoSQL databases are designed to expand transparently to take advantage of new nodes, and they’re usually designed with low-cost commodity hardware in mind.

2: Big data

Just as transaction rates have grown out of recognition over the last decade, the volumes of data that are being stored also have increased massively. O’Reilly has cleverly called this the “industrial revolution of data.” RDBMS capacity has been growing to match these increases, but as with transaction rates, the constraints of data volumes that can be practically managed by a single RDBMS are becoming intolerable for some enterprises. Today, the volumes of “big data” that can be handled by NoSQL systems, such as Hadoop, outstrip what can be handled by the biggest RDBMS.

3: Goodbye DBAs (see you later?)

Despite the many manageability improvements claimed by RDBMS vendors over the years, high-end RDBMS systems can be maintained only with the assistance of expensive, highly trained DBAs. DBAs are intimately involved in the design, installation, and ongoing tuning of high-end RDBMS systems.

NoSQL databases are generally designed from the ground up to require less management:  automatic repair, data distribution, and simpler data models lead to lower administration and tuning requirements — in theory. In practice, it’s likely that rumors of the DBA’s death have been slightly exaggerated. Someone will always be accountable for the performance and availability of any mission-critical data store.

4: Economics

NoSQL databases typically use clusters of cheap commodity servers to manage the exploding data and transaction volumes, while RDBMS tends to rely on expensive proprietary servers and storage systems. The result is that the cost per gigabyte or transaction/second for NoSQL can be many times less than the cost for RDBMS, allowing you to store and process more data at a much lower price point.

5: Flexible data models

Change management is a big headache for large production RDBMS. Even minor changes to the data model of an RDBMS have to be carefully managed and may necessitate downtime or reduced service levels.

NoSQL databases have far more relaxed — or even nonexistent — data model restrictions. NoSQL Key Value stores and document databases allow the application to store virtually any structure it wants in a data element. Even the more rigidly defined BigTable-based NoSQL databases (Cassandra, HBase) typically allow new columns to be created without too much fuss.

The result is that application changes and database schema changes do not have to be managed as one complicated change unit. In theory, this will allow applications to iterate faster, though,clearly, there can be undesirable side effects if the application fails to manage data integrity.

Five challenges of NoSQL

The promise of the NoSQL database has generated a lot of enthusiasm, but there are many obstacles to overcome before they can appeal to mainstream enterprises. Here are a few of the top challenges.

1: Maturity

RDBMS systems have been around for a long time. NoSQL advocates will argue that their advancing age is a sign of their obsolescence, but for most CIOs, the maturity of the RDBMS is reassuring. For the most part, RDBMS systems are stable and richly functional. In comparison, most NoSQL alternatives are in pre-production versions with many key features yet to be implemented.

Living on the technological leading edge is an exciting prospect for many developers, but enterprises should approach it with extreme caution.

2: Support

Enterprises want the reassurance that if a key system fails, they will be able to get timely and competent support. All RDBMS vendors go to great lengths to provide a high level of enterprise support.

In contrast, most NoSQL systems are open source projects, and although there are usually one or more firms offering support for each NoSQL database, these companies often are small start-ups without the global reach, support resources, or credibility of an Oracle, Microsoft, or IBM.

3: Analytics and business intelligence

NoSQL databases have evolved to meet the scaling demands of modern Web 2.0 applications. Consequently, most of their feature set is oriented toward the demands of these applications. However, data in an application has value to the business that goes beyond the insert-read-update-delete cycle of a typical Web application. Businesses mine information in corporate databases to improve their efficiency and competitiveness, and business intelligence (BI) is a key IT issue for all medium to large companies.

NoSQL databases offer few facilities for ad-hoc query and analysis. Even a simple query requires significant programming expertise, and commonly used BI tools do not provide connectivity to NoSQL.

Some relief is provided by the emergence of solutions such as HIVE or PIG, which can provide easier access to data held in Hadoop clusters and perhaps eventually, other NoSQL databases. Quest Software has developed a product — Toad for Cloud Databases — that can provide ad-hoc query capabilities to a variety of NoSQL databases.

4: Administration

The design goals for NoSQL may be to provide a zero-admin solution, but the current reality falls well short of that goal. NoSQL today requires a lot of skill to install and a lot of effort to maintain.

5: Expertise

There are literally millions of developers throughout the world, and in every business segment, who are familiar with RDBMS concepts and programming. In contrast, almost every NoSQL developer is in a learning mode. This situation will address naturally over time, but for now, it’s far easier to find experienced RDBMS programmers or administrators than a NoSQL expert.

Conclusion

NoSQL databases are becoming an increasingly important part of the database landscape, and when used appropriately, can offer real benefits. However, enterprises should proceed with caution with full awareness of the legitimate limitations and issues that are associated with these databases.

About the author

Guy Harrison is the director of research and development at Quest Software. A recognized database expert with more than 20 years of experience in application and database administration, performance tuning, and software development, Guy is the author of several books and many articles on database technologies and a regular speaker at technical conferences.

By Guy Harrison

Choosing the wrong ISP can be disastrous. To ensure that you make the right choice, you need to consider a number of factors — from uptime to capacity to equipment to field response.

Internet service providers (ISPs) have become critical IT infrastructure partners. As cloud computing, email, and Internet connectivity have grown in importance, so too have the circuits that connect organizations to the Internet. When selecting an ISP, don’t base your choice only on price or familiarity. Consider these 10 factors when seeking an ISP.

Note: This article is also available as a PDF download.

1: Uptime commitments

Of all the promises ISPs make, none is worth anything if the ISP doesn’t fulfill its uptime commitments. The circuits simply have to work. If they don’t, organizations become dependent upon redundant or backup service. Look for service level agreements that provide real and measurable targets for uptime, not just 99.9% operational guarantees. Insist on specific wording that governs what happens when service fails. Does your organization receive credit off its bill? Will the ISP scramble a technician 24×7? Both? Ensure these details are in writing.

2: Downstream speed

Many, including most customers, tend to rate an ISP solely on advertised downstream speeds. While many ISPs promote 20Mbps or faster service to businesses, these claims need to be tested. Too often, IT pros hear “2Mbps is the best service we can get in that building” or “Circuits in that part of the city aren’t as fast as other locations.” Marketing claims are occasionally excessive; excuses are plentiful. Test all new circuits’ downstream speeds the day they’re installed, a month later, and quarterly after that.

Better yet, before ordering, inquire what other clients, using the same service, are experiencing nearby. That’ll give you a better barometer as to how potent an ISP’s downstream speeds actually are.

3: Upstream capacity

As with downstream speeds, upstream speed claims must be tested, too. The increasing popularity of VPNs, remote access, and automated offsite backups place great premiums on an ISP’s upstream capacities. As organizations need to push more and more data to mobile users in the field, upstream bandwidth capacity will only grow in importance.

4: Port freedom

Don’t assume that once a telecommunications circuit is in place, an organization is ready to get to work. Many ISPs, in an effort to optimize network performance, selectively block ports. I’ve been unable to use Telnet and other ports, depending upon the ISP’s policies. Worse, the policies aren’t always uniform across an entire ISP’s network. ISP A may block Telnet on networks on the east side of town, but not the west. ISP B, meanwhile, may not block Telnet at all.

5: SMTP flexibility

Many ISPs, and I see this with former Ma Bell companies in particular, block SMTP port 25 traffic to any mail servers but their own. Obviously, the goal is to reduce the distribution of unsolicited email, but the solution places an undue burden on customers. Typically, the ISP recommends setting its servers as the outbound SMTP servers within email clients or switching to alternative ports, but that poses trouble for users who also travel with laptops or who are less technical. Be sure to check with the ISP to learn whether it supports open SMTP port 25 traffic.

6: Accessible technical support

When things go wrong, and they will go wrong, how accessible is technical support? I’ve called for assistance recovering a downed business circuit only to hear a recorded message stating support hours are between 9am and 5pm Monday through Friday. That’s unacceptable for an ISP. Be sure the ISP you select provides technical support that meets your organization’s requirements. If you close up shop everyday at 5pm, this won’t be an issue. But if you run critical third shifts 24×7×365, better support is a necessity.

7: Responsive field service

If a failure occurs (the most common issue I see is failed modems due to lightning strikes, but I’ve also repeatedly seen wiring go bad in the ISP-supported network interface device, or NID), how quickly does the ISP commit to resolving the outage? In many cases, ISPs think nothing of mailing a replacement modem or rolling a truck a full business day later. That could mean the organization is dead in the water, unable to process credit cards, send or receive e-mail, access the Internet, or process orders for days. Be sure you know the ISP’s field response policies, and be sure they match your organization’s requirements, before signing a contract.

8: Equipment quality

IT professionals know which modems fail and how often. They also know which modems with built-in firewalls should really be set to bridge mode and mated to better business-class routers. Not wanting to disparage any manufacturers, I’ll just say that when my office has an opportunity to work with Westell or Motorola modems, we feel better. ISPs often don’t provide a choice of modem; they just deploy the model they support. When comparing two ISPs’ bids, consider the quality of each firm’s equipment. The less time an IT pro must spend on site administering, reconfiguring, or restarting network equipment, the better.

9: Equipment flexibility

Some ISPs enable customers to supply their own modems. Take advantage of these opportunities, as supplying your own network equipment not only allows you to select the quality you want but potentially lowers costs, too. Occasionally, ISPs lease modems to customers. I believe it makes more sense to purchase network equipment, where possible, to achieve lower total costs of ownership.

10: Pricing

Price is the last factor that should be considered when selecting an ISP. Uptime, capacity, service accessibility, and field response are much more critical, especially considering the importance of Internet circuits to businesses today. But price matters, too. When all else is equal — from uptime to performance, support, and equipment — price becomes the differentiating factor. When factoring price, however, be sure to compare apples to apples. Some ISPs require customers to purchase a modem or CSU/DSU, while others lease this equipment. And some ISPs require multi-year contracts. Such lease and long-term arrangements may end up costing more in the long run, so compare costs carefully.

Other considerations?

Have you had good (or bad) luck with your organization’s ISP? What other factors would you add to this list?

By Erik Eckel

Social networking sites provide unprecedented opportunities to get the word out about yourself and your business. Unfortunately, many people don’t have a clue how to use these tools effectively. Deb Shinder offers 10 practical suggestions.

Social networking tools, such as Facebook, Twitter, Windows Live, and Google Buzz, are great for keeping in touch with friends and family and having fun. Once banned from the business world, they are now being allowed or even embraced on many company networks. Some employees use social networking as a quick break from work. Studies have shown that taking short breaks can make workers more productive, and hopping over to your Facebook page for five minutes to check friends’ activities can be a quick and efficient way to “get away” mentally, even if you need to stay physically in place.

Other people are going further and using social networks to build business relationships with colleagues and potential clients. LinkedIn is specifically targeted to that audience. And some are taking it further still and using social networking sites to actively promote themselves and their businesses. This can be particularly effective for self-employed people, such as consultants, writers, and trainers. Many more would like to utilize these tools to increase their business presence but aren’t sure how to go about it. In this article, we’ll look at ways — beyond the obvious — to enhance your reputation (and your company’s) through social networking. After all, it’s long been recognized that word of mouth is one of the best forms of advertising, and social networking is just an online extension of that.

Note: This article is also available as a PDF download.

1: Just showing up is not enough

There’s a saying that “Just showing up is half the battle.” But it’s important to remember that it’s only half. Too many people get stuck at that point. They show up; they set up accounts on a dozen or more social networks — but then they let them languish and never post. People check those sites, see no new content, and after a while give up. Having a “dead” page is worse than having no page at all.

The primary reason people let their social networking sites die is lack of time. Be sure you have the time to devote before you set up a business-oriented site, and have a posting plan (for example, a reminder to yourself to post something every other day). Stick to the plan! Many people get overwhelmed because they take on too many social networks at once. If your time is limited, choose just a few (for example, Facebook, LinkedIn, and Twitter).

2: Just because you build it, that doesn’t mean they’ll come

Even if you faithfully update your social networking pages every day and blast out clever and useful tweets from morning ’til night, it doesn’t matter much unless you have followers and friends to see those promotional masterpieces. Before you can use your social networking sites to promote yourself and your business, you need to promote those social networking sites themselves.

Privacy is a big issue when you’re sharing personal information on social sites, but for business, the more open your site is, the better. To get maximum exposure, configure your privacy settings to let everyone see what you post, not just the people who are already your followers or friends. But before you do that, be sure to read the next item in this list.

3: Separate your business and personal online lives

If you’re serious about promoting your business self, you need to set up a separate social networking “place” for business-related posts. I have separate Twitter accounts for different purposes and one Facebook account for friends and family with another one for my readers and business colleagues. Another alternative is to use one social network (such as Facebook) for socializing and another (such as LinkedIn) for all your business networking.

The key here is that you want to present yourself as a professional when promoting your business, and it’s hard to do that if your old college buddies are posting things on your wall about all the hard partying you did when you were in school.

4: Use aggregator apps to better manage your social networks

One way to manage your social networking accounts is to visit each site on a daily or other regularly scheduled basis. An easier way is to use tools such as TweetDeck that let you see and manage multiple SN accounts all at once, without going to the Web sites and logging in each time. It’s a great time aver and lets you see all your updates “at a glance” in different columns, as shown in Figure A. When you’re doing it all from one app, it’s much easier to remember to post to all of your social networks on schedule.

Figure A

Aggregator apps let you manage multiple social networks at once.

5: Don’t flood the market

Posting regularly is important, but it’s just as important not to over-post. If you use an aggregator app that makes posting easy, you might be especially tempted to fire it up in the morning and send out five or 10 posts all at once on all your networks. It’s much better to space them out throughout the day, so that your followers and friends don’t get overwhelmed or lose interest in what you have to say after seeing several posts in a row from you. Facebook, for example, will hide some of the posts in your friends’ feed if there are many in a row from the same person, so they might not even see them all if they don’t explicitly click the link to see more.

A nice feature in TweetDeck (the PC version, not the more limited iPhone/iPad version) is that you can enter a post and then schedule it to be posted later, as shown in Figure B.

Figure B

Some clients, such as TweetDeck, allow you to schedule updates to be posted later.

6: It’s not all about you

Maybe you think that since you’re promoting yourself (or your business), all you need to do is post about what you’re doing. I see people who put out post after post about themselves but never seem to participate in the discussions or otherwise indicate that they’re also reading their friends’ posts.

Social networking is designed to be interactive — it’s most effective when you don’t just use it as a broadcast medium for one-to-many messages, but also truly interact with your contacts. That means letting them know that you’re reading their posts, whether by posting comments, hitting the Like link, retweeting their relevant posts, or sending direct messages. This is the way you really connect — and it’s those two-way connections that are most likely to benefit your career or business.

7: Strike a balance

The content of your posts counts. While you shouldn’t get too personal, you shouldn’t be too business-like, either. That is, your contacts don’t want to just see post after post about the product or service you provide, until it seems that it’s just spam. They’ll unfollow or “hide” you pretty quickly if that happens.

Let your business associates get to know you a little — the professional you, that is. Post occasionally about your activities that are relevant to your business. For instance, you can post the funny story about what happened to you on the plane on the way to a business conference. Or you can post about the great book you just read about your area of expertise. Even though these don’t directly promote your business, they provide a glimpse of you as a person, without getting overly personal. People like to do business with people they know.

8: Don’t just link

Some people use their social networking sites to post links — lots and lots of links. When those links are relevant to your business, that’s great, but it’s not enough. Think of how you feel when you go to a Web site that’s nothing but links to other Web sites. Do you see that site as a real resource or just as a way station for getting to the real resources?

Use the link as a way to highlight your own expertise and opinions and to (subtly) help promote yourself. If you find a great article about a topic in your field of interest/work, instead of just tweeting the URL, post the URL in your blog along with a one- or two-paragraph summary of your thoughts about the article. What parts are best? Are there statements made with which you disagree? Can you give a real-world example of some concept the article discusses? Then your tweets and FB posts can point to your blog post instead of the original article, which gets you more hits on your blog and more important, makes the readers think of you more as a collaborator/content provider/expert commentator rather than just someone who posted a URL.

9: Dress it up with multimedia

Sometimes, words just aren’t enough — and often they don’t stick in a person’s mind nearly as long, nor as positively, as visual images do. Today’s social networking services make it easy to dress up your posts with more than just text, and those features aren’t just for sharing pictures of your pets and your family vacation.

Are you a consultant, posting about a recent high-profile project? Add a few photos taken onsite (with the permission of the client, of course — who’s likely to be happy to get the free advertising). If a picture is worth a thousand words, what’s a video worth? Want to promote your reputation as a freelance software developer? How about a video tutorial showing what your latest app can do?

10: Use paid advertising wisely

Many of the social networking sites, such as Facebook, support themselves by taking paid advertising. You can buy an ad; the advantage of this is that it will appear on the pages of people you don’t know. It’s a way to introduce yourself and your business to strangers without sending them friend requests (which many will ignore and consider rude coming from people they don’t know). The key here is to make the ad interesting and intriguing enough to draw them to your own site. Otherwise, it will be ignored, as most online advertising is.

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By Debra Littlejohn Shinder