“Version 4.4 of the Lord Discography has 13,000 new leader and group recording sessions added, mainly from the first part of the alphabet. Armstrong, Basie and Ellington have all been up-dated so that the new disc, replacing as it does more than 26 books, includes 26,856 leaders, 149,350 recording sessions, 833,520 musician entries and 832,791 tune entries. (No, I didn’t count them, but with the computer it would have been easy to).

The upgrade works much more swiftly and efficiently (although I could find little fault with the early disc). 4.4 lets one copy and paste session details into records away from the discography. This is invaluable if one wants to include them in an e-mail to a friend or indeed in any Word document. It is now possible to print out up to 50 recording sessions at a time. I rarely found the need to consult the copious ‘Help’ section but individual pages from it can now be print out for permanent reference.

The new disc has been re-programmed to provide a virtually endless variety of advanced searches. These can even be made by individual word rather than a specific name and can find a record label, matrix number or just a general date. Also included are leader, musician and tune indexes which provide useful summaries of each category.

All the details can be found at the web site www.lordisco.com. The free demonstration there includes a tour of the discography. It’s quick and easy to download. Incidentally CD-ROM Version 3.3 is still available there at a reduced price until sold out”.

In 1917, the Original Dixieland Jass Band made the first jazz record. The five-man band had just come to New York and stirred something of a midtown meltdown with its guilty pleasures. “Disaster is coming to hundreds of young girls,” one guardian of public morals warned. Fortunately, public morality was no concern of Columbia Records, which promptly recorded the band and kick-started the history of recorded jazz.

As landmark firsts go, the ODJB may not rank with Gutenberg or even Lindbergh. Still, here we are 90 years later with a large legacy on our hands. If someone were to assemble a list of every jazz record, it would cover about 22,000 printed pages.

Which brings us to Tom Lord, a jazz researcher in Vancouver, British Columbia, who has done just that. Mr. Lord became hooked on the music at age 12 when he saw Louis Armstrong in “The Glenn Miller Story.” But it was his success as a mechanical engineer and president of an international container company that permitted him to pursue his private passion for records. He is now most noted as the compiler of “The Jazz Discography,” a huge work that he began in the 1980s and that eventually grew to 34 600-page volumes at a retail cost of about $2,200.

But such reference works have a way of becoming obsolete the moment they’re published. So Mr. Lord did it differently. He built his information empire on a database, not a manuscript. It was a leap of innovation that has allowed him to move beyond books and produce “The Jazz Discography” as a single CD-ROM version 7.0 (available at www.Lordisco.com) whose extraordinary search options can navigate millions of names, numbers and songs with a few keystrokes. The result is a treasure trove full of surprises that will fascinate any student of American music eager to know the most recorded songs, the most recorded musicians, and the nature of jazz itself.

A discography is a mix of bookkeeping and excavation. After the ODJB made its splash, jazz dipped underground and sped through the next 20 years with an amiable disregard for its own accumulating history. It wasn’t until Benny Goodman became a sensation in the ’30s that jazz acquired a curiosity about its fabled past. In 1936 Charles Delauney became jazz’s first Boswell when his 271-page discography, “Hot Discographie,” was published in France. It would be the Rosetta Stone for all record research to follow, listing master numbers, labels, dates, personnel and catalog numbers for hundreds of jazz sessions. Over the next 40 years the science of discography grew and evolved.

Mr. Lord picked up the baton in the early ’80s, using his computer skills to develop an index for the jazz magazine Cadence. “I did it in a computerized spread sheet called Lotus 1-2-3, a DOS-based program that cross-referenced interviews, record and book reviews. In 1983, personal computers were pretty new things. But after developing that database, I began to think there could be an application in the discography field. I figured it would take me about three or four months to do the database. Well, it ended up taking me three years. A discography looks very simple in print, but there’s a lot behind it in terms of programming. Also there’s the sheer task of sitting down at a keyboard and typing decades of detail into a database. At times it’s just an overwhelming task.”

Mr. Lord hired several assistants who hammered away at the endless procession of names and numbers. When enough data piled up to fill 600 pages, Mr. Lord explains, a new volume would appear. Eleven years and 26 volumes later, he finally made it through the Z’s in 2001. Another eight books of indexes and addendums followed, bringing the total work to 34 volumes in 2004.

But by then publishing had changed, and in early 2002 “The Jazz Discography” appeared as a CD-ROM for the first time. It was programmed to search leaders, musicians and songs and went up to the year 2001. Since then, each year 10,000 fresh entries have been added in annual revisions. The latest version, 7.0, has expanded search options that include dates, words and phrases. Search the phrase “wall street,” for example, and you’ll find one tune called — no kidding! — “The Provincial Correspondent to the Wall Street Journal.”

There is only one record of that song, by Dick Goodwin in 2003. But Mr. Lord’s database shows 1,675 versions of “Body and Soul,” making it the most recorded melody in jazz history. New Zealand disc jockey John Joyce used Mr. Lord’s latest CD-ROM to break out a list of songs logging more than 500 recordings. He found 70 in all, 12 of which surpassed 1,000 versions. Following “Body and Soul” are “St. Louis Blues” (1,628), “Summertime” (1,358), “Sweet Georgia Brown” (1,302), “Take the A Train” (1,201) and “Round Midnight” (1,184).

Such lists are fascinating because they impose a sense of order on the chaos of factoids. Of those 70 songs, for example, 11 are by Duke Ellington, six by George Gershwin, and three by Cole Porter. One third were written by working jazz musicians; the rest by songwriters. The most recent is Erroll Garner’s “Misty,” with 582 recordings since 1954. But the late critic Whitney Balliett didn’t call jazz “the sound of surprise” for nothing. Mr. Lord’s complete song index shows 52 versions of “Hey Jude,” 29 each of “Blowin’ in the Wind” and “Mrs. Robinson,” plus slumming tours of “Satisfaction” (10), “Purple Rain” (three), and even “Thriller” (two).

Almost as surprising is what the data say about musicians. Of the 12 most recorded jazzmen, for instance, four are bassists, including Milt Hinton, who tops the entire list at 1,174 sessions. Ellington is a close second. Of the 50 most recorded jazzmen in history, I count only nine still living, suggesting the scarcity of recording opportunities in recent decades. Among those not among the most prolific 50 are Miles Davis, John Coltrane, Dizzy Gillespie, Charlie Parker and Oscar Peterson.

Not in the index at all are Washington attorney Leonard Garment and former Fed Chairman Alan Greenspan. An understandable omission, perhaps. Yet each played bebop saxophone in the Henry Jerome orchestra of 1944 and can be heard on an obscure Jerome CD called “A Taste of Crazy Rhythm,” according to Mr. Garment’s 1997 autobiography. This is the kind of oversight now easily corrected.

Beyond such gee-whiz trivia, though, a discography, by its choices, defines its domain. “That’s a whole other thing,” says Mr. Lord. “What is jazz? I don’t know that I want to get into that. It would be impossible with the number of recordings I’m handling to listen to every one, even if they were available. Frankly, in the end it’s an arbitrary call. But we try to include any recordings that have jazz content or performers in them.”

So blues singers Bessie Smith and Ma Rainey, who recorded with many jazz musicians, are in, while a rural bluesman like Robert Johnson, who didn’t, is out. Tony Bennett, Frank Sinatra and Bing Crosby are covered selectively, as is Rosemary Clooney. There are surprises here too. Jackie Gleason, who fellow-traveled with jazzmen on his mood-music albums, claims 23 sessions. Lawrence Welk gets six and Kenny G is listed as a sideman on two early dates. Even Frank Zappa’s “Jazz From Hell” is included. Nora Jones’s “Come Away With Me” is also in, but with the notation “limited jazz content.”

So jazz geeks may quibble about this inclusion or that omission. But Mr. Lord has cast a wide net, knowing that revisions will be easy and that in the 90 years since the first jazz record the definition of jazz has become a moving and often controversial target. Now with its legacy securely digitized, the music has a basic reference work that can move as fast as the music.

In the October 2002 and March 2004 issues of Jazz Journal, Steve Voce wrote enthusiastically about the CD-ROM versions of Tom Lord’s Jazz Discography which he described as “incredible, imaginative and brilliant” and “one of the (two) most indispensable devices you can use to enhance your collection.” I fully agree with Steve’s comments which can be read in full at www.lordisco.com/reviews. He covered versions 3.3 and 4.4 and these have been revised and updated each year, the latest being CD-ROM 12.0, available to new subscribers at $350, with 50% discounts on updates.

However, in October 2007 Lord introduced the first online subscription service which has all the same facilities as the CD-ROM version giving immediate access to musicians, tunes, sessions and record companies but it is updated virtually every day. With word search, and dates as well it’s possible to track down almost everything within seconds. As to the contents, the statistics alone make the strongest point. Tom Lord’s 26 printed volumes listed 136,263 recording sessions which had increased to 149,350 on version 4.4 of the CD-ROM but, as of March 2012, the online version has 203,868. Apart from this massive increase in information the online version also enables one to check new issues and reissues added to the database each day, going back 31 days. Another facility, only available online, is one I’ve found particularly useful. For the first time you can now catalogue your own collection. It’s a straightforward process: after tracing individual records and discs by catalogue number or via the musicians’ lists, etc., a couple of clicks highlight that entry in green, identifying it as yours. You can then search either just your own collection or the full database, for as long as you subscribe. I should also say that initially this identified more omissions than I’d expected but perhaps that was naive on my part as no discography, especially on this scale, can ever be totally complete, and the myriad CD reissues available worldwide must be a discographer’s nightmare.

On his home page, Lord admits that jazz discography is a work in progress and ensuring accuracy and completeness is an endless task. Questions raised about missing Mosaics, Savoys and the many European issues in my collection have resulted in fairly speedy amendments and additions, but you do need to provide details of your source and any opinions need to be backed up with some authority, which I find reassuring. Another issue, only really made obvious by computerization, is variation in tune titles.

You’ll find 853 versions of On Green Dolphin Street, for example, but another 24 of just Green Dolphin Street. Similarly, Star Dust (1288) and Stardust (66) or Lady Be Good (1021) and Oh, Lady Be Good (17). Although presumably reflecting how these appeared on the respective issues, a cross reference would be useful.

A couple of final things which have cropped up during my subscription: Lord doesn’t include DVDs, videos or any filmography (unless they’re on record, of course). “I’ve got more than my hands full with discography,” he told me. But he does now include music available on some download sites with the recent 300+ issues on Wolfgang’s Vaults catching my eye.

I’ve been subscribing now for nearly 12 months and cannot imagine being without it. Even with the qualifications mentioned above it is surely the most comprehensive jazz discography presently available and the speed and ease with which one can trace the information make it invaluable, largely displacing printed versions.

A one-year subscription is $150 with the special offer above for new subscribers ($9.99/month). It works on Windows, Mac and UNIX. An introductory video and much fuller details are all available on the website.

Ever wonder how many times Louis Armstrong recorded his hit number “Struttin’ With Some Barbecue”? The answer is more than 50, from the original performance in 1927 with the Hot Five to a 1967 date with his All-Stars.

Or if that reaches too far into the past, how about something more associated with pop music — like whether there are any jazz versions of Paul Simon’s “Bridge Over Troubled Water.” The answer is: yes, indeed. From Charlie Byrd and Paul Desmond to Lionel Hampton, Nancy Wilson and Michel Legrand and beyond.

Or how about unlikely musical collaborations? Herbie Hancock and David Sanborn? Yep, a 1975 date with Jaco Pastorius and a pair of 1978 dates with Flora Purim.

And did you ever wonder whether Freddie Green, the ineffable presence in the Count Basie rhythm section, ever recorded with anyone other than Basie? He sure did. Dozens of times, from Teddy Wilson and Billie Holiday to Diane Schuur to Caterina Valente.

How, you may ask, do I have this information so readily at hand? I found it all, with little more than a few strokes on my computer keyboard, in a remarkable CD-ROM titled “The Jazz Discography.” Written and produced by a dedicated jazz scholar named Tom Lord, it compiles his 26 published volumes of jazz discography into a single, incredibly useful computer database.

Arts that function primarily in the popular arena have never done a particularly thorough job of chronicling their histories. A tendency to focus on the latest star arrival, to list the current levels of sales, to emphasize annual award giving, has for the most part taken precedence over the sort of detailed, long-range views that are common to the classical worlds of music, art, dance, etc.

Jazz lies somewhere in between. True, there is a plethora of books examining one era or another, and several encyclopedic tomes, including the Feather-Gitler “Biographical Encyclopedia of Jazz,” the “All Music Guide to Jazz,” the “Penguin Guide to Jazz on CD” and “The Rough Guide to Jazz.” All serve useful purposes in their specific areas.

But there’s nothing like “The Jazz Discography.” Containing the equivalent of 31,700 printed pages of information, it includes data on more than 410,000 jazz releases on 78- and 45-rpm discs, LPs and CDs. (As a point of comparison, the current edition of the “All Music Guide to Jazz” includes reviews of around 20,000 recordings.)

Does all this sound too esoteric, too redolent of baseball brainiacs who can instantly quote the batting average, home runs and runs batted in of any player one cares to name? Well, sure, that aspect exists. But what Lord has done by placing all this information into a cross-referenced database that allows easy access to information from a variety of directions is create an extraordinarily valuable historical tool. And one can easily imagine its applicability in other musical genres.

What makes “Discography” even more fascinating from the layman jazz-fan perspective is the opportunity to explore from a personal point of view. Is New Orleans music your choice? You can track every recording ever made by Kid Ory, King Oliver, Sidney Bechet or Jelly Roll Morton.

Prefer swing? You can follow the complete recorded history of a player such as Bunny Berigan (from the bands of Fred Rich, Hal Kemp, Tommy Dorsey, Freddy Martin, Glenn Miller, Benny Goodman and his own orchestras).

Along the way, you’ll come across Berigan dates with Louis Armstrong and Billie Holiday. And each listing includes complete personnel and original recording information.

If bebop and beyond are your preferences, there are similarly intriguing paths to take, from Charlie Parker and Dizzy Gillespie’s 1945 recording with singer Slim Gaillard (which produced the unforgettable “Flat Foot Floogie”) to the long line of players who streamed through Miles Davis’ final sessions.

For those who concentrate on songs, there’s the option to search for every number recorded by a jazz artist, complete with leader name, sidemen and dates. And a multiple search menu locates every instance in which as many as three individual players recorded together.

Maintaining such an enormous amount of data is an ongoing task. The current version of “The Jazz Discography” is identified as 3.3 and is short on information beyond the late ’90s. The next update, 4.4, will add new entries.

At first glance, the price looks high: $277 in the U.S., with purchasers eligible for future upgrades at 50% off published prices. But keep in mind that the “All Music Guide to Jazz,” with its 20,000 listed recordings, is priced at $32.95, and it’s only a book. In that comparison, “The Jazz Discography,” with its 410,000 releases and its array of search options, suddenly seems like a bargain.

“The Jazz Discography” is available from Lord Music Reference Inc., 5975 Matsqui Street, Chilliwack, BC, Canada V2R 0G6 Info: (604) 846-6608. On the Web at www.lordisco.com.