Communications of the ACM

sees himself above all as an engineer, retaining a professional engineer’s zest for the elegant solution of difficult problems and faith in the power of careful and rational analysis. As he wrote in a note at the end of the transcript of an oral history interview I conducted with him in 2004, “My work has been my play.” 1

When database specialists look at IDS today they immediately see its limitations compared to modern systems. Its strengths are more difficult to recognize, because its huge influence on the nascent software industry meant that much of what was revolutionary about it in 1963 was soon taken for granted. Without IDS, or Bachman’s tireless championing of the ideas it contained, the very concept of a “database management system” might never have taken root. IDS did more than any other single piece of software to broaden the range of business problems to which computers could usefully be applied and so to usher in today’s “digital” world where every administrative transaction is realized through a flurry of database queries and updates rather than by completing, routing, and filing in triplicate a set of paper forms.

References

1. Bachman, C. W. Oral history interview by Thomas Haigh September 25–26, 2004, Tucson, AZ. ACM Oral History Interviews collection. ACM Digital Library, http://dl.acm.org/citation.cfm?id=1141882.

2. Bachman, C. W. The origin of the integrated data store (IDS): The first direct-access DBMS. IEEE Annals of the History of Computing 31, 4 (Oct.–Dec. 2009), 42–54.

3. Bachman, C. W. The programmer as navigator.

Commun. ACM 16, 11 (Nov. 1973), 653–658.

4. CODASYL Data Base Task Group. CODAS YL Data Base Task Group: October 1969 Report.

5. CODASYL Systems Committee. Survey of Generalized Data Base Management Systems, May 1969.

Association for Computing Machinery, New York, 1969.

6. Haigh, T. Charles W. Bachman: Database software pioneer. IEEE Annals of the History of Computing 33, 4

(Oct.–Dec. 2011), 70–80.

7. Haigh, T. How data got its base: Generalized information storage software in the 1950s and 60s.

IEEE Annals of the History of Computing 31, 4 (Oct.– Dec. 2009), 6–25.

8. Haigh, T. Inventing information systems: The systems men and the computer, 1950–1968. Business History Review 75, 1 (Spring 2001), 15–61.

Thomas Haigh ( thomas.haigh@gmail.com) is a visiting professor at Siegen University, an associate professor of information studies at the University of Wisconsin— Milwaukee, and immediate past chair of the SIGCIS group for historians of computing.

Copyright held by author.

1970s and 1980s, and commercial database management systems based on this approach were among the most successful products of the mushrooming packaged software industry.

Bachman spoke memorably in his 1973 Turing Award lecture of the “Programmer as Navigator,” charting a path through the database from one record to another. 3 The network approach used in IDS required programmers to work with one record at a time. Performing the same operation on multiple records meant retrieving a record, processing and if necessary updating it, and then moving on to the next record of interest to repeat the process. For some tasks this made programs longer and more cumbersome than the equivalent in a relational system, where a task such as deleting all records more than a year old or adding 10% to the sales price of every item could be performed with a single command.

IDS and other network systems encoded what we now think of as the “joins” between different kinds of records as part of the database structure rather than specifying them in each query and rebuilding them when the query is processed (see Figure 2). Bachman introduced a data structure diagramming, often called the “ Bachman diagram” to describe these relationships.c Hardcoding the relationships between record sets made IDS much less flexible than later relational systems, but also much simpler to implement and more efficient for routine operations.

IDS was a useful and practical tool for business use from the mid-1960s, while relational systems were not commercially significant until the early 1980s. Relational systems did not become feasible until computers were orders of magnitude more powerful than they had been in 1963 and some extremely challenging implementation issues had been overcome by pioneers such as IBM’s System R group and Berkeley’s INGRES team. Even after relational systems were commer- c C.W. Bachman, “Data Structure Diagrams,”

Data Base 1, 2 (Summer 1969), 4–10 was very
influential in spreading the idea of data struc-
ture diagrams, but internal GE documents
make clear he was using a similar technique
as early as 1962.
cialized the two approaches were seen
for some time as complementary, with
network systems used for high-perfor-
mance transaction-processing systems
handling routine operations on large
numbers of records (for example, credit
card transaction processing or custom-
er billing) and relational systems best
suited for “decision support” analytical
data crunching. IDMS, the successor to
IDS, underpins some very large main-
frame applications and is still being
supported and enhanced by its current
owner Computer Associates, most re-
cently with release 18. 5 in 2014. Howev-
er it, and other database management
systems based on Bachman’s network
data model, have long since been su-
perseded for new applications and for
mainstream computing needs.

Although by any standard a successful innovator, Bachman does not fit neatly into the “hackers, geniuses, and geeks” framework favored by Walter Isaacson. During his long career Bachman had also founded a public company, played a leading role in formulating the OSI seven-layer model for data communications, and pioneered online transaction processing. In 2014, he visited the White House to receive from President Obama a National Medal of Technology and Innovation in recognition of his “ fundamental inventions in database management, transaction processing, and software engineering.”d Bachman