[Top] [All Lists]

Re: [ontolog-forum] Language vs Logic

To: "[ontolog-forum]" <ontolog-forum@xxxxxxxxxxxxxxxx>
From: Pavithra <pavithra_kenjige@xxxxxxxxx>
Date: Tue, 14 Sep 2010 18:49:59 -0700 (PDT)
Message-id: <584711.56735.qm@xxxxxxxxxxxxxxxxxxxxxxxxxxx>

Even if you are talking about AsIs Data base,   Ed Yourdon is the person started Structure Analysis concept later he wrote books about Object Oriented Analysis and Design with Peter Coad   ( I have signed copy of the book .)  I remember attending Peter Coad's lecture when he released the book in 1991.

People who studied these topics, follow the some analysis and design techniques all their lives.

This is the most interesting topic I read in a long time..    Thanks Dr. Sowa,

--- On Tue, 9/14/10, Rich Cooper <rich@xxxxxxxxxxxxxxxxxxxxxx> wrote:

From: Rich Cooper <rich@xxxxxxxxxxxxxxxxxxxxxx>
Subject: Re: [ontolog-forum] Language vs Logic
To: "'[ontolog-forum] '" <ontolog-forum@xxxxxxxxxxxxxxxx>
Date: Tuesday, September 14, 2010, 9:32 PM

John, Jim, Ed, Dave and et al,


I think this thread is going in the wrong direction entirely.  It seems to me that the effort should be focused on the English statements found in the AsIs database, and the ways in which AsIs users made errors in the database.  


In a recent case, I was able to show that over 40% of the rows in an actual database had errors of one kind or another in them – and not just the English statement fields, even the so called structured fields are like that.  


To show that, I had to write a program to extract the actual data in the database, not just the data fields which happen to be compliant with the meta data specifications.  Often, the entered data is "cleaned" by the software to meet the specs, but it often isn't the same semantics that the user entered, and is often clearly semantically different than what user intended.  Users just don’t much care how much sweat the managers, BAs, SysEs and SWEs have expended on their behalf.  They just use it to get their jobs done with a minimum of attention.  Remember that collecting data is not their major concern – they want the sales to go through no matter what they have to do to get there.  


Reengineering a database (not the code, but the data and data model) is itself a discovery process that has the usual four lower level processes running concurrently.  These are <Experimenting, Classifying, Observing, Theorizing>, as shown in the following chart of the sixteen way interactions among the four processes:  



Where each box in the figure begins with a number, that number correlates to a paragraph or longer description of the interaction for those two processes in the document at www.englishlogickernel.com/Patent-7-209-923-B1.PDF The approach described there uses corpus analysis and context modeling to discover the semantics used in the actual database.  Knowing that the information was perceived in a particular way by each front end user helps the development architects figure out how to design the ToBe system, and without it, that information is normally not available to the ToBe system designers.  





Rich Cooper


Rich AT EnglishLogicKernel DOT com

9 4 9 \ 5 2 5 - 5 7 1 2


-----Original Message-----
From: ontolog-forum-bounces@xxxxxxxxxxxxxxxx [mailto:ontolog-forum-bounces@xxxxxxxxxxxxxxxx] On Behalf Of John F. Sowa
Sent: Tuesday, September 14, 2010 5:50 PM
To: ontolog-forum@xxxxxxxxxxxxxxxx
Cc: Ken Orr; Arun Majumdar
Subject: Re: [ontolog-forum] Language vs Logic


Jim, Ed, Dave, and Rich,


I completely agree with what you say below  But I will add that

proper tools can make *many orders of magnitude* improvement --

e.g., going from 80 person years of tedious work to 15 person weeks

of more exciting stuff.


I realize that you're not going to believe what I say below, but you

can verify it by asking Ed Yourdon.  He did the initial consulting

before recommending Arun Majumdar and Andre Leclerc for a short

study project, which ended up in delivering exactly what a major

consulting firm claimed would take 80 person-years by the hand

methods that you describe.


Another person who is familiar with the project and all parties

involved is Ken Orr (on cc list above).


JR>> This is OK as long as you realize that data integrity and data

semantics are

>> contained in the applications, that you understand these legacy systems well

>> enough to be sure you understand the data semantics and that you can

>> reproduce them without error. Legacy databases are often full of codes that

>> are meaningless except when interpreted by the applications.


EB> Strongly agree.  Reverse engineering a "legacy" (read: existing/useful)

> database can be an intensely manual process.  Analysis of the

> application code can tell you what a data element is used for and how it

> is used/interpreted.  The database schema itself can only give you a

> name, a key set, and a datatype.  OK, SQL2 allows you to add a lot of

> rules about data element relationships, and presumably the ones that are

> actually written in the schema have some conceptual basis.


I also agree.  But it is possible to analyze the executable code and

compare it to *all* the English (or other NL) documentation -- that

includes specifications, requirements documents, manuals, emails,

rough notes, and transcriptions of oral remarks by users, managers,

programmers, etc.


For a brief summary of the requirements by the customer, the method

by which Arun and Andre conducted the "study", and the results,

stored on one CD-ROM, which were exactly what the customer wanted,

see slides 91 to 98 of the following:




Just type "91" into the Adobe counter at the bottom of the screen

to go straight to those slides.


EB> Reverse engineering a database is the process of converting a data

> structure model back into the concept model that it implements.  And the

> problem is that the "forward engineering" mapping is not one to one from

> modeling_language_  to implementation_language_.  It is many-to-one,

> which means that a simple inversion rule is wrong much of the time, and

> the total effect of the simple rules on an interesting database schema

> is always to produce nonsense.  Application analysis has the advantage

> of context in each element interpretation; database schema analysis is

> exceedingly limited in that regard.


That is part of the job, but it doesn't solve the problem of 40 years

of legacy code with numerous patches and outdated documentation.

The customer's problem was (1) to *verify* the mapping between

documentation and implementation and report all discrepancies

(or at least as many a could be found), (2) to build a glossary of

all the English terminology with cross references to all the changes

over the years, (3) to build a data dictionary with a specification

that corresponded to the implementation, not to the obsolete

documentation, and (4) to cross reference all the English terms

with all the programming and database terms and all the changes

over the years.


EB> That said, other contextual knowledge can be brought to bear.  If, for

> example, you know that the database design followed some "information

> analysis method" and the database schema was then "generated"...


Good luck when some of the programs predated any kind of "methods",

other documentation was lost years ago, and the people who wrote

or patched the code retired, died, moved on, or just forgot.


EB> So, if you know the design method and believe it was used consistently

> and faithfully, you can code a reverse mapping that is complex but

> fairly reliable, but you still have to have human engineers looking over

> every detail and repairing the weird things....


Arun and Andre were the two engineers who checked anything that the

computer couldn't resolve automatically.  And the computer did indeed

discover a lot of weird stuff.  Look at slides 95 to 97 for a tiny

sample of weird.


But as they continued with the analysis, Arun and Andre found that

the computer's estimate of how certain it was about any conclusion

was usually right.  They raised the threshold, so that the computer

wouldn't ring a bell to alert them unless it was really uncertain

about some point.


DMcD> Most of the legacy systems we see were forward engineered once upon

> a time, but then modified in place, without going through the original

> model to design to code process.  So you have a mix of things that can

> be faithfully reverse engineered mixed in with things that just got bolted on.


Yes.  And when the code is up to 40 years old, there are a lot of

ad hoc bolts.  That's why the big consulting firm estimated that it

would require 80 person-years to do the job.  But Arun and Andre

did it in 15 person-weeks (while the computer worked 24/7).


RC> Personally, I have found that most AsIs DBs are useful histories

> of how people reacted to the expressed interfaces.  The code, which

> is supposed to interpret the fields, is often not consistent with

> the way people used the database.


That's true.  That's why you need to relate the implementation

to *all* the documentation by users of every kind as well as

by managers and programmers of every kind.  They all have

different views of the system, and it's essential to correlate

all their documents and cross reference them to each other and

to the actual implementation.


EB> Yes, you can be stuck with maintenance programmers and ignorant

> users.  But that means you are genuinely flying blind with respect

> to the actual data content and intent...


Yes, that's why the customer asked the consulting firm to analyze

all their software and all their documentation.  When that estimate

was too high, they asked Ed Yourdon for a second opinion, and he

called in Arun and Andre.   They delivered a solution that gave

the customer everything that the big firm claimed that they would

require 80 person-years to do.


Please read the slides.  And as I said, you don't have to take

my word for it.  There is also a Cutter Consortium technical

report written by Andre and Arun.  Ask Arun for a copy.  But

it doesn't say as much about the NLP technology as I wrote

on the iss.pdf slides.






Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/ 

Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/ 

Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx

Shared Files: http://ontolog.cim3.net/file/

Community Wiki: http://ontolog.cim3.net/wiki/

To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J

To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx


-----Inline Attachment Follows-----

Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/  
Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/  
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/ 
To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J
To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx    (01)

<Prev in Thread] Current Thread [Next in Thread>