I have to say this first -- just because ERwin calls it "physical" that doesn't mean anything. ERwin uses "physical" model to mean "product-specific logical" model. They use "logical" to mean "product-independent logical" model.

ERwin doesn't do physical modeling. Not even a little bit. The physical layer of a relational database …

Time is simple. You can make it complicated with any one of a large number of dumb-as-dirt decisions.

In the Real World™, time may be a quantum field (read stuff by 't Hooft ). For that matter, space itself may have some quantum granularity. Or, this could be a handy hack …

There aren't too many variations on the open-ended date range problem. We have a table of events or rules or policies that have start dates. Some have end dates, because they've been replaced or superseded. Others don't have end-dates because they apply for the foreseeable future.

There are two kinds …

Background: I'm looking at parsing certain X12N messages. There's a Perl program on CPAN to do X12 parsing ; the program itself isn't useful, but the X12 messages are defined via INI files. There's also a Python X12 parser with the X12 messages defined via XML files. I don't really like …

I hate to complain, but there's a Python syntax rule that has slightly cramped my style. The problem stems from a need to describe a really complex and extensible structure.

We need to describe X12N messages, which have a rather complex structure, and the structure can be customized. While the …

See Sean McGrath's Spot the warning signs in configuration file design for thoughts on the ever-gnarly problem of how to provide a workable set of configuration parameters to a program.

A programming language has all the advantages as a language for encoding parameters. I see why it's rare -- too many …

See Spolsky's Talks at Yale, Part 1 of 3 for a fairly typical summary of formal methods in software development. Here's the part RL liked: "Now, if the spec does define everything about how the program is going to behave, then, lo and behold, it contains all the information necessary …

In Lenses That Distort Our Software , I noted that the relational model of data can distort our view of the underlying reality that software models. In that posting I was whining about how meaningful structure is sacrificed to force fit information into the rows and columns of the relational world …

A taxonomy of pipeline alternatives is a big, hairy deal, involving lots of alternatives. While your basic API methods are relatively few in number, each language and platform introduces new options. Without some focus, it's challenging to produce a big, fluffy description of all potential alternatives.

However, the interesting thing …

First, the confusion. A couple of comments asked for code, offering to "fix" the problems. Specifically, offering to optimize or improve the PL/SQL. The code was already posted, but I failed to make that clear. Here's a recap of the various blog entries on this subject.

1. PL/SQL vs …