12 Jan
2012
12 Jan
'12
9:22 p.m.
On 2012 Jan 12, at 7:30 AM, Gene Buckle wrote:
On Wed, 11 Jan 2012, Brent Hilpert wrote:
I liked working on the Microdata-Reality/Pick system at the time,
albeit as someone quite young and inexperienced. Working and
programming with the database seemed quite effective for the nature
of the work (business/accounting).
The wikipedia article on the Pick system mentions files being
structured with items, attributes, values and sub-values, which would
fit with:
value = EXTRACT( item, attribute, value, sub-value )
so as you surmised it looks like EXTRACT and <> are equivalent.
On 2012 Jan 11, at 7:04 PM, Gene Buckle wrote:
It's manipulating a dynamic array - x<attribute, value, sub-
value>. This is how Pick (and Pick-alikes like REALITY, UniVerse,
etc) store data.
If you have a record that looks like this:
001: NAME
002: ADDRESS
003: CITY]STATE]ZIP
You could work with it like this:
read workrec from customer.file, "1001" then
cust.name = workrec<1>
cust.addr = workrec<2>
cust.city = workrec<3,1>
cust.st = workrec<3,2>
cust.zip = workrec<3,3>
end
Pick has its quirks like any other DB system, but it stomps the
guts out of SQL on pure flexibility alone. On Wed, 11 Jan 2012, Brent Hilpert wrote:
Well, I couldn't really say .. 1978 was about the last time I used
the Microdata/Pick system.
IIRC, EXTRACT() was used to access the fields in a record, the
record perhaps having been READ() from the database; I don't
recall the exact semantics. Would it make sense if it were
something like:
value = EXTRACT( record, index1, index2, index3 )
I never saw the x<a,b,c> notation .. syntactic shorthand
introduced later?
The BASIC on the Microdata-REALITY system had
many of these
improvements back in the mid-70's, on a professional/business/
mini-computer platform: structured if-then-else, statement
numbers are optional, indentable, etc. Below is a code snippet
from a program I wrote in 1977/8 (the numbers on the far left
are line numbers, not part of the source).
Known as Pick BASIC or DataBASIC.
70 IF
EXTRACT(FA,2,LC(NP),LC(P)+1)=1 THEN M=M+1;
DA=INSERT(DA,M,0,0EXTRACT(FA,NP,LC(2),1))
I've not seen this notation used
(well recently) is the EXTRACT
above equivalent to: IF FA<2,LC(NP),LC(P)+1> THEN.... ?