| Title: | FOCUS, from INFORMATION BUILDERS |
| Moderator: | ZAYIUS::BROUILLETTE |
| Created: | Thu Feb 19 1987 |
| Last Modified: | Mon May 05 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 615 |
| Total number of notes: | 1779 |
We're in an evaluation, and are having trouble resolving a couple
of issues...
Q1: Has anyone had any luck with multiple joins? We are using
FOCUS 5.0 VX1.3.1, and have been unable to do more than two
files (one join) at a time (Documentation says up to 16).
Q2: Has anyone tried to use FIDEL (CRTFORM) on a terminal that
is set up for half duplex (local echo)? We've tried a number
of things, but are unable to cause FIDEL to inhibit echo
(except, of course the .N. attribute, but that doesn't apply
to T. fields...)
Thanks in advance for any responses...
-- Brian
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 18.1 | More info please | STOPIT::LINNELL | Mon Dec 07 1987 04:46 | 9 | |
Please supply an example of our join command.
Syntax =
JOIN field1 in file1 to {ALL} field2 IN file2 {AS join-name}
{} = optional
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| 18.2 | A Join failure example | DPDMAI::BEATTIE | But, Is BLISS ignorance? | Mon Dec 07 1987 11:02 | 20 |
Re: .1 (and sorry for the omission)
as I understand it, the problem is that, given three files A, B,
and C, with a field AB common to A and B, and a field BC common
to files B and C:
JOIN AB in B to AB in A as JOIN_1
JOIN BC in C to BC in B as JOIN_2
Each of these joins "works" in that no error is generated, but when
we attempt to table file C to print fields from C, and corresponding
fields from A (which should be joined via B?), we get errors (the
fields in A are "unrecognised words").
Please note that A,B, and C are RMS files. Their concurrent use
in a live FORTRAN application precludes conversion to multi-segment
FOCUS DB file (*sigh*).
- Brian Beattie
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| 18.3 | Ready to be confused? | STOPIT::LINNELL | Tue Dec 08 1987 05:40 | 64 | |
When you perform a join on multi (ie more than 2) files, you must
build them as if you were putting together one large file from building
blocks. When you make the first join, it is advisable to start with
the file that you wish to TABLE later. After that join all the fields
from the second file in the join are now considered to be in the
first file when it is referenced. So to join another file in to
the list you must refer to the first file again.
A bit confusing so let me use your example.
You wish to table file C, so lets start there.
JOIN BC IN C TO ALL BC IN B AS JOIN_1
That will join all records in B that have a matching key in C to
C. ie.
---------
| C |
---------
|
/|\
---------
| B |
---------
FOCUS now considers that all the fields in B are now in file C and
can be refered to by Tabling C. So to add in file A you must join
it to file C. ie.
JOIN AB IN C TO ALL AB IN A AS JOIN_2
This now connects all records in A that have a matching record in
C to C (B)
_________
| C |
---------
|
/|\
_________
| B |
_________
|
/|\
_________
| A |
---------
Now Table file C and you will get all fields from A B C in you report.
An easy way to check you joins is to do a
CHECK FILE C PICTURE
command from the Focus prompt, after you have done the join, this
will draw a structure diag for the top file with all relations hanging
off it.
This works for RMS files and focus files.
Any problems with this explanation give me a ring on 7830-4972,
but remember I am in the UK so get the timing right!
All the best
Adam Linnell
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| 18.4 | thanks for multi-join help! | DPDMAI::BEATTIE | But, Is BLISS ignorance? | Wed Dec 09 1987 10:47 | 7 |
RE: .3
Thanks very much. Your explanation was clear,made sense, and
worked beautifully. I wonder why the IBI tech that pops up here from
time to time wasn't able to tell us that?
-- Brian
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