----- Original Message -----
Sent: Tuesday, July 08, 2008 3:28
PM
Subject: RE: [amibroker] More on Database
Structure and Local Storage
Hello
Tomasz:
Of
course you are right, again, but the page in help/guide is still incomplete in
order to impart a good understanding of how this all
works.
How
does one use local database (say with FastTrack data) and still get nightly
updates installed so everything works right?
What
does local database really mean as everyone has to get their data from some
external source?
I
clicked on the DATA SOURCE (vs my previously just checking the Enable local
storage button), and everything seemed the same. I could go between
symbols in the tree, and things seemed to plot the same. There was no
long disk activity suggesting that AB was writing data from the FT data files
to the local AB data files. So how does that work?
My
critical question: Am I able to use FastTrack data, locally, and
write custom values to OI that will be saved, AND STILL, somehow, update
nightly FastTrack data? Can you say it is possible, and if so how are
nightly updates accomplished?
This
is all critical to a custom application (as we have been discussing in other
messages).
Thanks
for continuing to provide support on this issue.
Ken
Hello,
To switch to LOCAL database, you just go to
File->Database Settings and change "Data SOURCE" to
"(local database)".
But that means that you are NOT using FastTrack as data
source.
You can *not* have both,
i.e. using FastTrack as a data source and having database
WRITE ability, because
access to FastTrack database is READ ONLY.
The only exceptions are COMPOSITES (and any symbol marked as
"use local database only"
in the Information window) - they are NOT present in
external database and
are always saved locally.
It was explained in the docs I pointed
previously:
Best
regards,
Tomasz Janeczko
amibroker.com
----- Original Message -----
Sent: Tuesday, July 08, 2008 1:46
PM
Subject: [amibroker] More on Database
Structure and Local Storage
Can someone explain to
me how I make the FastTrack database a local one?
Background: I have had
a FT db for years, with local storage disabled? I want to write to the
OI field and preserve the written data. I checked "Enable Local Storage" but
nothing different happened.
Next, I tried to scan
all symbols with a simple formula (I remembered having to do that years ago
with a TC2000 database that came on a CD--I thought the same kind of step
was needed.). Amibroker got hung on a single symbol and I had to
End Program. AB would lock if I even clicked on this same
symbol.
Next, I created a new
FastTrack database with a different name and copied over the appropriate
files to the new DB folder. I enabled Local Storage from the start.
All looked good. Except that writes to the OI field in the new DB
would not save. I tried the scan all symbols trick again, and again it
hung on the same symbol, certainly suggesting my FastTrack data itself is
corrupt on that one symbol. (Special updates with the FastTrack data
designed to correct problems did not seem to change
anything.)
My question is how do I
get the FastTrack database to be local and to allow writes to the OI field
to stick?
My second question (as
I assume I have to have the data in the Amibroker folders and not just in
the FastTrack folders for the AB DB to be local), is how do I update the
nightly downloads of new data which FastTrack will stick in their own
file/folder?
Thomasz, can you
help?
Thanks,
Ken