Storing data in global variables

[Daniel Weiss]

Is it a good practice to load a lot of data in to global variables when the application is started in order for it to be available for constant data entry instead of always using the lookup (the data is always the same stored in a table with a single record only), or would it be a burden to the application,

Thank you,
Daniel Weiss

[Tom Cone Jr]

RE: Storing data in global variables

This is a useful technique, which I regularly use.

However 'a lot of data' might make it unwieldy, depending on what your phrase means. For example, it would not be practical to store the contents of the Encyclopedia Britannica in a series of variables on startup, just so they'd be available instantly later on.

-- tom

[David Mason]

RE: Storing data in global variables

Daniel,

I do store some data in global variables when leaving my startup screens. This is only data that I will constantly use throughout the open session. Variables take up a very small amount of space and are quick, but can get out of hand if tooo many are utilized.

Dave

[Edward F. Schulz]

RE: Storing data in global variables

Hi David,

I have a similar situation in a dues paid application. The user enters
600 to 1000 records for each member every month. There are 6 fields to
be filled for each record, 3 of them are date fields the other 3 are
numeric to enter how the dues is distributed in 3 different accounts.
What I do is in a form just prior to the form where the records are
generated I set the defaults for 4 of the fields, because those 4 are
the same for 95% of the records to be entered. Then uses sys_send_keys
to tab thru the fields that have defaults leaving the user to only
have to make 2 entries in the remaining fields. Hence the user checks
all of the records to be entered on her checkoff sheet and then breezes
thru all of them really quick. After all of the similar records are
entered then the last 5% go much slower but still routine and goes
quickly due to the meager number of records left to be entered. The
form that sets the defaults uses ask vars to set the default value.
A button then takes the user to the dues_entry form to make the entries. A button on the dues_entry form takes her back to the form to change defaults
when needed. This up grade from A4 to A5 has shortened dues entry from
2 days to about 4 hours. It could be easily adaptable to your
application. Another feature on the dues_entry form which is on a set
of members-dues_entry is, configuring F3 so that when dues_entry is
entered it will send the focus directly from the members region to the
first field of the dues_entry where sys_send_keys breezes straight to
a field where manual entry is required. When the last field of the
record is filled, F3 takes her back to the members region and advances
her to the next member. This thing runs as smooth as milk down a babies
throat. Tom Cone was a tremendous help in developing this technique.

Give it some thought,
efs

[JerryBrightbill]

RE: Storing data in global variables

Another useful option when you have a lot of data that is common for many records, is to create a table with the data. In many of my apps, I store company specific information and other "stuff" like default form colors, startup indexes, registration numbers, etc in a table. At startup, some of this data is sent to global variables. Usually this is data that will be used repeatedly thoughout data entry or for multiple forms. Other data that is used less frequently is looked up from the table when needed.

One nice thing about doing it this way is that I can save the global variable values back to the table so they will be the same when I open the app the next time.

I use a lot of global variables in some cases. Rather than define them in forms and tables, I have a script that is run by an autoexec script that loads all of them at startup. If I find I need a new one, I add its definition to the startup script. In this script I also usually set a default value for each. Once the variables are loaded, accessing them is much faster than using a lookup.

Jerry

[Geoffrey Hollander]

RE: Storing data in global variables

Daniel,

Good question; as you can see the debate continues...

I use a lot of global variables (200+), which are loaded from my autoexec script whenever I launch my application. They don't take up that much room, are very fast and, as a result of having these things "at my beck and call", I can bring them into an operation anytime, anywhere...

The most useful criterion I have found for variables is to use the most restricted level possible that still serves your purpose. If it's just used for one thing one time, keep it constrained to the script, and so forth.

It's also true that you can save a lot of things to an "internal" table for subsequent recall. I use that technique as well, but mostly for those things which must stay persistent when the application has been closed and reopened again (e.g. saving the path to the last file opened by the application).

Incidentally, when I want to use memory variables in objects such as a form or report, I like to have them globally defined before I begion to work in design mode. That way I can just use them as I would any other readily available field.

Hope this is useful.

Regards,

Geoff Hollander

[Daniel Weiss]

RE: Storing data in global variables

Thanks All for your responds

Actually what I was referring to; is I have a table where my clients can enter in the data, which is used for 5 e-mailing types (when the order is received, when the order was shipped, etc.). See sample below
The data the client enters is used for the standard text in the body of the Email (header, footer, etc). The table holds about 6000 characters between all the fields, the table has only one record and the client can only make changes to that record they cant enter a new record or delete it.
I have a scheduled script, which run every 20 minutes as follows

Checks for new records or for change of status of the record

Enters a new record in a table that has 4 fields 1) inv # 2) a memo field 3) E-mail address 4) logical filed, the memo filed is the body of the E-mail

The memo filed is gathered using the header data entered in the E-mail setup table and from necessary fields in the invoice header table and the line items from the invoice items table and the rest of the data from the E-mail setup table.

Next, it appends the new records to an Access table (.mdb), which is attached via ODBC to my database
Marks the records as appended so it won�t append it again

Last, it calls an EXE file (sys_shell) written in Visual basic6, which E-mails all new records in the mdb file-using Outlook to the E-mail address on each record. The EXE. File then marks the records in the mdb file as send.

All this is done on the background of the server without interrupting the users.

My question is if should load the data from E-mail table when the application is started or locally each time the script runs. I think in this case it would be better to do locally, or am I wrong?

Below is a sample of an E-mail the system sends after shipping
It is possible the line wont show correctly here but in an E-mail it works real nice


Dear Daniel Weiss,

We would like you to know that we shipped the item(s) you ordered on June 12, 2001, Please allow 12 hours for the tracking information to be available on the shipper's Website.

Order Number: I1005091

Qty Item Price
1 NIKON COOLPIX 880 DIGITAL CAMERA $1,351.00
1 EH-21 AC ADAPTER/CHARGER F/ COOLPIX 880
1 EN-EL1 LITHIUM RECHARGEABLE BATTERY F/CP880
1 COMPACT FLASH USB PORT CARD READER
1 64 MB COMPACT FLASH HIGH SPEED MEMORY CARD
1 CASE- POINT AND SHOOT SMALL

Shipping and Handling $20.00
Total Amount $1,371.00

* If this is a partial shipment, your other items will ship separately, as soon as they're available, and tracking information will be e-mailed to you. Despite the separate shipments, rest assured that your total shipping charges for this order will not exceed the amount we originally promised.

This shipment was sent to:
Alpha Software Inc.
83 Cambridge St.
BURLINGTON, MA 01803
USA

Via UPS
Tracking Number: 1ZA7V4160348839350

Should you have any questions or problems when you receive your order, please contact us at:
www.foreigndesigns.com

Thank you for shopping with us, and we hope to see you again soon.



Thank you again,
Daniel Weiss

[Daniel Weiss]

RE: Storing data in global variables

I see the forum striped all spaces in the line items columns but on the E-mails I checked it put the Quantity in the left column then the Item and in the right column the amount

Daniel

[Daniel Weiss]

RE: Storing data in global variables

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[JerryBrightbill]

RE: Storing data in global variables

Sorry, not quite sure how you are using variables. If you already have the data in a table, why move it to variables?

One thing that is very important to remember in networked apps is the "extent" of the data. Table data is the same for everyone since all normally access the same table on the "server". Global variables are resident in memory and exist on the local computer so their value can be different for each user. Is this what you need to know?

Jerry