Active vs Passive in Reporting Data

[omagarc]

I have found a significant latency when running reports againtst a set that has multiple sql based tables.

The backends are SQL 2k5, Advantage Database Server 8.0, PostGres SQL 8.3

I put my stuff on the sql 2k5 back end as the other two are for disparate practice management and electronic medical record systems.

I found that when running reports I had to change from an active link to a passive link to recoupe speed at the Advantage ODBC connection. Once changed to passive it responded within a reasonable amount of time.

I don't know why this behavior exists on this back end with a live active link connect as queries are pretty fast with passive link updates. When viewing data with the same set in an active link setting, the screen refreshes are as advertised and its only when reporting the same data in an 'active link mode' that it becomes a snails pace

[Steve Workings]

Re: Active vs Passive in Reporting Data

You should run your report directly against the SQL datasource if at all possible. Is there any reason you can't do this?

[omagarc]

Re: Active vs Passive in Reporting Data

The data I need on the report is from three different back-ends thus forcing me to create a set to relate the data. Only one table/back-end appears to be giving me issues and I'm thinking about having a mirror data-set on one of the other two backends to eliminate the problem back-end. It works fine when that table/back-end connection is in passive mode.

I'm testing how I can use web-components in reports as this will essentially solve my problem by using only one back-end/my app to query the other back-ends at report rendering. I'm printing a receipt that my app tracks and query one backend for demographics and the other for future appointments.


.. a little hopium with the web components in reports nice blue bar appears

[Peter.Wayne]

Re: Active vs Passive in Reporting Data

It's very easy to create passive tables for reporting. Just use the a5_refreshPassiveLink() to refresh the passive link and the reports will run virtually instantly. There really is no need to use an active link table with reports. I noticed also when I had an active link table in one of my report sets that all 47000 records were being sent across the network, even though only 1 was needed in the report! Switching to passive link resolved the issue.

[omagarc]

Re: Active vs Passive in Reporting Data

In my case I had to take a different approach because of the likelihood of a refresh statement running at the same time by multiple users plus the added latency should a refresh be required frequently.

Instead I copy the table upon running the app to a temporary folder and then insert a record as the user is working with the live active link tables using the web components. As a user changes or inserts a record, I have a function that will query the active link table and insert it into my temporary table. I may end up doing this for the remaining tables but the performance is acceptable right now and is significantly better than the active link connections I was using

When the user logs off the app, the temporary tables are deleted.

[Peter.Wayne]

Re: Active vs Passive in Reporting Data

Each user gets his or her own copy of a passive link table; they are not shared (to the best of my knowledge). You are doing more work than is necessary, I believe.

[omagarc]

Re: Active vs Passive in Reporting Data

open an active link table with any form/browse then try to refresh the active link table from another computer.

in my experience, refreshing requires exclusive use of the table....

the genies make the coding relatively easy in terms of querying the sql back end and because its just one result, the enter_begin() to my table works like a charm for the five columns that i need and I don't have the added latency of the other 40k+ records to get to it.

[Peter.Wayne]

Re: Active vs Passive in Reporting Data

Omar,
You missed my point -- I said passive link tables, not active link tables. E.g.:

 dim args as sql::arguments
 args.clear()
 args.set("account",account)
 a5_refreshPassiveLinkTable("ps_patient",.f.,.f.,args)
 report.print("New Appt Letter")

were "New Appt Letter" is a report that refers to the "ps_patient" passive link table. Each user has his or her own copy of "ps_patient" and the datasource definition for the passive link table is a simple SQL SELECT statement:

SELECT LAST_NAME, FIRST_NAME, MIDDLE_INI, TITLE, SSN, ADDRESS_1, ADDRESS_2, DOB, SEX, STATE, CITY, ZIP, HOME_PHONE, WORK_PHONE, MOBILE_PHONE, ACCOUNT, MARITAL, suffix FROM patient  WHERE account = :account

Is this clear? If I needed more records in the passive link table I could change the SELECT statement or create a new passive link table.
It is not possible to add records to a passive link table, of course. But if you are interested in running a report that only does SELECT queries then a passive link table is very fast. It's essentially the same technology Alpha Five uses when creating a report using a SQL datasource.
- Peter

[Al Buchholz]

Re: Active vs Passive in Reporting Data

Each user gets his or her own copy of a passive link table; they are not shared (to the best of my knowledge). You are doing more work than is necessary, I believe.

I don't think that happens by default, by perhaps with an alias pointing to the user's My Documents??? or their own shadow? rather than then db_path...

[omagarc]

Re: Active vs Passive in Reporting Data

open an active link table with any form/browse then try to refresh the active link table from another computer.

in my experience, refreshing requires exclusive use of the table....

the genies make the coding relatively easy in terms of querying the sql back end and because its just one result, the enter_begin() to my table works like a charm for the five columns that i need and I don't have the added latency of the other 40k+ records to get to it.

my bad I meant passive link; I've been migrating from dbf to sql and getting different behavior with the different back-ends and its driving me crazy. I know its not a5 but rather the driver between a5 and the data. I'm having a fair amount of success with sql 2k5 and postgres. Advantage ODBC 8.0 driver is driving me nuts and that connection is a source of demographics. Good news is there is always a work around with a5 ...so many ways to do things with data.

So I used the ado import genie to setup the connection/creation of the passive link table and saved the xbasic generated to a script. I modified the script to create the table on the local computer folder to avoid any issues with other users and pointed any data sets to this location. Good to go.

[omagarc]

Re: Active vs Passive in Reporting Data

I created a web component on the passive link that refreshes the data upon initialization of the component. The a5_refreshPassiveLinkTable() wasn't available to me in the web component so I created a function to pass a table name to do the same and it works like a charm.

So I took your code to:

Function refreshme as C (tabname as c)
dim args as sql::arguements
args.clear()
a5_refreshPassiveLinkTable(tabname,.f.,.f.)
END Function

I put refreshme("mytable") in the OnGridInitialize Event on my lookup grid

[omagarc]

Re: Active vs Passive in Reporting Data

I created a web component on the passive link that refreshes the data upon initialization of the component. The a5_refreshPassiveLinkTable() wasn't available to me in the web component so I created a function to pass a table name to do the same and it works like a charm.

So I took your code to:

Function refreshme as C (tabname as c)
dim args as sql::arguements
args.clear()
a5_refreshPassiveLinkTable(tabname,.f.,.f.)
END Function

I put refreshme("mytable") in the OnGridInitialize Event on my lookup grid

I apologize...this addresses a lookup issue and I'm going to sleep.