Unable to retrieve my data from a View in Database into Appian RT/ ER

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

David Jimenez — Tue, 30 Apr 2024 15:56:56 GMT

How long does the query takes to execute and what's the size of the datasubset received? YOu can check it directly in the database......

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

Chris — Tue, 30 Apr 2024 15:51:22 GMT

One thing I always like to rule out when a DS is published successfully, but cannot access data, is that this is not an Oracle database with the view residing in a different schema than the home schema of the user account. In this case, we need to create a synonym to the view, in the home schema of the database account. This may not be the case, but for a while there has been a discrepancy with Oracle DBs and the different Java libraries that Appian uses for database validation, vs connection at runtime (Teneo vs Hibernate). One can access objects in a different schema and one cannot.

However the memory and timeout error do not tend to this situation, typically we would see "table does not exist" or something of the sort. Just to note.

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

Harsh Kumar Agarwal — Tue, 30 Apr 2024 15:44:46 GMT

Can you share the CDT and XSD details of view? Specifically, primary key information.

It appears to me a silly mistake around primary key configuration.

I am ruling out the threshold or memory issue as QE not retrieving a single row with primary key only.

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

MaryamLNU — Tue, 30 Apr 2024 15:28:58 GMT

Yes, it is working fine. The only problem is in only when I am retrieving. Even though the Data Store is not showing any error.

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

Harsh Kumar Agarwal — Tue, 30 Apr 2024 15:26:52 GMT

is your view loading fine at database side?

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

MaryamLNU — Tue, 30 Apr 2024 15:25:25 GMT

Sure Harsh Kumar Agarwal ,

Output of the above code:

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

Harsh Kumar Agarwal — Tue, 30 Apr 2024 12:24:09 GMT

Can you share the output of following code:

a!queryEntity(
  entity: cons!Test_DSE_VW_MULT_TARGET,
  query: a!query(
    selection: a!querySelection(columns: { a!queryColumn(field: "vwid") }),
    pagingInfo: a!pagingInfo(startIndex: 1, batchSize: 1)
  ),
  fetchTotalCount: false()
)

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

MaryamLNU — Tue, 30 Apr 2024 12:16:10 GMT

Thanks Stefan Helzle , let me work on the two things you mentioned.

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

Stefan Helzle — Tue, 30 Apr 2024 12:08:24 GMT

In the first line, it just repeats the error message you already have.

My first guess is a timeout issue. And you can only solve that by speeding up that database view.

My second guess is a memory issue. The query returns too many rows with too many fields. Paging ist the solution.

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

MaryamLNU — Tue, 30 Apr 2024 12:07:03 GMT

Sure Harsh Kumar Agarwal ,

Up on selecting the constant of the Entity, I am getting this error in Query Editor:

Yes I created a Unique identifier column for my view which we are using as a PK.

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

MaryamLNU — Tue, 30 Apr 2024 12:03:18 GMT

Thanks Stefan Helzle , I am attaching a stdout log file. Kindly help me to identify what is wrong. I am unable to find.community.appian.com/.../TOMCAT-Log.txt

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

Harsh Kumar Agarwal — Tue, 30 Apr 2024 11:52:02 GMT

Can you share the code of QE?

Also, did you check that your view has a column with unique identifier which you are using as a primary key?

RE: Unable to retrieve my data from a View in Database into Appian RT/ ER

Stefan Helzle — Tue, 30 Apr 2024 09:12:28 GMT

Do you see any details in the tomcat stdout log file? For me, this looks like a timeout issue. DB views are known for this kind of issues.