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Why do these clauses affect SQL performance?

select ID from some_table where row_status in ('I','U') order by ID limit 5 - makes the query infinite
select top 10 ID from some_table where row_status in ('I','U') order by ID - the same
select ID from some_table where row_status in ('I','U') order by ID - is fast

Actually there are no rows in the table having row_status 'I' or 'U'.

I asked Gemini and it recommended me rewrite the query as

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I have a Postgres table which should be migrated to IRIS. The table has a computed column, like:

CREATE TABLE example_table (
    id VARCHAR(10) PRIMARY KEY,
    normalized_id VARCHAR(10) GENERATED ALWAYS AS (LPAD(id, 10, '0')) STORED
);

IRIS also has the LPAD function but I can't figure out how to achieve the same result using pure SQL DDL.

Tried this:

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Question
· Dec 21, 2025
XDBC memory leaks

I have a business service that actively reads data from a remote Postgres database. OnProcessInput opens a XDBC (actually JDBC) connection, executes an SQL query, fetches several thousand rows, iterates the resultset, and closes the connection. On each iteration I also need to update each source row in the remote database using PreparedStatement.

In other words, in every OnProcessInput call I have a long running SELECT statement and several thousands small UPDATE statements.

The problems I'm facing are:

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I am experimenting with OpenTelemetry and recently connected all IRIS instances to telemetry servers.
I'm not interested in emitting custom metrics since IRIS does it fine, regarding tracing - we can use %Trace classes to emit custom traces, but what about logging?

I see that IRIS is able to send system log messages to the OpenTelemetry servers:

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Question
· Aug 8, 2025
count() is too slow. Why?

I have a table with 5M rows, the table contains lab observation codes and display names, both columns have type varchar(2000) and both are indexed.

The query looks like:

select code_1_text, count(code_1_text)
  from demo.observation_lab
  group by code_1_text
  order by 2 desc

The table contains ~1000 distinct display names.

It takes 4 minutes for the query to complete on a VM with some pretty old Xeon, 4 cores, 32G RAM, NVME SSD and Linux on board.

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I'd like to ask you for recommendations on how to properly use repository dependencies when using VSCode and Client-side editing.
Suppose I have projects A, B and C, with A being independent, B depending on A, and C depending on A and B.
I am currently working with the main project C, and I want to be able to contribute to all the other projects in a single VSCode window (instead of opening three instances). How do you solve this problem? Git submodules? ZPM? Something else?

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I have two instances of IRIS, one is Production and another one is Staging (both managed by Docker) and I want to set up a full daily recover of the Staging server from a full backup of the Production server. I know how to do this manually using the DBREST utility, as well as how to make a copy of the database by making a full copy of the durable directory (however this option requires a full stop of the Production-database). What is the best way to automatically restore all databases from a full backup using scripting?

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My IRIS instance is connected to a Postgres database using SQL Gateway and linked tables.
One of these tables is projected to the Patient class. I want to select a record from this table by ID and convert it to a FHIR resource using the %ExistsId and %OpenId methods.
I noticed that if I call these two methods from the console, the record is always found.

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I am developing locally on my IRIS instance using VSCode and client-side editing approach. How can I automatically export a single .cls file/a whole package to a remote TEST/PREPROD server using a script or command line and recompile the unit remotely? Are there any more simple and straightforward ways than CI/CD explained in the series of articles by Eduard?

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I'm trying to call a SOAP web service which is implemented in .NET Classic and requires NTLM authentication. The client class was generated by %SOAP.WSDL.Reader. The problem is that neither NTLM authentication works nor can I handle the exception since VSCode debugger says that all meaningful fields and properties are empty (the same request works fine in Postman):

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