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#SQL

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SQL is a standard language for storing, manipulating and retrieving data in relational databases.

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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Contestant

If you already know Java (or .Net) and perhaps also have used other document databases (or looking for one), but you are new to the InterSystems world, this post should help you.

InterSystems IRIS Cloud Document is a fully managed document database that lets you store JSON documents and query them with familiar SQL syntax, delivered as a cloud service managed by InterSystems.

In this article pair I’ll walk you through:

  • Part I - Intro and Quick Tour (this article)
    • What is it?
    • Spinning up an InterSystems IRIS Cloud Document deployment
    • Taking a quick tour of the service via the service UI
  • Part II - Sample (Dockerized) Java App (the next article)
    • Grabbing the connection details and TLS certificate
    • Reviewing a simple Java sample that creates a collection, inserts documents, and queries them
    • Setting up and running the Java (Dockerized) end‑to‑end sample

The goal is to give you a smooth “first run” experience.

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Contestant

This is the second part of an article pair where I walk you through:

  • Part I - Intro and Quick Tour (the previous article)
    • What is it?
    • Spinning up an InterSystems IRIS Cloud Document deployment
    • Taking a quick tour of the service via the service UI
  • Part II - Sample (Dockerized) Java App (this article)
    • Grabbing the connection details and TLS certificate
    • Reviewing a simple Java sample that creates a collection, inserts documents, and queries them
    • Setting up and running the Java (Dockerized) end‑to‑end sample

As mentioned the goal is to give you a smooth “first run” experience.

Open Exchange app
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Contestant

We were testing upgrades on our internal systems recently, and were initially surprised to see a change in some instances of SQL behavior. On further investigation, the changes make a lot of sense, and are easy to adapt to. But, to hopefully save you some time and provide additional information in case this is something you too find curious or interesting, we thought we would share our understanding of the changes and how we got around it to preserve previous behavior where desired.

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Contestant

In InterSystems IRIS, when you compile a persistent class, you automatically get a SQL table. Sometimes, there are situations that require having a slightly (or not so slightly) different names/options in SQL compared to Object model. Here are some of the settings that you can change to make it happen.

Class-level settings

They define the "Face" of your class when it appears as a table in the SQL catalog.

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