#SQL

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

All time

Suppose you have an application that allows users to write posts and comment on them. (Wait... that sounds familiar...)

For a given user, you want to be able to list all of the published posts with which that user has interacted - that is, either authored or commented on. How do you make this as fast as possible?

Here's what our %Persistent class definitions might look like as a starting point (storage definitions are important, but omitted for brevity):

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Hi -

I'm trying to rewind a cursor back to the first row after looping part of the way through the implied result set, but I'm not finding a way to make this happen, is there some such iterator variable or directive that I can leverage to accomplish this?

I could code around it by pulling identifiers and/or values into a local array, and then hand code up an iterator over my local results copy, but this feels like a "redesigning of a wheel" approach, and I thought I would check before I start down this path.

Thanks

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Hi Community!

Please welcome a new video on InterSystems Developers YouTube Channel:

Getting Sharded with InterSystems IRIS

https://www.youtube.com/embed/cEz_rJpsku0
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Article
· Mar 2, 2023 3m read
Quick sample database tutorial

Introduction

This is a simple tutorial on the quickest way I found to create a sample database for any purposes such as testing, making samples for tutorials, etc.

Creating a namespace

  1. Open the terminal
  2. Write the command "D $SYSTEM.SQL.Shell()"
  3. Write "CREATE DATABASE " and the name you want for your namespace.

Now you have a new namespace in a faster way than creating it from the Management Portal - which of course offers way more configuration options.

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Article
· Feb 2, 2016 1m read
Creating an IDKEY with a chosen name

What do you do if you want to have the ID field have a meaningful name for your application?

Sometimes it comes to pass that when you're making a new table that you want to have the unique row identifier (a.k.a. IDKEY) to be a field that has a name that is meaningful for your data. Moreover, sometimes you want to set this value directly. Caché fully supports this functionality and it works Suppose you have a class Test.Kyle. The data will be stored like so:

^Test.Kyle(IDKEY)=$LB("",Field1,Field2,...,Fieldn)

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Hello,

searching messages in our Message Bank is quite slow, often runs into timeout.

I wanted to perform a tune table on Ens_Enterprise_MsgBank.MessageHeader because this apparently has not been done yet - the Tune Table utility shows no entries for selectivity, etc.

I tried

 w $SYSTEM.SQL.Stats.Table.GatherTableStats("""Ens_Enterprise_MsgBank"".MessageHeader")

and got this error message

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Article
· Mar 29, 2023 1m read
Named Parameter In SQL with Python

Quick Tips: Total Productive Maintenance

Named parameters can be achieved with SQLAlchemy :

from sqlalchemy import create_engine, text,types,engine

_engine = create_engine('iris+emb:///')

with _engine.connect() as conn:
    rs = conn.execute(text("select :some_private_name"), {"some_private_name": 1})
    print(rs.all())

or with native api

from sqlalchemy import create_engine, text,types,engine

# set URL for SQLAlchemy
url = engine.url.URL.create('iris', username='SuperUser', password='SYS', host='localhost', port=33782, database='FHIRSERVER')

_engine = create_engine(url)

with _engine.connect() as conn:
    rs = conn.execute(text("select :some_private_name"), {"some_private_name": 1})
    print(rs.all())

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"SELECT %SYSTEM.SQL_TableExists('table name') "could work as expected under SQL shell,

but for "CALL %SYSTEM.SQL_TableExists('table name')" does not work (not any error reported, it just show nothing).

Is there any reason why CALL could not be applied to a stored procedure?

Thanks.

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Hello,

We have a need to track Database changes over time - down to the SQL level of granularity if possible. Such as: User xyz runs routine ^abc and we get something similar to a changelog that tells us: table A had this value updated, insert, update etc....

Is that possible using IRIS level tools (Audit Log, Journal File, etc...) , is there a way to convert the global sets and kills from the journals into SQL level changes?

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I am very new to IRIS. We are developing a PHP application that connects to an IRIS instance of one of our vendors. I am having trouble with a specific table. When I need to query this specific table for specific fields, I am receiving an error. However, if I change the call to get all columns (`*`), there is no error. I get 37K records returned.

Error:

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Let's say we have two serial classes, one as a property of another:

Class test.Serial Extends %SerialObject
{
Property Serial2 As test.Serial2;
}

Class test.Serial2 Extends %SerialObject
{
Property Property As %String;
}

And a persistent class, that has a property of test.Serial type:

Class test.Persistent Extends %Persistent
{

Property Datatype As %String;

Property Serial As test.Serial;

}

So it's a serial, inside a serial, inside a persistent object.

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Hi All,

I have two tables LB_TestSet and LB_Transfer

LB_Transfer has a list if TestSet row IDs, so i am doing the following join

SELECT 
LBTS_RowID,
,LBTS_CollectedDate
FROM SQLUser.LB_TestSet 
JOIN SQLUser.LB_Transfer ON ($LISTBUILD(LBTS_RowID) %INLIST LBTR_TestSetList)
WHERE LBTS_CollectedDate BETWEEN '2019-01-01' AND  '2019-05-10'

Without the date filter the query returns data, but if i add the date filter no data is returned

I also tried using %INTERNAL, %EXTERNAL TO_DATE('2009-01-01','YYYY-MM-DD')

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Hi:

I have an sql outbound adapter. Sometimes we have trouble connecting to the database.

The timeout in develpment is set to 15 seconds in live it is 150 seconds as it is an always connected Buisness operation.

I thought adding E=S or/and X=S would suspend the message. Why does it not?

Is the only way around then adding something to the buisness operation itself/ creating a customised SQL buisness operation rather than EnsLib.SQL.OutboundAdapter?

Thanks

Mark

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Hello everyone,

I am looking for the syntax or the way to use a class created in the "BNA" Namespace (my application) from the %SYS Namespace.

Here is the context:

I have a "BNA" application contained in the "BNA" NS, this application provides a user creation functionality. This feature creates both the user in a table in the application and in the Iris system.

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Question
· Feb 1, 2023
NEED NUMBER ROWS IN SQL SELECT

Hi guys,

I'm trying find a way to create a row with the number of each row.

For example:

In the SQL above, i want a way to create a collum with the number of corresponding row, in this case:

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In SQl SERVER i can use FOR, RANK or ROM_NUMBER to do this, but, i can't find a way to do the same in cache SQL.

Can someone help me?

Thank you.

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Question
· Jun 14, 2017
SQL Query for Range

Hello,

I have a question related to running an SQL query for range of data.

I am running a query like:

Select A,B from table_name where A>=12345 AND A<=12390

- Where A and B are my two of the properties under the mentioned table/class definition

- A is an integer property

Question: The result of the above query does not return me all the values between the mentioned range of integer though I do have all the values in that range. I see that some of the values are missing in result.

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