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#SQL

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

All time

Class ICT.Experiments.A Extends %Persistent
{
Property Name As %String;
Property Collection As list Of ICT.Experiments.B;
Property Collection2 As array Of ICT.Experiments.C;
}

Class ICT.Experiments.B Extends %Persistent
{
Property Name As %String;
}

Class ICT.Experiments.C Extends %Persistent
{
Property Name As %String;
}

I have the classes above and I can select columns from the array collection by using two joins as follows:

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If I have defined a class query in one of my classes and I want to use that query from a method of another class, what are the pros and cons of using the %SQL.Statement interface versus the %Library.ResultSet interface?

I believe %SQL.Statement is the newer interface.

So if the old way is:

USER>s rs=##class(%Library.ResultSet).%New("%Library.File:FileSet")
 
USER>s sc=rs.Execute("c:\s\","*.txt")
 
USER>w sc
1
USER>while rs.%Next() {w !,rs.Data("Name")}

...

then the new way is:

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Overview

Encryption of sensitive data becomes more and more important for applications. For example patient names, SSN, address-data or credit card-numbers etc..

Cache supports different flavors of encryption. Block-level database encryption and data-element encryption. The block-level database encryption protects an entire database. The decryption/encryption is done when a block is written/read to or from the database and has very little impact on the performance.

With data-element encryption only certain data-fields are encrypted. Fields that contain sensitive data like patient data or credit-card numbers. Data-element encryption is also useful if a re-encryption is required periodically. With data-element encryption it is the responsibility of the application to encrypt/decrypt the data.

Both encryption methods leverage the managed key encryption infrastructure of Caché.

The following article describes a sample use-case where data-element encryption is used to encrypt person data.

But what if you have hundreds of thousands of records with an encrypted datafield and you have the need to search that field? Decryption of the field-values prior to the search is not an option. What about indices?

This article describes a possible solution and develops step-by-step a small example how you can use SQL and indices to search encrypted fields.

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Question
· Feb 28, 2020
SQLCODE Error -400

I have a code block in a BPL. I have the below SQL and code. All variables have been declared and set. When I run the SQL, if there are no values returned, I get 100 for the value of SQLCODE when I perform the FETCH, which is correct. If values are returned, I get a -400 error when I perform the first FETCH. I've investigated, but cannot find the reason for a -400 error. Hoping someone out here understands this and knows what's wrong.

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Customer is experimenting with %vid variable for selecting row numbering for sql queries. Basically he's trying to implement paging functionality.

He is confused that select %vid from (select ...) returns dummy number whilst select *,%vid from (select...) returns correct data.

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Last week, we announced the InterSystems IRIS Data Platform, our new and comprehensive platform for all your data endeavours, whether transactional, analytics or both. We've included many of the features our customers know and loved from Caché and Ensemble, but in this article we'll shed a little more light on one of the new capabilities of the platform: SQL Sharding, a powerful new feature in our scalability story.

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Article
· Apr 4, 2023 2m read
InterSystems SQL Cheat Sheet

Hi developers!

As you know InterSystems IRIS besides globals, object, document and XML data-models also support relational where SQL is expected as a language to deal with the data.

And as in other relational DBMS InterSystems IRIS has its own dialect.

I start this post to support an SQL cheatsheet and invite you to share your favorites - I'll update the content upon incoming comments.

Here we go!

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Hi All,

I have a general query in regards to developers experience on extracting data from cache databases and the most efficient way to do so. I work with a number of clients who have applications with cache databases and require the data off the host system and onto data warehouse platforms for research and analysis. Often they require the data in source state which means the extracts are often simply a table scan of the entire database table without any aggregation or manipulation.

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With the release of InterSystems IRIS Cloud SQL, we're getting more frequent questions about how to establish secure connections over JDBC and other driver technologies. While we have nice summary and detailed documentation on the driver technologies themselves, our documentation does not go as far to describe individual client tools, such as our personal favourite DBeaver. In this article, we'll describe the steps to create a secure connection from DBeaver to your Cloud SQL deployment.

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Whenever I try to run a simple query on a production database table, I get a timeout 504 error. I'm using the SQL interface in Ensemble. One of the queries is a simple SELECT TOP 10. Even SELECT COUNT(*) gives a timeout.

I have tried to run the SQL Runtime Statistics, but this gives me a timeout as well.

Does anyone have an idea where I might look to find what is causing this?

Thanks in advance,

Best regards

Glenn van Bavel,

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Question
· Jan 6, 2020
ODBC Providers for SQL Server

Where can i get the latest odbc providers from SQL Server 2012/2016?

I see some posts on line to an ftp site out there but I am unsuccessful at getting access to it. I have a version loaded on my server but get errors when querying cache'.

"[Cache ODBC][State : 22005][Native Code 22005]"

Any help would be appreciated.

the one we have might be version 2014.01.05851 64 bit (would that make sense?)

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I want to override the Get and Set methods of a class property. The class maps to a pre-existing global. The property is defined like so:

Property Invalid As %Library.Boolean;

with the property mapping to a node like ^GLOBAL(Code,"INVALID")=1
Code is a property in the same class.

The value can be 0 or 1 or the node might not exist. When it doesn't exist I want the value of the SQL field to come out as 0 (false).

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Hi,

I'm developing an integration between Caché servers by ODBC conection, and I have the following problem.

In this call:

call COSClass_Methode('222169^^98^155^64530^06:30^021542987897458855441112877855^1^0^281992^GC')

the ODBC driver is truncating the string to 50 characters.


If I run this same command with $system.SQL.Shell(), this doesn't occur.
I did a test creating several parameters for COSClass_Methode, and they all have a 50 character limitation.

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I'm running this code in our application, and in the terminal:

>set query="SELECT * FROM PMG_Data_Private.RemitInstance WHERE (VoucherNumber %INLIST ? SIZE ((10)))"

>set tRS = ##class(%ResultSet).%New("%DynamicQuery:SQL")

>set ok=tRS.Prepare(query)

>d $system.Status.DisplayError(ok)

ERROR #5540: SQLCODE: -76 Message: Cardinality mismatch between the SELECT-list and INTO-list
SQLTEXT: SELECT * FROM PMG_Data_Private.RemitInstance WHERE (VoucherNumber %INLIST ? SIZE ((10)))

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I am trying to fetch the data from cache database. But i got the error like "CSP application closed the connection before sending a responce".

Below is the query.

SELECT
CallbackComment
FROM SQ.CBPhoneResult_View Where PhoneDateODBC = '2018-04-09'

I have investigated and found that "CallbackComment" contains the special character single quotes " ' " for one result and due to this i got this error.

In this field data is enter by customer. so we cannot restrict them like Do Not use single quotes.

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