Alexandr Ladoshkin · Nov 23, 2017
Indexing null value

Dear community!

I have problem with index NULL value.  Unique index doesn't work for this case.  If I use insert and one of parameter is "NULL". Message of constraint doesn't appear and row is inserted into table successfully.  How Can I use index with NULL?

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Neerav Adam Verma · Mar 5, 2019
PrimaryKey vs Idkey

Just wondering an Insight in the difference between these two indexes

IdKey / PrimaryKey

Property Identifier As %Integer

Index Index1 on Identifier [Idkey]

Index Index2 on Identifier [PrimaryKey]

What's the difference?

1. If I don't have Index1 and only have Index2,  then cache does still make its own id.
So how and why  do I ever use the PrimaryKey.  In Joins ??

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Hi guys!

Unique, PrimaryKey and IDKey?
In what contexts does it apply?

IDKey sets the registry key access to the store.
PrimaryKey, Unique, and IDKey define the uniqueness in the records, but what is correct?

I use everyone? What is the context of each?

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Hi, folks!

Suppose you have a Caché class with %String property which contains relatively large text (from 10 to 2000 symbols).

The class:

Class Test.Duplicates Extends %Persistent 


Property Text As %String (MAXLEN = 2000);


And you have thousands of entries.

What are the best options to find entries which are duplicates on this property?

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I have a persistent class that represents cities across the United States.  It is below, but basically has a City Id, Name, Lat, Lon and a few other unimportant fields for this issue.  Anytime I attempt to query on the Latitude or Longitude it immediately returns no results.  My first thought was that it was a casting issue so I tried casting both sides to floats, ints, even strings and in all cases it immediately comes back with no results.  I then decided to cast it to a string and attempt a like statement thinking it might be something about how floats are handled, but still no joy.  Any

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I know of the existance of (ELEMENTS) to create an index from a list, but I actually would like to index the content of an element of a list. Is it possible?


My scenario:

Property Test As list of TestList;

Property Name As %String;
Property Surname As %String;

I would like to have an  index based on the TestList.Name. If I try using

Index NewIndex On Test(ELEMENTS)

it will create an index with Name and Surname in it, but I just want to have an index with the name. Is it possible? 

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Hello, community!

I've stumbled on some unexpected behavior, and decided to check with you if this is normal. Basically, I'm rebuilding indices and the result is not journaling (which leads to missing indices at shadow server).

The $ZV is "Cache for UNIX (Red Hat Enterprise Linux for x86-64) 2015.2.1 (Build 705U) Mon Aug 31 2015 16:53:38 EDT"

I have an example class 

Class tmp.A As %Persistent;

Index IP1 On P1;

Property P1 As %String;

for example there is one object which have P1 = 1, so

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I'm using Cache SQL and want the ability to choose a specific index.

I've boiled the problem down to one table and simplified the query down to

FROM Registration.PatResp
WHERE SchedApptNum=8450022


SchedApptNum is indexed, but instead of using that column, "Show Plan" indicates that it's looping through the entire Registration.PatResp table on Id (the primary key for the table).

I've done a tune-table with no change.

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Consider I have a class Package.Data with Property UniqueStringValue as %String.

I introduced the Index for this property:

 Index ValueIndex on UniqueStringValue [Unique];

It works well.  But if I try to check if there is an object with the certain value in code like this:

if ##class(Package.Data).ValueIndexExists(value)  

this expression fails, if value="value", even if there is an instance with instance.UniqueStingValue="Value"

How can I set the index to prevent saving case sensitive values in this class?

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