How can I code without:

quit:$$$ISERR(sc) sc

it's basically 5% of the code I write.

How about

do:condition ..Method()

Your options are:

• Contact your nearest InterSystems office for discussion and WRC account. List of offices.
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You can use negative integers to subtract hours. DATEADD also words with timestamps:

write $SYSTEM.SQL.DATEADD("hour", -3, "2019-03-09 10:00:00")
>2019-03-09 07:00:00

ODBC log and maybe Audit log can contain additional information.

IRIS Text Analytics/iKnow and Analytics/DeepSee are enabled on per-application basis. Interoperability/Ensemble/HealthShare are enabled on a per-namespace basis.

First you need to get default application from the namespace:

set namespace = "USER"
set app = $System.CSP.GetDefaultApp(namespace) _ "/"

And then call one of these methods:

do EnableIKnow^%SYS.cspServer(app)
do EnableDeepSee^%SYS.cspServer(app)

If you want to enable Interoperability/Ensemble call:

set sc = ##class(%EnsembleMgr).EnableNamespace(namespace,1)

You can do that in Analyzer.

Choose the row/column you want displayed this way, click on it's settings and set italic header:

You can use CreateDirectoryChain method of %File class to create directory tree instead of several calls to CreateDirectory.

Link to file doesn't need for a file to exist, but the containing directory must exist and should be writable by a OS user (cacheusr in uyour case probably).

I'd try to write into a temp dir first, where you're sure you have access:

set file = ##class(%File).TempFilename("pdf")
set sc = stream2.LinkToFile(file)
quit:$$$ISERR(sc) sc

record value of file somewhere (output to display or store in global) and check if the file was created).

%Save method also returns status, you should return it instead of $$$OK:

set sc = stream2.%Save()
quit sc

Check this table of Ens resources. Your role should have some of these resources to give user access to Ensemble pages.

I try to separate SQL from ObjectScript code. So mainly, I'm using queries, for example:

/// Some report. To display in terminal call:
/// do ##class(class).reportFunc().%Display()
Query report(date As %String = {$zd($h-1,8)}) As %SQLQuery(SELECTMODE = "ODBC")
{
SELECT
  ID,
  Value,
  EventDate
FROM myTable
WHERE EventDate>=TO_POSIXTIME(:date,'YYYYMMDD') AND EventDate<TO_POSIXTIME(:date+1,'YYYYMMDD')
ORDER BY EventDate
}

Queries can be calles from ObjectScript using autogenerated Func method:

/// Really %sqlcq.<NAMESPACE>.cls<NUMBER>
#dim rs As %SQL.ISelectResult
set rs = ..reportFunc(date)
//do rs.%Display()

while rs.%Next() {
    write rs.ID,!
}

I found this approach improves readability of the codebase. More about queries in this article.

Special case - one value.

Sometimes you don't need a resultset, but one value. In that case:

If you know ID it's possible to use GetStored method:

set value = ##class(test).<PropertyName>GetStored(ID)

If you know unique indexed value but don't know ID, it's possible to get id with Exists method:

ClassMethod <IndexName>Exists(val, Output id) As %Boolean

And after that use GetStored method.

More on auto-generated methods, such as GetStored and Exists in this article.

Finally, if you can't use above methods or you need one value but it's an aggregate, use embedded SQL if it's a short SQL and Query if it's long.

Okay, even if the classes/globals are the same there's a solution. Let's say you have Sample.Person class in namespaces SAMPLES and USER, each with their own data:

Class Sample.Person Extends %Persistent
{

Property Name;

Storage Default
{
<Data name="PersonDefaultData">
<Value name="1">
<Value>%%CLASSNAME</Value>
</Value>
<Value name="2">
<Value>Name</Value>
</Value>
</Data>
<DataLocation>^Sample.PersonD</DataLocation>
<DefaultData>PersonDefaultData</DefaultData>
<IdLocation>^Sample.PersonD</IdLocation>
<IndexLocation>^Sample.PersonI</IndexLocation>
<StreamLocation>^Sample.PersonS</StreamLocation>
<Type>%Library.CacheStorage</Type>
}

}

And you want to query both from the USER namespace. In that case create a new class extending Sample.Person in the USER namespace and modify storage like this:

Class Utils.SamplesPerson Extends (%Persistent, Sample.Person)
{

Storage Default
{
<Data name="PersonDefaultData">
<Value name="1">
<Value>%%CLASSNAME</Value>
</Value>
<Value name="2">
<Value>Name</Value>
</Value>
</Data>
<DataLocation>^["SAMPLES"]Sample.PersonD</DataLocation>
<DefaultData>PersonDefaultData</DefaultData>
<ExtentSize>200</ExtentSize>
<IdLocation>^["SAMPLES"]Sample.PersonD</IdLocation>
<IndexLocation>^["SAMPLES"]Sample.PersonI</IndexLocation>
<StreamLocation>^["SAMPLES"]Sample.PersonS</StreamLocation>
<Type>%Library.CacheStorage</Type>
}

Note that DataLocation, IndexLocation, IdLocation and StreamLocation point to the SAMPLES namespace.

Now query:

SELECT *
FROM Utils.SamplePerson

Would fetch data from SAMPLES namespace.