Maybe this is well known but wanted to help share.

Consider that you have the following persistent class defintions

An Invoice Class with a property reference to Provider

Class Sample.Invoice Extends (%Persistent, %Populate)
{
Parameter DSTIME = "AUTO";
Property InvoiceNumber As %Integer(MINVAL = 100000) [ Required ];
Property ServiceDate As %Date(MINVAL = "+$h-730") [ Required ];
Index InvoiceNumber On InvoiceNumber;
Property Provider As Sample.

When I'm asked questions about SQL, I like Intersystems staff at the WRC, generally ask about the Query Plan.  My feeling is that even before you run a query you should examine the results of Show Plan to confirm that the code is going to give me the results in the manner I would expect.  If I expect it to leverage an index and I see that it is not then I go back and look at what I might have done incorrectly and try to re-write the query to get the index behavior I'm looking for.

I  have a DeepSee KPI defined based on %DeepSee.KPI following the documentation http://docs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?KEY….  I've then enabled the KPI on a dashboard by adding a Widget where the data source is the KPI.  Currently the ability to show a Detail Listing is implemented by the call back  %OnGetListingSQL.  This method documents the parameter

pListingName is the name of the listing to display. This is reserved for future use.

I interested on how others feel on this subject.  In general terms when you have a class that extends from %XML.Adaptor and you call XMLExport no validation is automatically done as part of the XMLExport process.  As an example if you do the following

SAMPLES>S tPatient=##Class(Sample.Person).%New()
 
SAMPLES>Set tPatient.Name="asdfghjklqwrrrrokkfkljbvkfbjflkbjflkbjblkjblkjdblkjblkcn l nn klkjdfkbjdlkbjlkbj"
SAMPLES>w tPatient.XMLExport(,",indent")
<Person>
  <Name>asdfghjklqwrrrrokkfkljbvkfbjflkbjflkbjblkjblkjdblkjblkcn l nn klkjdfkbjdlkbjlkbj</Name>
</Person>

where tPatient.