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Robert Cemper · Nov 29, 2017

I'm not an expert on callout but deep back in history I believe to remember that what ever you
transfer is in wider sense a single item. If string structured by $p() or $lb().
You my take a closer look to %XML.SAX.* classes.
The highest structure is $LB(). Which is a string under cover.
And take care of the 32k limit 

Robert Cemper · Nov 27, 2017

I'd suggest to use $LB() if you are not hit by the LongString limit.

why: all packaging, selection,.... is already done and "hard wired" in C++ 
with $C() you may re-invent $LB() or $Piece() or similar. And you have to do it in COS.
Same applies to local array where  you may iterate over the structure in COS again.

Nothing against COS but C++ (in COS Functions) IS faster
 

Robert Cemper · Nov 26, 2017

A few recommendations:
#2) save you original Global as you do otherwise.  [Just to be Save]
#1)  In Studio Copy class has a checkbox to copy Storage Definition (=Globals) . Set it.
  In the new class add ClassParameter MANAGEDEXTENT=0 ;

/// The <var>MANAGEDEXTENT</var> parameter can be set to 0 (zero) to cause the Extent Manager
/// to ignore this class. If set to 1 then the Extent Manager will register globals used by
/// the class and detect collisions. Unmanaged extents (MANAGEDEXTENT = 0) are not checked.
/// Currently, only classes using default storage (%Library.CacheStorage) can be managed.
Parameter MANAGEDEXTENT As INTEGER [ Constraint = "0,1", Flags = ENUM ] = 1;
 

So the old and the new class use the same Globals.
Now go on with #3  to #6

If you miss something in refactoring the damage should be limited as you just change names not the Storage in Globals.
Assuming the change of ClassName is all you do.

Robert Cemper · Nov 24, 2017

For %BuildIndices you may provide a list  or use default. it doesn't affect sequence

example from Sample.Person.1.Int

%BuildIndices(pIndexList="",pAutoPurge=1,pLockFlag=0,pJournalFlag=1,pStartID="",pEndID="",pIgnoreIndexList="") public {
if ($listlength(pIndexList)=1)&&($listget(pIndexList,1)="") { return 1 }
Set class=$classname(),tBuildFlags=1,tBuildFlags(class)=$c(0,0,0,0,0,0)
Set tPtr=0,tStatus=1,pJournalFlag=''pJournalFlag
While $listnext(pIndexList,tPtr,tIndex) {
continue:tIndex=""
If '$d(^oddCOM(class,"i",tIndex)) {
Set tStatus=$select(+tStatus:$$Error^%apiOBJ(5066,class_"::"_tIndex),1:$$AppendStatus^%occSystem(tStatus,$$Error^%apiOBJ(5066,class_"::"_tIndex)))
}
}
If ('tStatus) RETURN tStatus
if $listfind(pIndexList,"$Person") { set $Extract(tBuildFlags(class),1)=$c(1) }
if ((pIndexList="")||($listfind(pIndexList,"FCOL"))),'$listfind(pIgnoreIndexList,"FCOL") { set $Extract(tBuildFlags(class),2)=$c(1) }
if ((pIndexList="")||($listfind(pIndexList,"NameIDX"))),'$listfind(pIgnoreIndexList,"NameIDX") { set $Extract(tBuildFlags(class),3)=$c(1) }
if ((pIndexList="")||($listfind(pIndexList,"SSNKey"))),'$listfind(pIgnoreIndexList,"SSNKey") { set $Extract(tBuildFlags(class),4)=$c(1) }
if ((pIndexList="")||($listfind(pIndexList,"ZipCode"))),'$listfind(pIgnoreIndexList,"ZipCode") { set $Extract(tBuildFlags(class),5)=$c(1) }
if ((pIndexList="")||($listfind(pIndexList,"dobx"))),'$listfind(pIgnoreIndexList,"dobx") { set $Extract(tBuildFlags(class),6)=$c(1) }
If ((pIndexList="")||($Ascii(tBuildFlags(class),5))) && '$listfind(pIgnoreIndexList,"$Person") { set $extract(tBuildFlags(class),1)=$c($select((pStartID'="")||(pEndID'=""):1,1:2)) }
Quit ..%BuildIndexInternal(.pLockFlag,.pAutoPurge,.pStartID,.pEndID,.pIndexList,.tBuildFlags,"^Sample.PersonD",1,.pJournalFlag,0) }
 
 

%Save does it straight by ASSCII sorting of index names (lower after Upper case)

See %SaveData(id)  in the generated .int 

Robert Cemper · Nov 23, 2017

as documented in
http://docs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?KEY=...

DATEPART delivers a %Integer value.
Differently to %Date which has different display, logical and ODBC presentation %Integer does not follow any specific presentation but is just Integer and nothing else.
And your input to DATEPART function is in any example the same: the logical value of TimeCreated.

To  cover your expectations you would need to adapt your input yourself. eg by %ODBCOUT() function.
or the related LogicalToDisplay function.

Your expectation that a data type %Integer does a revers research how it was calculated is just un-realistic.

Robert Cemper · Nov 19, 2017

A Total different idea.

if Transaction.Account is defined as Account object (could also be calculated)
     [ Property Account as Account ;   ]

then you may use implicit join for your query. 
it looks like this:

select Account.Name, Account.State, Transaction.Amt, Transaction.Date, Transaction.Service
from Transaction 
left join Account 
    on Account.Id = Transaction.Account  
where Transaction.Account in ( 
    Select Account.Id
     from Account
     where Transaction.Account ->Type is not null
     and Transaction.Account->Id>123456789        
     and Transaction.Account->Id <=323456789     
  )   
and Transaction.Date >= ?
and Transaction.Date <= ?

 
Robert Cemper · Nov 19, 2017

OK, that looks better smiley

now go to Mgmt Portal /SQL and verify for both tables that you see values in column Selectivity (marked)

IF THERE IS NO SELECTIVITY ANY QUERY PLAN IS JUST GUESSWORK.

if this is empty Query Generator just can guess and do a lot of unnecessary extra work.

so got Tune Table click it

and this you get there information that the Query Generator allows to make useful optimizations (marked)

Next enter your specific  query and click to "Show Plan"
that marked information tells you what is happening and Relative Cost qualifies the expected performance. 

This query plan tells you what is really happening.

Robert Cemper · Nov 19, 2017

At  first sight I'd say the Query Generator is right as your Sub Select Just adds some more WHERE conditions.
Your range on Transction.Date  with related index might be much more limiting than your range on Account.Id.
A index on Account.Type might also speed up your query.
 

where Account.Id in (
    Select Account.Name
     from Account

?? Is Account.Name the same as Account.Id  ???  
IN ( ) expects EXACT VALUES !

Suggestion if no done yet: Run tune Table for both tables

Next: publish the generated Query plan.