How would you like to solve it, using ObjectScript?

ClassMethod Test()
{
  s C = 2500,
    r = 0.5,
    S = 3000000,
    T = 35,
    W = 5
  w $$maxWeddingCost(C, r, S, T, W),! ; => 93278.3281405256664

  s S = 2000000
  w $$maxWeddingCost(C, r, S, T, W),! ; => 174425.0762746580325
    
maxWeddingCost(C,r,S,T,W) s r=r/100,a=1+r**12,b=a**(T-W) q a**W-1/r*C+$$LEAST^%qarfunc(0,b-1/r*C-S/b)
}

We have our own challenge with very specific conditions and goals: #Code Golf
And what is the purpose of your challenge, I do not quite understand: speed, code size, etc? Rewriting the code in ObjectScript is too simple and not interesting.

ClassMethod esthetic(num = 441) As %String
{
  set estheticBases=""
  for base=2:1:10{
    set digits = $$toBase(num, base)
    if $$isEstheticInBase(digits) set estheticBases=estheticBases_$listbuild(base)
  }
  quit $listtostring(estheticBases)
  
toBase(n,base)
  ; Convert number n to a given base and return the digits as a list.
  set digits=""
  while n {
    set digits=(n#base)_digits,
        n=n\base
  }
  quit digits
isEstheticInBase(digits)
  ; Check if the given list of digits is esthetic.
  for i=2:1:$length(digits){
      if $zabs($extract(digits,i)-$extract(digits,i-1))'=1 {
          return 0
      }
  }
  return 1
}

The calculateTotalSavingsAtTime method can be shortened because initialPrincipal is always 0:

    public static double calculateTotalSavingsAtTime(double initialPrincipal, double r, double monthlyDeposit, int timeMonths) {
        return monthlyDeposit * ((Math.pow(1 + r, timeMonths) - 1) / r) + initialPrincipal * Math.pow(1 + r, timeMonths);
    }

Try this:

ClassMethod GetTreeInfo(
  pRoot As %String,
  Output pTree,
  ByRef pParms) As %Status
{
  Set MyId=..GetId,pos=1
  &Sql(Select Name,ID into :name,:id from MSDS_COM.Loc where Parent=:MyId)
  Set:SQLCODE (name,id)=""
  if pRoot=""
  {
    Set pTree(0,"ch",1) = ""
    Set pTree(1) = $LB(name,id,1,"","")
  }
  Quit $$$OK
}

For further examples, see the class ZENTest.DynaTreeTest in the SAMPLES namespace.

Through %ZEN.proxyObject is unlikely to work, since the q parameter cannot be disabled in this case

q - output numeric values unquoted even when they come from a non-numeric property

Use your own class, for example:

Class dc.proxyObject Extends %RegisteredObject
{

Property ID As %VarString;

}

set object = ##class(dc.proxyObject).%New()
set object.ID = 123456

set x = ##class(%ZEN.Auxiliary.jsonProvider).%WriteJSONStreamFromObject(.json,object,,,,"aelotw")

Output:

{
  "ID":"123456"
}

I do not observe any differences in the behavior of xDBC and Portal.

Given:

Class dc.test Extends %Persistent
{

Property s1 As %String(MAXLEN = 2, TRUNCATE = 1);

Property s2 As %String(MAXLEN = 2);
}

• insert into dc.test(s1,s2)values('abc','ab')

  Result

  ID	s1	s2
  1	ab	ab

• insert into dc.test(s1,s2)values('abc','abc')

  Result for any JDBC/ODBC tools (DBVisualizer, SQL Data Lens, etc.):

  [SQLCODE: <-104>:<Field validation failed in INSERT>]
  <Field 'dc.test.s2' Truncation (Varchar Value: 'abc ...' Length: 3) > maxlen:  (2)>]

  Result for Management Portal:

  [SQLCODE: <-104>:<Field validation failed in INSERT>]
  
    [%msg: <Field 'dc.test.s2' (value 'abc') failed validation>]

Check your TRUNCATE parameter.

Common Parameters:TRUNCATE
TRUNCATE — Specifies whether to truncate the string to MAXLEN characters, where 1 is TRUE and 0 is FALSE. This parameter is used by the Normalize() and IsValid() methods but is not used by database drivers.

Class dc.test Extends %Persistent
{

Property s1 As %String(TRUNCATE = 1);

Property s2 As %String;

ClassMethod Test()
{
  d ..%KillExtent(,$$$YES)

   s t=..%New()
   s t.s1=$tr($j("",51)," ","a")
   s sc=t.%Save()
   w "s1: ",$s($$$ISERR(sc):$system.Status.GetErrorText(sc),1:"OK"),!

   s t=..%New()
   s t.s2=$tr($j("",51)," ","a")
   s sc=t.%Save()
   w "s2: ",$s($$$ISERR(sc):$system.Status.GetErrorText(sc),1:"OK"),!
}

}

USER>d ##class(dc.test).Test()
s1: OK
s2: ERROR #7201: Datatype value 'aaaa..aa' length longer than MAXLEN allowed of 50
    > ERROR #5802: Datatype validation failed on property 'dc.test:s2', with value equal to "aaaa..aa"

The same error occurs in the Management Portal.

MAXLEN is not applicable for %GlobalCharacterStream (Blob). You will get compilation error #5480

I noticed that you are using the {Stream} syntax, which is typical for trigger code or calculated field.
Could you check the following code at your place:

Class dc.test Extends %Persistent
{

Property stream As %GlobalCharacterStream;

Trigger NewTrigger1 [ Event = INSERT ]
{
 i $IsObject({stream}) {
   s t={stream}
   s ^||tmp=t.Size
 }
}

ClassMethod Test()
{
  d ..%KillExtent(,$$$YES)
  
  s f=##class(%Stream.FileBinary).%New()
  d f.LinkToFile("C:\test.jpg")
  
  &sql(insert into dc.test(stream) values(:f))
  i 'SQLCODE {
    &sql(select CHAR_LENGTH(stream) into :len from dc.test where %id=1)
    w len," ",^||tmp,!
  }
}

}

I have saved a 16 MB file without any problems:

USER>d ##class(dc.test).Test()
16446809 16446809

String Length Limit

USER>w $system.SYS.MaxLocalLength()
3641144

The resulting archive is easily recognized/unpacked in WinRAR, 7z:

s f=##class(%Stream.FileCharacterGzip).%New()
s f.TranslateTable="UTF8"
s f.Filename="C:\test.gz"
d f.WriteLine("test")
d f.Write("Привет Caché")
d f.%Save()

I think it will also be useful to mention here the links to the documentation:

• Optimizing SQL^IRIS (Best Practices for Improving SQL Performance, Configure SQL Performance Options, etc.)
• Performance and Programming Considerations^Caché (for ECP)
• Performance tips for Business Intelligence^IRIS (DeepSee)
• Performance&Security Tips and Information^IRIS (for Persistent Classes)

I would like to supplement the above with such parameters as STORAGEDEFAULT, SQLTABLENAME, and SQLPROJECTION: Storage and SQL Projection of Collection Properties

However a collection property is actually stored, the property can be projected as a column in the parent table, as a child table, or in both ways (as of release 2022.1, this is true for both list and array properties). To control this, you specify the SQLPROJECTION parameter of the property.

Thanks for the hint, I fixed it.
By the way, your code can be reduced to 173:  f i=$i(r):1:a

There is no limit to perfection.

By the way, your code shows 175 characters, where did the number 174 come from?

Ah, got it.

I improved my score to 179 (see above).

Have you used a test case?