If you want to detect a journal change, it means, you want to do something, when such a change took place.

I think, you could do something like this:

a) Start a process at system start (for example, from %ZSTART), which will handle journal changes
b) In that process, get the current journal file
c) try to open this file
d) if (c) fails, wait a few seconds and then goto c)
e) if (c) succeds,  handle journal file change, then goto b)
   
A simplified routine, but untested (as a suggestion):

journalchanges ; Handle journal file changes

#define SWITCHES $system.Util.GetSwitch()
#define SHUTDOWN ##Expression(2**16)
#define BITAND(%a,%b) $zboolean(%a,%b,1)
   
   set jouFile=$$getCurrentFile()  // get the current journal file
   if jouFile="" Quit              // should not happen, but who knows...
   
   while '$$$BITAND($$$SWITCHES, $$$SHUTDOWN) { // stop, if shutdown is in progress
      open jouFile:"WL":1 // try to get ownership
      continue:'$test     // locked (by the journaling system), we try once again
      close jouFile       // because we were interested in status only
   
      // Now you can use <jouFile> to handle the file change
      // By now, he journaling system uses a new journal file
      
      set jouFile=$$getCurrentFile() // get the new journal file
      if jouFile = "" quit           // just to be on the safe side
   }
   
   quit  // we are done
   
    
getCurrentFile()
{
   try { return ##class(%SYS.Journal.System).GetCurrentFile().Name } catch { return "" }
}

Yes, you have right, thank you for the hint.  One never should add an alternate function without testing it!

The correct form is:

ClassMethod CountQ(node) As %Integer
{
  s end=node
  if $data(@node)#10 { set sum=1 } else { set sum=0 }
  while 1 { set node=$query(@node) quit:node=""||($name(@node,$qlength(end))'=end) if $increment(sum) }
  quit sum
}

Class community.counter Extends %RegisteredObject
{
/// Example:
/// set ^x(1)=111
/// set ^x(3,5)=222
/// set ^x(3,7)=333
/// 
/// The above global has 5 nodes:
/// ^x without a value
/// ^x(1) with value
/// ^x(3) without a value
/// ^x(3,5) with value
/// ^x(3,7) with value
/// 
/// write ##class(community.counter).CountQ($name(^x)) --> 3
/// write ##class(community.counter).CountR($name(^x)) --> 3
/// 
/// Using your example:
/// write ##class(community.counter).CountQ($name(^Locations)) --> 5
/// write ##class(community.counter).CountQ($name(^Locations("USA")) --> 3
/// 
/// 
/// N.B.
/// Recursion is a tricky thing!
/// It helps one to get a clearly laid out solution
/// but you should take care about runtimes.
/// 
/// CountQ(...) is about 4-5 times faster then CountR(...)
/// 
/// --------------------------------------------------------
/// 
/// Return the count of nodes of a global- or a local variable
/// which have a value, using $QUERY() function
/// 
/// node:
/// a local or global variable, example: $na(^myGloabl), $na(abc)
/// or a local or global reference example: $na(^myGlobal(1,2))
/// 
ClassMethod CountQ(node) As %Integer
{
 if $data(@node)#10 { set sum=1 } else { set sum=0 }
 while 1 { set node=$query(@node) quit:node=""  if $increment(sum) }
 quit sum
}

/// Return the count of nodes of a global- or a local variable
/// which have a value, using recursion, using recursion
/// 
/// node:
/// a local or global variable, example: $na(^myGlobal), $na(abc)
/// or a local or global reference example: $na(^myGlobal(1,2))
///       
ClassMethod CountR(node) As %Integer
{
 set sum=0
 do ..nodeCnt($name(@node), .sum)
 quit sum
}

ClassMethod nodeCnt(ref, ByRef sum) As %Integer [ Internal, Private ]
{
 if $data(@ref)#10, $increment(sum)
 set i=""
 while 1 { set i=$order(@ref@(i)) quit:i=""  do ..nodeCnt($na(@ref@(i)),.sum) }
}

}

Of course, the same goes for the other methods, which have a wide (...W) variant

I can see it right now, do you use
- conn.Prepare(...) or
- conn.PrepareW(...) ?

This should be coordinated with your MySQL installation.

Some hints/questions:

• did you installed the correct driver? I mean, do have Cache/Iris and the
  driver the same architecture (32 vs. 64 bit)?

• I'm not an MySQL expert (I do not even have an MySQL DB), so I ask, is
  there any problem with the character size (1 byte vs. 2 bytes/unicode), if
  this applies?

• with a DB-Tool, like WinSQL, try to make an SELECT (as suggested by Eduard Lebedyuk) statement. What is the error message?

HELP: what are the markdown characters?

In the above answer, I put some words between angle braces, now all they are lost!
OK, I try once again with an apostrophe.

1) set stat=conn.Connect("odbcname", "username" ,"password")
"username" is a MySQL user.

5) If the content of the variable "variableX" is an alphanumeric value then put a single quote char (') around the value. Beforehand remove (or replace) all single quotes (with something else) from "variableX".

Some thoughts/hints to your problem:

1) set stat=conn.Connect(, ,
)
is a MySQL user.
Does this user have the rights for UPDATE and INSERT?

2) What are the status codes after
- set sc=conn.Prepare(...) and
- set sc=conn.Execute(...)?

3) Your query-string should have blanks after the table name and also before and after the VALUES keyword.

4) If the variables value1, value2, ... valueN CAN CONATIN a backslash character then you should either duplicate them
set valueX = $replace(valueX, "\", "\") or switch the escaping off at the start your query-string :
set pQuery="SET sql_mode='NO_BACKSLASH_ESCAPES'; INSERT INTO ..."
see also: https://dev.mysql.com/doc/refman/5.7/en/sql-mode.html

5) If the content of the variable is an alphanumeric value then put a single quote char (') around the value. Beforehand remove (or replace) all single quotes (with something else) from .

To make a connection to a MySQL Database via ODBC is easy.
In the next steps I assume you are on a Windows system (Linux/Unix is similar):

1) download (https://dev.mysql.com/downloads/connector/odbc/) and install the proper ODBC driver
2) go to ControlPanel-->AdministrativeTools-->DataSources(ODBC)
3) select the SystemDNS-Tab, click Add
- give a unique name to this datasource (and remember it for step 4)
- fill in the necessary fields as desired
4) use the %SQLGatewayConnection class to get/put your data from/into MySQL,
something like:

 set gtw=##class(%SQLGatewayConnection).%New()
 if gtw.Connect(datasourceName, user, pass) {
    // do your work
 } else {
    // can't connect
 }

No, it works and all installations but yes, it needs 8 Bit  characters.

A simple command like

write "abcd"

writes out four 8-Bit characters, independent of your installation (8-Bit or Unicode)

On Evgeny Shvarov's PC, a command like

write "Физз"

would write out four 16Bit characters, in sum 2*4 = 8 characters, each with 8 Bits

It depends on, what are the requirements...
Usually we want to occupy as few (RAM) bytes as possible.
Yes, it uses the fewest characters but far more bytes as Robert's solution.

We can save some more bytes:

f i=1:1:100 w $p(i_",Fizz,Buzz,FizzBuzz",",",i#5=0*2+'(i#3)+1),!

"640K ought to be enough for anybody." Oh, I meant, 64 bytes should be enough.

If you need to reorder a given set of characters (as above, from "12/03/2019" to "2019-03-12") then the $translate(...) function, used in "backward-mode" is your best friend.

set p="12/03/2019"
write $tr("abcd-ef-gh","ef/gh/abcd",p) --> 2019-12-03

Your gain: 50% of speed.

Nota bene

(1) $translate(inputdata, fromChars, toChars) --> outputdata
(2) $translate(toSequence, fromSequence, inputdata) --> outputdata

Where (1) is the Forward-Mode (the regular usage) and (2) the Backward-Mode

What do you mean with "from Code I am getting"? From which Code?
["\"KY\",\"TN\",\"AL\",\"GA\""] seems to be the same as the terminal output, except the quote chars are escaped...