How does the SQL pre-compiler handle literals?

Folks:

Does anyone know the specifics of how the SQL pre-compiler handles text literals?

I'm particularly interested in how it handles different CCSID's.

Specifically, if I write & compile a program using CCSID 37 with a hard coded literal (say a regular expression), will the literal work when the program is run in a different CCSID that isn't aligned with 37?

I wrote & compiled the following code in CCSID 37 ... and it works fine in that CCSID.

dcl-s var1 varchar (128) inz(' ABCDEFG ');
dcl-s var2 varchar (128);

exec sql
set :var2 = REGEXP_SUBSTR(:var1, '\s+ab(cd)?efg\s*', 1, 1,'i',1);

I then ran it in CCSID 5026 and it also worked ... which I didn't expect (because lower case characters in 5026 don't align with 37).

On a side note ... where are literals stored when the pre-compiler generates source? For instance, in the above statement, where would the regular expression be stored? The only place I can see it is as a comment in the generated source.

Thanks!

david