%SUBST Varchar and RPG

[Chris]

Few Issues I'm running into w/VARCHAR and RPG.

Trying to %SUBST on a VARCHAR column in a table. IE.
%Subst(VARCHARFLD:1:15). It bombs, then after a little reading I found
out why (stores the length). So, I thought I could convert it to Char
IE, %CHAR(VARCHARFLD), the Compiler says no. So then I tried the
compiler option, CVTOPT(*VARCHAR). %SUBST worked, but when I tried to
update the DB Table, I received a data mapping error.

What I'm looking for is a way to convert the VARCHAR to a CHAR so I
can do SUBST. Am I missing something? V5R3 If it helps.

Tx

Chris

[Chris Pando]

Post by Chris
Few Issues I'm running into w/VARCHAR and RPG.
Trying to %SUBST on a VARCHAR column in a table. IE.
%Subst(VARCHARFLD:1:15). It bombs, then after a little reading I found
out why (stores the length). So, I thought I could convert it to Char
IE, %CHAR(VARCHARFLD), the Compiler says no. So then I tried the
compiler option, CVTOPT(*VARCHAR). %SUBST worked, but when I tried to
update the DB Table, I received a data mapping error.
What I'm looking for is a way to convert the VARCHAR to a CHAR so I
can do SUBST. Am I missing something? V5R3 If it helps.
Tx
Chris

http://publib.boulder.ibm.com/iseries/v5r1/ic2924/books/c0925083163.htm#HDRUSEVLF

Look at Figure 84

The first two bytes of the variable length field are the length, the
rest the data. You use a data structure to break the field into
a decimal variable and a character variable, and substring the
character variable. If you are going to change/update the field
in the database, you are responsible for changing the decimal variable
to the appropriate length.

varChar = string;
varDec = %Len(%TrimR(string));


HTH,

Chris

Chris
--

[Steve Richter]

Post by Chris
Few Issues I'm running into w/VARCHAR and RPG.
Trying to %SUBST on a VARCHAR column in a table. IE.
%Subst(VARCHARFLD:1:15). It bombs, then after a little reading I found
out why (stores the length).

I think it bombed because the length was less than 15.

Post by Chris
So, I thought I could convert it to Char
IE, %CHAR(VARCHARFLD), the Compiler says no. So then I tried the
compiler option, CVTOPT(*VARCHAR). %SUBST worked, but when I tried to
update the DB Table, I received a data mapping error.
What I'm looking for is a way to convert the VARCHAR to a CHAR so I
can do SUBST. Am I missing something? V5R3 If it helps.

should just be able to copy the varying field into the char field.

-Steve

[Brian]

Post by Chris
Few Issues I'm running into w/VARCHAR and RPG.
Trying to %SUBST on a VARCHAR column in a table. IE.
%Subst(VARCHARFLD:1:15). It bombs, then after a little reading I found
out why (stores the length). So, I thought I could convert it to Char
IE, %CHAR(VARCHARFLD), the Compiler says no. So then I tried the
compiler option, CVTOPT(*VARCHAR). %SUBST worked, but when I tried to
update the DB Table, I received a data mapping error.
What I'm looking for is a way to convert the VARCHAR to a CHAR so I
can do SUBST. Am I missing something? V5R3 If it helps.
Tx
Chris

You could append 15 blanks to insure your substring does not reach past
the end of the data:

%subst( varcharfld + ' ' : 1 : 15 )

[Chris]

Thanks all, I use the suggestions noted.

BTW, IMHO IBM should mod %CHAR to convert VARCHAR to character and
another bif (or add another format to %CHAR) to convert CHAR to
VARCHAR.

Chris

[Ken]

Hi Chris -

Post by Chris
BTW, IMHO IBM should mod %CHAR to convert VARCHAR to character and
another bif (or add another format to %CHAR) to convert CHAR to
VARCHAR.

Why? A straight eval does that.

[Chris]

Hmm, correct. Maybe I went about the SUBST issue the wrong way.... Oh
well, leave and learn.

Chris

[Ken]

Hi Chris -

Post by Chris
Hmm, correct. Maybe I went about the SUBST issue the wrong way.... Oh
well, leave and learn.

If the varying length field *could* contain as much data the constant
start position and length allow for, the compiler cannot issue an
error. It has to be a run-time error if the length requested exceeds
the current length of the data (just as it would be a run-time error
if a variable start position or length attempted to go beyond the end
of a fixed-length field).

I would code something like:

if %len(varying) >= 15
eval fixedlength = %subst(varying:1:15)
else
eval fixedlength = varying
endif

Of course if fixedlength has a length of 15 or less, all you need is a
straight eval:
eval fixedlength = varying