Embedded SQL in RPGLE pgm

Ok,
I've searched the archives but can't find (or don't know what I'm looking 
for) any examples of an UPDATE statement using field names that I want to 
build.  I know how to do it using a plain SELECT statement and creating a 
literal statement and then running it.  But what I'm trying to do this 
time is something like:
     C/Exec Sql
     C+ UPDATE PUBWRK/WPUSCHEDLE 
     C+ SET %Trim(ctrName) = %Char(retField), 
     C+ %Trim(appName) = %Char(retField)
     C+ WHERE %Trim(dateName) = %Char(inPickupDate)
     C/End-Exec 

but I don't think I'm doing this right at all am I?
Frustrated beyond all belief today...

Ron Power
Programmer
Information Services
City Of St. John's, NL
P.O. Box 908
St. John's, NL
A1C 5M2
709-576-8132
rpower@xxxxxxxxxx
http://www.stjohns.ca/
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