7/27/2019 Tips and Techniques Dealing With COPY and Embedded
SQL
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Tips and Techniques: Dealing with /COPY and Embedded SQL
Contributed by Robert CozziTuesday, 06 July 2004Last Updated
Tuesday, 06 July 2004
/INCLUDE solves problems with the SQL preprocessor.
One of the most frequently asked questions I get is how to use
the nested/COPY feature in RPG IV. This feature allows you to use
/COPY to copy a sourcemember and, in the copied source member, also
have another /COPY directive thatcopies in yet another member.
This capability is supported up to 2,048 levels deep and is
controlled withthe COPYNEST keyword on the Header specification.
The COPYNEST keyword allowsyou to adjust the default maximum
nesting level up or down (the default is32).
Nested /COPYs are powerful and very useful; however, the popular
IBM SQLpreprocessor does not support nested /COPY statements.
Therefore, manyapplications and third-party software tools cause
the SQL preprocessor togenerate an error during the preprocessor
"compile" phase. This can createhours, if not days, of headaches
and research for those who run into thisproblem.
To resolve this problem, IBM introduced the /INCLUDE directive.
Thisdirective is unknown to the SQL preprocessor. Since the SQL
preprocessor waswritten prior to the introduction of /INCLUDE, this
directive simply passesunnoticed through the SQL preprocess phase
of the compiler. Here's all you have to do:
Old /COPY style:/COPYQRPGLESRC,xtools
New /INCLUDE style:/INCLUDEQRPGLESRC,xtools
Aside from SQL's ignoring /INCLUDE, it functions exactly like
/COPY. In fact,there's no reason to continue to use /COPY at all
unless you need the copiedsource to be used by the SQL
preprocessor. But even in that case, you can embed
a nested /INCLUDE in a source member that is /COPYed into
another source member.The SQL preprocessor sees and processes the
/COPY while it ignores the nested/INCLUDE.
As a side note, both /COPY and /INCLUDE allow you to store and
include sourcecode on the IFS and /COPY it into your compiled RPG
IV source. Simply specifythe IFS file (including the full path
name) enclosed in quotes on the /INCLUDEstatement as
follows:/INCLUDE"/xtools/include/rpgxtools.rpgle"
The quotes are actually double quotes, not the traditional
CL-styleapostrophes that you're used to using.
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7/27/2019 Tips and Techniques Dealing With COPY and Embedded
SQL
2/2
Bob Cozzi is a programmer/consultant,writer/author, and software
developer of the RPG xTools, a popularadd-on subprocedure library
for RPG IV. His book The Modern RPGLanguage has been the most
widely used RPG programmingbook for nearly two decades. He, along
with others, speaks at and runs thehighly-popular RPGWorld
conference for RPG
programmers.
MC Press Online
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October, 2008, 00:18
