Re: Db2dclgn Indicator variables

LX-i<lxi0007@xxxxxxxxxxxx> 01/21/07 2:50 PM >>>
Frank Swarbrick wrote:
I'd also love to see some kind of COBOL support for "null" values. Even
with the proposed COBOL 2008 features (of which ANY LENGTH PREFIXED is
one)
I don't think there's anyway way to specify a field (other than an
actual
pointer, of course), as having a value of "NULL". But I'd love to see
it!
I know that C# has support for this. Never seen any other language with
it,
though.

VB handles nulls, as does Java.

I'm not sure it's quite as elegant as the C# method. Let me give a few
examples. I have a Java JDBC program that reads records from an Oracle
table and inserts them into a DB2 table with the same structure. Here is
some code from it:

resultset =
stmtOracle.executeQuery(SELECT_ORACLE_ICM_POSPAY_ISSUED_CHECKS);
while (resultset.next()) {
handleRow(++cnt, resultset, pstmtDB2);
pstmtDB2.executeUpdate();
if (++cnt2 > 5000) {
conICMDB2.commit();
cnt2 = 0;
}
}

The significant part of it is handleRow() (see below), which gets the
columns from the current row in the Oracle resultset and sets the
corresponding in the DB2 prepared-statement object. With the code for most
of the columns deleted, here's my Java:

void handleRow(int c, ResultSet rs, PreparedStatement ps)
throws SQLException {
int i = 0;

rba = rs.getInt("UNIQRBACNT");
ps.setInt(++i, rba);

lockedUserProfileID = rs.getInt("LOCKED_USER_PROFILE_ID");
if (rs.wasNull())
ps.setNull(++i, Types.INTEGER);
else
ps.setInt(++i, lockedUserProfileID);
}

UNIQRBACNT is a columns defined as NOT NULL, while LOCKED_USER_PROFILE_ID is
nullable. Look at how much extra code is required to handle the nullable
column? In fact, the non-nullable one can simply be:
ps.setInt(++i, rs.getInt("UNIQRBACNT"));

In C# there is a way to declare a field as being "nullable". That is,
instead of say...

int lockedUserProfileID;

You instead say

int? lockedUserProfileID;

Then, and I haven't actually tested it so I may in fact be wrong, I imagine
you would be able to say something like:
lockedUserProfileID = rs.getInt("LOCKED_USER_PROFILE_ID");
ps.setInt(++i, lockedUserProfileID);

without the annoying testing for null.

To be honest, as I write this I am not convinced that this would actually
work. But it certainly would be nice if it did. If I think of it I will
indeed test this at home.

Anyway, check out this website for more info:
http://blogs.msdn.com/ericgu/archive/2004/05/27/143221.aspx

Does Java, in fact, support something like this? I couldn't find anything,
but I am far from expert.

Frank

---
Frank Swarbrick
Senior Developer/Analyst - Mainframe Applications
FirstBank Data Corporation - Lakewood, CO USA
.

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