On Jan 18, 2011, at 8:28 PM, David Balažic wrote:
> So, does that testcase really work on Oracle?
Yes. Now revisiting the tests, we are cheating to make the generic mapping work
with Oracle. The reason for this is Oracle driver's insistence on circumventing
basic JDBC abstractions. We take a generic mapping [1] and alter the procedure
object in the test code [2]. Notice how we install Oracle-specific type as an
OUT parameter type:
// the type used below is "oracle.jdbc.OracleTypes.CURSOR"
proc.addCallParameter(new ProcedureParameter("result",
OracleAdapter.getOracleCursorType(), ProcedureParameter.OUT_PARAMETER));
For now the above (creating or tweaking procedure mapping metadata in the code)
is one possible way for dealing with Oracle. Going forward, we may either
support numeric values for column types (so that a user could map this column
as "-10", same as "oracle.jdbc.driver.OracleTypes.CURSOR"). Or maybe we should
dynamically rewrite Cayenne-mapped stored procedures, adding CURSOR parameter
inside Cayenne (not yet sure how what part of the mapping should trigger such
behavior).\
And unfortunately there's little hope that after all these years Oracle will
finally fix their driver (or at least implement ParameterMetaData JDBC
interface so that Oracle-specific types could be used dynamically).
Andrus
[1]
<procedure name="cayenne_tst_select_proc">
<procedure-parameter name="aName" type="VARCHAR" length="254" direction="in"/>
<procedure-parameter name="paintingPrice" type="INTEGER" direction="in"/>
</procedure>
[2] OracleStackAdapter.java:
public void tweakProcedure(Procedure proc) {
if
(DataContextProcedureQueryTest.SELECT_STORED_PROCEDURE.equals(proc.getName())
&& proc.getCallParameters().size() == 2) {
List params = new ArrayList(proc.getCallParameters());
proc.clearCallParameters();
proc.addCallParameter(new ProcedureParameter("result", OracleAdapter
.getOracleCursorType(), ProcedureParameter.OUT_PARAMETER));
Iterator it = params.iterator();
while (it.hasNext()) {
ProcedureParameter param = (ProcedureParameter) it.next();
proc.addCallParameter(param);
}
proc.setReturningValue(true);
}
}
