Building expression for complex key

Question

Hi
I have an object with a complex key. I'm trying to create an expression that will generate a select to retrieve a list of objects by the complex primary key.
The select should look like :
select *
from <table_name>
where (<col1>,<col2>) in ( (val1,val2) , (val1, val3) )
The problem is i cannot find a way to create the expression (<col1>,<col2>).
Can anyone give me an example on how this can be done ?
Thanks
Inbal

Answer 1

TopLink expressions do not currently support the IN((..), (..)), or nested array IN SQL. You will either need to generate your own custom SQL for this. Or build the expression dynamically using AND and OR instead of an IN.
i.e.
ExpressionBuilder builder = new ExpressionBuilder();
Expression inPrimaryKeys = null;
Iterator iterator = primaryKeys.iterator();
while (iterator.hasNext()) {
List primaryKey = (List) iterator.next();
inPrimaryKeys = builder.get("id1").equal(primaryKey.get(0)).
and(builder.get("id2").equal(primaryKey.get(1))).
or(inPrimaryKeys);