SomeClass.sqlpassthrough('SqlExpression',Type1OfTupleResult,Type2OfTupleResult,...)

Example of how the OCL looks like to call a stored procedure:

Anvandare.sqlpassthrough('sp_Upd_Losen ' + self.AnvId.asString + ', \'' + self.Anvandarnamn + '\', @aNyttLosenord', Int32)

Notes:

• @aNyttLosenord here is automatically available because it's a variable available when the function is called.
• You need to quote strings to be passed (if they aren't variables), like self.Anvandarnamn above. The \' is an escaped quote in OCL (Escape codes).

• Int32 at the end is the SQL server return code.
• Your expression starts with a class, not an object.

A use case and examples of using sqlPassThrough can be found here: "PSExpression, or how to do things in the DB from MDriven"

Note also that the sqlPassThrough can create tuples:

AccountPlan.SQLPassthrough('select somekey,sum(somestuff),sum(someotherstuff) from table1,2,3 where ...',String,Integer,Integer)->collect(xtuple|let xobject=SomeNewTransient.Create in (xobject.Key:=xtuple.Part1;xobject.SomeSum:=xtuple.Part2))

Also, look here: OCLOperators sqlpassthroughobjects