You will see how the parameter $conds is converted to SQL conditions in eZPersistentObject::conditionTextByRow, but you probably found that yourself ;-) But it doesn't support OR that way.
You'll have to use the last parameter, $custom_conds, which has to be a string of SQL conditions ready to be inserted inside the full SQL query.
The last parameter in my version (ez 3.8.4) is $custom_fields which allows for operations on fields (like count or sum). I don't see a way to use this for an OR condition. Could you give me an example for what you mean?
It seems like this parameter was added on the trunk (it will be in 3.9), but only to the fetchObjectList function. Because fetchObject calls fetchObjectList, the parameter can be easily added to fetchObject too. Maybe you can post an enhancement request for this?
Thanks for the answer. I suppose I will just add the option to add custom SQL to my copy of eZPersistentObject::fetchObjectList and eZPersistentObject::fetchObject. As the parameters are optional this should not have any negative effect on any code that makes use of these functions.
Enhancement request is posted http://issues.ez.no/IssueView.php?Id=9767
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