How to use native sql function with HQL query?

Question

I am trying to execute a query like the following, using HQL, that uses a native SQL function (dbms_lob.getlength):

def results = Attachment.execute         


        

Answer 1

In Attachment domain add new field Long fileBytesLength and inside mapping closure add the formula for calculating the length of fileBytes field.

class Attachment {

    String createUserName
    String originalFilename

    byte[] fileBytes
    Long fileBytesLength

    Date dateCreated
    //Other Properties

    static mapping = {
        //Other mappings
        fileLength formula: "dbms_lob.getlength(fileBytes)"
    }
}

And then modify the query to:

def results = Attachment.executeQuery(
    'select id, originalFilename, fileBytesLength, dateCreated, createUserName '+
    'from Attachment a where a.id not in '+
         '(select attachmentId from SpecVersion sv where sv.attachmentId is not null) '+
    'and a.dateCreated > sysdate - 30')