Hi, I am trying to run the following HQL through Hibernate:

"select distinct col1, null as col2, col3 from table1"

However, this throws the error:
unexpected AST node: NULL

Is there some way to always get back NULL for a column?

Thanks for any help!

have you tried just ...

Yep, thats even worse... it returns data that isn't correct.


If I have a table with 1 row, 3 cols:

COL1 | COL2 | COL3
----------------------
'val1' | 'val2' | 'val3'


And I run:
"select COL1, NULL, COL3 from TABLE1"

What I want to get back is: Object[3]{"val1", null, "val3"}

But what I get is: Object[1]{"val1"}

Likewise, if I said "select COL1, COL2, NULL from TABLE1"
I get back: Object[2]{"val1", val2"}

Hibernate seems to just stop processing columns once it hits a NULL in the statement, which is why I was going to try to alias them instead. Interestingly, the above does not throw an error, even though it seems like it should.

oh, it might also be worth mentioning that if I do:
"select COL1, 'foo' as COL2, COL3 from TABLE1"

Then I do get back: Object[3]{"val1", "foo", "val3"}

Also, if I try:
"select COL1, NonExistantCOL, COL3 from TABLE1"

Then it does throw an exception saying it cant find 'NonExistantCOL'. So it does seem to properly parse the NULL as something and tries to run.

Maybe I'll start debugging into the Hibernate code and see if I can find anything else...

The plot thickens... From my debugging I've found that in SessionImpl.list() it calls getHQLQueryPlan() to get a new instance of an HQLQueryPlan for the statement.

If I pass in my "select col1, null, col3 from table1" hql string to SessionImpl.list(), that gets passed into the HQLQueryPlan, and it puts together a plan for the query "select col1, col3 from table1" (as the actual SQL query). So it isn't parsing the query correctly.

Then, at some point further in, it also incorrectly processes the ResultSet, and only grabs the first column to return in an Object[1]{val1}

So it looks like I'm fighting multiple bugs here. First it takes my 3 column HQL query, turns it into a 2 column SQL query, then takes my 2 column ResultSet and turns it into a 1 column Object[].

Has no one ever done this before?