Can I select null as a column value in HQL query?

Question

I need a list with three columns. column 1st and 3rd having values while 2nd as null. Can I do it through HQL query?

I need something like this:

select id, null, name from MyClass

Where MyClass as well as underlying table has only two properties/columns ie, "id" and "name"

Answer 1

You can use nullif() function to generate null.

It accepts two arguments. If arguments are equal, it'll return null value.

Answer 2

Another option that seems to work (tested on DB2, MySQL, Oracle, and SQL Server):

select id, cast(null as char), name from ...

You could subclass the Hibernate dialect and abstract it with a custom function:

registerFunction("always_null", 
  new SQLFunctionTemplate(Hibernate.STRING, "cast(null as char)"));

and then use this in your HQL:

select id, always_null(), name from ...