Using Postgres' array types and operators

[google...@sql-workbench.net]

Hello,

is it possible to use Postgres' array types and operators in QueryDSL?

I'm looking for something to map the expression ARRAY[column_name]  and the array concatenation operator some_array||some_column to QueryDSL.

Specifically in the context of a common table expression:

with recursive category_tree as (
  select id, parent_id, sort_order, name, array[0,id] as sort_path, 0 as level
  from category
  where parent_id is null
  union all
  select c.id, c.parent_id, c.sort_order, c.name, p.sort_path||array[c.sort_order, c.id], p.level + 1
  from category c
    join category_tree p on c.parent_id = p.id
)
select *
from category_tree
order by sort_path;

How would I write a template (?) to support the array[0,id] and p.sort_path||array[c.sort_order, c.id] expressions?

I already have the rest, but I have no clue how to integrate something like that.

We have already written support for the array_agg() aggregate function, but this seems quite different.

[timowest]

Querydsl templates have fixed amounts of parameters, here are the variants for two parameters:

concat: {0} || {1}

array constructor: array[{0}, {1}]

[google...@sql-workbench.net]

How would I define such a template?

I don't really understand how the Java code for that would look like.