Re: Fix missing FORMAT when deparsing JSON_ARRAY(query)

[Richard Guo]

On Wed, Jul 22, 2026 at 3:22 PM Chao Li <li.evan.c...@gmail.com> wrote:
> Currently, JsonConstructorExpr does not store the JsonFormat information. To 
> fix this problem, we need to add a JsonFormat field to JsonConstructorExpr. 
> Please see the attached patch for details.

I considered recovering the format from func, as the arg that carries
the format lives there.  However, reaching it requires walking a
complex CoalesceExpr tree to find the JsonValueExpr, which seems too
fragile.

So, recording the input FORMAT in JsonConstructorExpr for deparsing
seems like the most feasible approach.

Regarding the patch, I don't think we need to handle format in
expression_tree_mutator/walker.  I also don't think we need to
copyObject the format.  Other than that, the patch LGTM.

I plan to push the attached patch soon barring any objections.

- Richard

v2-0001-Fix-deparsing-of-JSON_ARRAY-subquery-with-a-FORMA.patch
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