How to filter a GROQ query based on the presence of a specific field in the schema.

I have this groq query where I query all the pages and posts.

I only want the posts which

publishedAt < now

. However, the

page

type doesn’t have the

publishedAt

field. If I add that condition, I will get no

page

How could I only apply the filter if the doc has publishedAt?

Could you not extend the third condition to be

type

= page OR

publishedAt < now

?
Something like

I think it works, why can’t we use

_type == 'post' && dateTime(publishedAt) < dateTime(now())

Or is any way to express “only apply the condition when there is a publishedAt in the schema”

I’m using API version “v2021-10-21”

I don't know if there's a way to express "only apply the condition when there's a publishedAt in the schema" but there is the

defined()

property which returns

true

if the argument is non-

null

, otherwise

false

.
So you could write the third condition as something like:

There might be a better way.. but that's what I can think of

Great suggestions, (Removed Name)! Off to a running start! ✨

There are several different ways you could approach this. I like (Removed Name)’s approach because it keeps things very readable and easy to parse—and yours (using

_type == 'post' &&

instead of

_type == 'page' ||

) should work just as well. The reason this may not be working for you is because in the examples above, the filter isn’t ended before the projection (

{ … }

), so be sure to correct for that if needed.
Another option is to use one of GROQ’s functions to test for

publishedAt

, which removes the need for the second

_type

check. The

select

and

coalesce

functions are two possibilities, and both rely on the fact that a GROQ query’s filter essentially boils down to

true

or

false

. We could use `select`:

This function works much like a conditional, where we test if

publishedAt

is not null, and if it’s not, we return

dateTime(publishedAt) < dateTime(now())

to the filter to be executed. If

publishedAt

is null, which you say will be the case for all

page

documents, then we just return

true

so that it doesn’t impact the filter.
Perhaps a bit more concise is `coalesce`:


This function returns the first non-null value. Thankfully, GROQ will resolve

dateTime(null)

to

null

, and when that’s compared against

dateTime(now())

, it returns null. Like in the

select

example, this will return

true | false

if

publishedAt

is non-null, or

true

if it is null.
I might have something wrong here, but hopefully it can get you started.

Thank you both for the answers 🎉 You made my day