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coby 2021-03-25T16:52:01.033100Z
Hopefully this is the right place to ask this... I'm struggling with constraining a join across a one-to-many association:
(d/q '[:find (pull ?p [:post/slug
{:post/fields
[:field/key
:field/lang
:field/content]}])
:in $ ?slug ?lang
:where
[?p :post/slug ?slug]
[?p :post/fields ?field]
[?field :field/lang ?lang]]
db "child-page" :en):en, which is not what I want. I suspect this is because :post/fields is :db.cardinality/many and the join does not constrain them properly. Is this possible or do I need to filter fields after the fact?
Joe Lane 2021-03-25T16:59:40.035Z
You can perform a query + pull in that find clause. Try this:
(d/q '[:find ?slug (pull ?field
[:field/key
:field/lang
:field/content])
:in $ ?slug ?lang
:where
[?p :post/slug ?slug]
[?p :post/fields ?field]
[?field :field/lang ?lang]]
db "child-page" :en)Joe Lane 2021-03-25T16:59:47.035200Z
@ctamayo ^^
coby 2021-03-25T17:02:11.035900Z
That works! Thanks!
Joe Lane 2021-03-25T17:03:14.037Z
If you really want a map you could do:
(d/q '[:find ?slug ?key ?lang ?content
:in $ ?slug ?lang
:keys post/slug field/key field/lang field/content
:where
[?p :post/slug ?slug]
[?p :post/fields ?field]
[?field :field/key ?key]
[?field :field/lang ?lang]
[?field :field/content ?content]
db "child-page" :en)