Subquery ORDER BY and LIMIT not working in knex (postgres) - postgresql

Question

I have the following query:
// Need a subquery to limit to 1 update
const subQuery = queryBuilder => queryBuilder
.forUpdate()
.where('won', false)
.where('win_after', '<=', knex.fn.now())
.orderBy('priority', 'desc')
.limit(1);
knex('prizes')
.forUpdate()
.where(subQuery)
.update({
won_at: knex.fn.now(),
won: true,
})
.returning('*');
The query I'm trying to buid is
UPDATE
"prizes"
SET
"won_at" = CURRENT_TIMESTAMP,
"won" = $1
WHERE
(
SELECT * FROM "prizes"
WHERE "won" = $2
AND "win_after" <= CURRENT_TIMESTAMP
ORDER BY "priority"
LIMIT 1
)
returning *
I'm trying to find one prize (only 1) to update and mark as one (sorting by prize priority).
The generated query is
update "prizes" set "won_at" = CURRENT_TIMESTAMP, "won" = $1 where ("won" = $2 and "win_after" <= CURRENT_TIMESTAMP) returning * trx4
(See this knex playground link)
So it's missing the ORDER BY and LIMIT. Still a novice with knex and pg, so any help is appreciated!

Answer 1

Initially I was tring to implement CTEs (Common Table Expressions) but after all I managed to do without:
// Need a subquery to limit to 1 update
const subQuery = db<Prize>('prizes')
.select('uuid')
.forUpdate()
.whereNot('won', true)
.where('win_after', '<=', db.fn.now())
.orderBy('priority', 'desc')
.first()
return db<Prize>('prizes')
.transacting(trx)
.where('uuid', subQuery)
.update({
won_at: db.fn.now(),
won: true,
})
.returning('*');
});
Which translates to the following SQL:
update
"prizes"
set
"won_at" = CURRENT_TIMESTAMP,
"won" = true
where
"uuid" = (
select
"uuid"
from
"prizes"
where
not "won" = true
and "win_after" <= CURRENT_TIMESTAMP
order by
"priority" desc
limit
1 for
update
) returning *
Here is the knex playground.