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https://issues.apache.org/jira/browse/ARROW-5718?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16872287#comment-16872287
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Romain François commented on ARROW-5718:
----------------------------------------
I think it's fine if we were to auto splice, i.e.:
{code:r}
record_batch(mtcars)
{code}
would be the same as
{code:r}
record_batch(!!!mtcars)
{code}
because unnamed, this is the direction we'll take in. dplyr too for e.g.
summarise and mutate.
However, something like :
{code:r}
record_batch(x = mtcars)
{code}
will create a struct array, aka a data frame column.
> [R] Add as_record_batch()
> -------------------------
>
> Key: ARROW-5718
> URL: https://issues.apache.org/jira/browse/ARROW-5718
> Project: Apache Arrow
> Issue Type: Improvement
> Components: R
> Reporter: Neal Richardson
> Priority: Minor
> Fix For: 0.14.0
>
>
> ARROW-3814 /
> [https://github.com/apache/arrow/pull/3565/files#diff-95ad459e0128bfecf0d72ebd6d6ee8aaR94]
> changed the API of `record_batch()` and `arrow::table()` such that you could
> no longer pass in a data.frame to the function, not without [massaging it
> yourself|https://github.com/apache/arrow/pull/3565/files#diff-09c05d1a6ff41bed094fbccfa76395a6R27].
> That broke sparklyr integration tests with an opaque `cannot infer type from
> data` error, and it's unfortunate that there's no longer a direct way to go
> from a data.frame to a record batch, which sounds like a common need.
> In order to follow best practices (cf. the
> [tibble|https://tibble.tidyverse.org/] package, for example), we should (1)
> add an {{as_record_batch}} function, which the data.frame method is probably
> just {{as_record_batch.data.frame <- function(x) record_batch(!!!x)}}; and
> (2) if a user supplies a single, unnamed data.frame as the argument to
> {{record_batch()}}, raise an error that says to use {{as_record_batch()}}. We
> may later decide that we should automatically call as_record_batch(), but in
> case that is too magical and prevents some legitimate use case, let's hold
> off for now. It's easier to add magic than remove it.
> Once this function exists, sparklyr tests can try to use {{as_record_batch}},
> and if that function doesn't exist, fall back to {{record_batch}} (because
> that means it has an older released version of arrow that doesn't have
> as_record_batch, so record_batch(df) should work).
> cc [~javierluraschi]
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