feat(r): Add transmute() implementation

[paleolimbot]

This needs some extensive testing but is very cool! The overhead here is very low (we can execute x + 1 just as fast as native R data frames!).

library(sedonadb)

df <- data.frame(x = 1:1e6)

df |> sedonadb:::sd_transmute(y = x + 1)
#> ┌─────────┐
#> │    y    │
#> │ float64 │
#> ╞═════════╡
#> │     2.0 │
#> ├╌╌╌╌╌╌╌╌╌┤
#> │     3.0 │
#> ├╌╌╌╌╌╌╌╌╌┤
#> │     4.0 │
#> ├╌╌╌╌╌╌╌╌╌┤
#> │     5.0 │
#> ├╌╌╌╌╌╌╌╌╌┤
#> │     6.0 │
#> ├╌╌╌╌╌╌╌╌╌┤
#> │     7.0 │
#> └─────────┘
#> Preview of up to 6 row(s)
df |> sedonadb:::sd_transmute(y = sum(x))
#> ┌──────────────┐
#> │       y      │
#> │     int64    │
#> ╞══════════════╡
#> │ 500000500000 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ 500000500000 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ 500000500000 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ 500000500000 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ 500000500000 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ 500000500000 │
#> └──────────────┘
#> Preview of up to 6 row(s)
df |> sedonadb:::sd_transmute(y = sum(x + 1) + x)
#> ┌────────────────┐
#> │        y       │
#> │     float64    │
#> ╞════════════════╡
#> │ 500001500001.0 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ 500001500002.0 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ 500001500003.0 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ 500001500004.0 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ 500001500005.0 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ 500001500006.0 │
#> └────────────────┘
#> Preview of up to 6 row(s)

bench::mark(
  sd = df |> 
    sedonadb:::sd_transmute(y = sum(x + 1)) |> 
    sd_collect(),
  arrow = df |> 
    arrow::as_arrow_table() |> 
    dplyr::transmute(y = x + 1) |> 
    dplyr::collect(),
  duckdb = df |> 
    arrow::as_arrow_table() |> 
    dplyr::transmute(y = x + 1) |> 
    dplyr::collect(),
  dplyr = df |> dplyr::transmute(y = x + 1),
  check = FALSE
)
#> # A tibble: 4 × 6
#>   expression      min   median `itr/sec` mem_alloc `gc/sec`
#>   <bch:expr> <bch:tm> <bch:tm>     <dbl> <bch:byt>    <dbl>
#> 1 sd           1.25ms   2.77ms      334.     7.7MB     84.5
#> 2 arrow        9.09ms    9.8ms      100.   38.01MB     17.1
#> 3 duckdb       9.19ms   9.64ms      103.  145.85KB     16.4
#> 4 dplyr        1.27ms   1.37ms      697.    8.89MB    161.

^{Created on 2026-01-08 with reprex v2.1.1}