feat(r/sedonadb): Add join expression evaluation

[paleolimbot]

Adds sd_join() to the R bindings with friendly specification of the join condition and the output selection. These are both a huge pain and are very verbose to deal with...there are a lot of ways to specify join keys and a lot of ways to deal with disambiguating names on the output. I implemented roughly how this is done in dplyr with join_by() and suffix with an escape hatch for other types of selections one might want to do.

library(sedonadb)
library(nycflights13)

res <- nycflights13::flights |> 
  sd_select(year, month, day, flight, tailnum) |> 
  sd_join(
    nycflights13::planes |> sd_select(tailnum, type, manufacturer),
    select = sd_join_select_default()
  ) |> 
  sd_group_by(manufacturer) |> 
  sd_summarise(n = n()) |> 
  sd_arrange(desc(n))

res
#> <sedonab_dataframe: NA x 2>
#> ┌───────────────────────────────┬───────┐
#> │          manufacturer         ┆   n   │
#> │              utf8             ┆ int64 │
#> ╞═══════════════════════════════╪═══════╡
#> │ BOEING                        ┆ 82912 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌┤
#> │ EMBRAER                       ┆ 66068 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌┤
#> │ AIRBUS                        ┆ 47302 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌┤
#> │ AIRBUS INDUSTRIE              ┆ 40891 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌┤
#> │ BOMBARDIER INC                ┆ 28272 │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌┤
#> │ MCDONNELL DOUGLAS AIRCRAFT CO ┆  8932 │
#> └───────────────────────────────┴───────┘
#> Preview of up to 6 row(s)

bench::mark(as.data.frame(res))
#> # A tibble: 1 × 6
#>   expression              min   median `itr/sec` mem_alloc `gc/sec`
#>   <bch:expr>         <bch:tm> <bch:tm>     <dbl> <bch:byt>    <dbl>
#> 1 as.data.frame(res)   2.75ms   3.13ms      307.    31.8KB        0

bench::mark(
res <- nycflights13::flights |> 
  dplyr::select(year, month, day, flight, tailnum) |> 
  dplyr::inner_join(
    nycflights13::planes |> dplyr::select(tailnum, type, manufacturer),
    by = "tailnum"
  ) |> 
  dplyr::count(manufacturer) |> 
  dplyr::arrange(desc(n))
)
#> # A tibble: 1 × 6
#>   expression                             min median `itr/sec` mem_alloc `gc/sec`
#>   <bch:expr>                          <bch:> <bch:>     <dbl> <bch:byt>    <dbl>
#> 1 res <- dplyr::arrange(dplyr::count… 17.2ms 18.8ms      47.1      44MB     101.

res
#> # A tibble: 35 × 2
#>    manufacturer                      n
#>    <chr>                         <int>
#>  1 BOEING                        82912
#>  2 EMBRAER                       66068
#>  3 AIRBUS                        47302
#>  4 AIRBUS INDUSTRIE              40891
#>  5 BOMBARDIER INC                28272
#>  6 MCDONNELL DOUGLAS AIRCRAFT CO  8932
#>  7 MCDONNELL DOUGLAS              3998
#>  8 CANADAIR                       1594
#>  9 MCDONNELL DOUGLAS CORPORATION  1259
#> 10 CESSNA                          658
#> # ℹ 25 more rows

This also works with st_intersects() and friends for a spatial join:

library(sedonadb)

cities <- sd_read_parquet(
  "https://raw.githubusercontent.com/geoarrow/geoarrow-data/v0.2.0/natural-earth/files/natural-earth_cities.parquet"
)

countries <- sd_read_parquet(
  "https://raw.githubusercontent.com/geoarrow/geoarrow-data/v0.2.0/natural-earth/files/natural-earth_countries.parquet"
)

countries |> 
  sd_join(
    cities,
    by = sd_join_by(st_intersects(x$geometry, y$geometry)),
    select = sd_join_select(
      city = y$name,
      country = x$name,
      continent,
      geometry = y$geometry
    )
  )
#> <sedonab_dataframe: NA x 4>
#> ┌──────────────┬────────────────┬───────────┬───────────────────────────────┐
#> │     city     ┆     country    ┆ continent ┆            geometry           │
#> │     utf8     ┆      utf8      ┆    utf8   ┆            geometry           │
#> ╞══════════════╪════════════════╪═══════════╪═══════════════════════════════╡
#> │ Vatican City ┆ Italy          ┆ Europe    ┆ POINT(12.4533865 41.9032822)  │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ San Marino   ┆ Italy          ┆ Europe    ┆ POINT(12.4417702 43.9360958)  │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ Vaduz        ┆ Austria        ┆ Europe    ┆ POINT(9.5166695 47.1337238)   │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ Lobamba      ┆ eSwatini       ┆ Africa    ┆ POINT(31.1999971 -26.4666675) │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ Luxembourg   ┆ Luxembourg     ┆ Europe    ┆ POINT(6.1300028 49.6116604)   │
#> ├╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
#> │ Bir Lehlou   ┆ Western Sahara ┆ Africa    ┆ POINT(-9.6525222 26.1191667)  │
#> └──────────────┴────────────────┴───────────┴───────────────────────────────┘
#> Preview of up to 6 row(s)

^{Created on 2026-04-24 with reprex v2.1.1}

[Copilot]

Pull request overview

Adds join-expression support to the R sedonadb bindings, enabling sd_join() with dplyr-like join condition specification (sd_join_by()) and post-join column selection/disambiguation (sd_join_select_default(), sd_join_select()), backed by new Rust FFI methods for join execution and expression introspection.

Changes:

• Introduces sd_join(), sd_join_by(), sd_join_select_default(), and sd_join_select() plus join expression evaluation utilities.
• Extends Rust/R FFI to support DataFusion join_on() and adds expression inspection helpers (qualified_name(), variant_name(), parse_binary()).
• Adds comprehensive testthat coverage and snapshots for join-expression behavior and default selection rules.

Reviewed changes

Copilot reviewed 21 out of 22 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
r/sedonadb/R/join-expression.R	New join condition/select specification and join-expression evaluation + default post-join projection logic.
r/sedonadb/R/dataframe.R	Adds sd_join() and extends sd_summarise()/sd_summarize() with .env.
r/sedonadb/R/expression.R	Adds sd_expr_parse_binary() and makes expression masks drop duplicate column names.
r/sedonadb/R/000-wrappers.R	Adds generated R wrappers for InternalDataFrame$join() and new SedonaDBExpr inspection methods.
r/sedonadb/src/rust/src/dataframe.rs	Adds InternalDataFrame::join() using DataFusion join_on() with aliases and parsed JoinType.
r/sedonadb/src/rust/src/expression.rs	Exposes qualified_name(), variant_name(), and parse_binary() over FFI for R-side logic.
r/sedonadb/src/rust/api.h	Declares new FFI symbols for join and expression inspection.
r/sedonadb/src/init.c	Registers new .Call entry points for join + expression inspection.
r/sedonadb/NAMESPACE	Exports new join APIs and S3 methods for printing and $ table refs.
r/sedonadb/tests/testthat/test-join-expression.R	New test suite for join-by/select evaluation, ambiguity errors, and default projection behavior.
r/sedonadb/tests/testthat/_snaps/join-expression.md	Snapshot outputs for join-expression printing and evaluated expressions.
r/sedonadb/tests/testthat/test-dataframe.R	Adds an integration-style test ensuring select behavior is applied to join results.
r/sedonadb/tests/testthat/test-expression.R	Adds tests for new expression inspection helpers.
r/sedonadb/man/sd_join.Rd	New user-facing docs for sd_join().
r/sedonadb/man/sd_join_by.Rd	New user-facing docs for sd_join_by().
r/sedonadb/man/sd_join_select.Rd	New user-facing docs for sd_join_select().
r/sedonadb/man/sd_join_select_default.Rd	New user-facing docs for sd_join_select_default().
r/sedonadb/man/sd_expr_column.Rd	Adds alias/doc entry for sd_expr_parse_binary().
r/sedonadb/man/sd_summarise.Rd	Documents new .env parameter for sd_summarise()/sd_summarize().
r/sedonadb/.Rbuildignore	Ignores local AI assistant marker files.
.pre-commit-config.yaml	Excludes testthat snapshot directory from trailing-whitespace hook.
.gitignore	Ignores .positai.

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Pull request overview

Copilot reviewed 22 out of 23 changed files in this pull request and generated 3 comments.

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[paleolimbot]

If there are no objections I'll merge this sometime tomorrow!