Set the Rducks execution plan for a connection — rducks_set_execution

Stores the R-side default execution plan used by subsequent rducks_register_scalar_udf() calls through this connection and updates the native runtime backend needed by that plan. Scalar-UDF registration still defines Rducks evaluation semantics such as scalar row calls versus vectorized chunk calls, declared types, NULL handling, error handling, and side effects. The selected evaluator/marshalling for an already-registered scalar UDF remains frozen in its database-catalog metadata.

Usage

rducks_set_execution_plan(
  con,
  plan = rducks_execution_plan(),
  threads = NULL,
  external_threads = NULL
)

Arguments

con: A duckdb_connection already enabled with rducks_enable().
plan: An rducks_execution_plan() object.
threads: Optional positive integer to set with PRAGMA threads.
external_threads: Optional positive integer to set with SET external_threads. Use NULL to restore/keep the previous setting after Rducks briefly forces single-thread SQL execution to update its native backend on the recorded main R thread. For actual DuckDB worker concurrency, keep this smaller than threads.

Value

con, invisibly.

Examples

# \donttest{
db <- duckdb::dbConnect(duckdb::duckdb(config = list(allow_unsigned_extensions = "true")))
rducks_enable(db)
rducks_set_execution_plan(db, rducks_execution_plan("arrow_c", "serial"))
rducks_release(db)
DBI::dbDisconnect(db)
# }