# Importing external targets with evidence

WFC 2.0 imports targets from a finalized CSV or Excel table and a companion DCF evidence record. It does not construct a production target from an unexplained runtime table.

    dims <- wf_dims(
      age_group = c("18-34", "35-54", "55+"),
      region = c("north", "south")
    )

    wf_target_template("population-margins.csv", dims)

Complete the companion `population-margins.csv.source.dcf` with publisher, dataset title, citation, reference period, population scope, retrieval date, license, transformation, selection timing, demo status, and the final SHA-256.

    target <- wf_import_target(
      "population-margins.csv",
      "population-margins.csv.source.dcf",
      dims,
      key_map = c(age_group = "age_group", region = "region"),
      count = "population_count",
      production = TRUE
    )

For joint-cell post-stratification, the imported population table must contain the required joint combinations. For an independent reference sample, use `wf_import_reference()` with its own evidence file.

The checksum proves that the imported data match the evidence record. It does not prove that the publisher, transformation, or scientific choice is valid; those remain review questions.