Add WHEN MATCHED THEN UPDATE clause — when_matched_update • deltaR

Specifies how to update target rows when they match source rows.

Usage

when_matched_update(builder, ...)

Arguments

builder: A DeltaMergeBuilder object.
...: Additional arguments passed to methods.

Value

The modified DeltaMergeBuilder (for method chaining).

Method arguments

The method for DeltaMergeBuilder accepts:

updates: Named character vector mapping target columns to source expressions. Names are target column names, values are SQL expressions (e.g., "source.column").
predicate: Optional character. Additional predicate to filter which matched rows should be updated.

Examples

if (FALSE) { # \dontrun{
# Update all matched rows
delta_merge(table, source, "target.id = source.id") |>
  when_matched_update(c(value = "source.value", name = "source.name"))

# Update only matched rows where a condition is met
delta_merge(table, source, "target.id = source.id") |>
  when_matched_update(
    c(value = "source.value"),
    predicate = "source.value > target.value"
  )
} # }