Lineage edges as a data frame

Flattens a lineage object's column-level edges into one row per edge, for filtering, joining, and summarising with ordinary data frame tools. For edges produced by extract_lineage(), the transformation column classifies each edge ("identity" for plain column passthrough, "aggregation", or "transformation") and expression records the output column's defining expression; both are NA for hand-built edges. With include_indirect = TRUE, indirect edges are classified by how the source column is used — "filter", "join", "group_by", or "sort" — with NA for expression.

Usage

lineage_edges(lineage)

Arguments

lineage

The result of extract_lineage(), or any list with nodes and edges built with create_table_node() and create_column_edge().

Value

A data frame with columns source_table, source_column, target_table, target_column, transformation, and expression.

See also

Other lineage accessors: lineage_diff(), lineage_tables(), lineage_upstream()

Examples

lineage <- list(
  nodes = list(
    create_table_node("orders", c("order_id", "amount")),
    create_table_node("daily_totals", "total", table_type = "target")
  ),
  edges = list(
    create_column_edge("orders", "amount", "daily_totals", "total")
  )
)
lineage_edges(lineage)
#>   source_table source_column target_table target_column transformation
#> 1       orders        amount daily_totals         total           <NA>
#>   expression
#> 1       <NA>