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Define a data lineage graph

Source: R/lineage.R
define_lineage.Rd

define_lineage() collects lineage edges into an auditable graph that can be queried with trace_dependencies() and used by assess_impact(). The graph is stored as a tidy edge list plus a node table; no external graph library is required, although as_igraph() is provided for users who prefer one.

Usage

define_lineage(
  ...,
  edges = NULL,
  nodes = NULL,
  dataset = NULL,
  variable = NULL,
  downstream = NULL,
  relationship = "derives"
)

Arguments

...

One or more edge tibbles created by lineage_edge(), or a single data frame of edges.

edges

Optional data frame of edges with columns from, to and optionally from_type, to_type, relationship, condition.

nodes

Optional node table with columns node and type, used to override inferred types and to attach labels.

dataset, variable, downstream

Convenience arguments matching the common workflow: declare that downstream objects depend on dataset.variable.

relationship

Relationship used with the convenience arguments.

Value

An object of class td_lineage.

Examples

lineage <- define_lineage(
  lineage_edge("ADSL.TRT01P", "ADLB.TRT01P", relationship = "derives"),
  lineage_edge("ADLB.AVAL", "MMRM", relationship = "models"),
  lineage_edge("MMRM", "Table_14_2_1", relationship = "reports")
)
trace_dependencies(lineage, from = "ADSL.TRT01P")
#> # A tibble: 1 × 5
#>   node        node_type depth path                       edge_relationship
#>   <chr>       <chr>     <int> <chr>                      <chr>            
#> 1 ADLB.TRT01P variable      1 ADSL.TRT01P -> ADLB.TRT01P derives