schema.md
In alekrutkowski/autoschema: Simple diagram of relationships between data.frames

`schema`

Prepare a schema diagram of relations between data.frames and/or csv/tsv files

This function uses the column names and column types/classes of data.frames and/or csv files to produce a schema diagram of relations between these tables. By default, "correct" relations (same column names and same types/classes) are drawn as solid black lines. If there are evident type/class mismatches despite the same column names, the relation is drawn as a striped red line. If there is a slight mismatch that can be overcome by automatic coercion (integer-double, but both columns numeric) the relation line is dashed but black. list() list() At least one data.frame or csv/tsv file needs to be specified. In other words, either data_frames or data_frame_names or csv_files parameter needs to be specified. It is allowed to use all the three arguments/parameters simultaneously i.e. have some data.frames provided directly (as values), some others indirectly (as object names) and yet some others as csv/tsv file names/paths/urls to be imported via fread .

schema(
  data_frames = list(),
  data_frame_names = character(0),
  csv_files = character(0),
  output_type = "grViz",
  all_links = FALSE
)

Argument |Description ------------- |---------------- data_frames | A list of data.frames. data_frame_names | A character vector of names of data.frame objects. csv_files | A character vector of file names, file paths, or urls pointing to csv/tsv files. This value is passed to fread 's argument/parameter input . output_type | A string -- one of the three options: "grViz" (default) or "gv" or "svg" . See the return value description below. all_links | Logical (Boolean) -- if FALSE (default) all linkages between the data.frames are included in a graph (as edges); if TRUE only the minimum necessary linkages (edges) are included and some linkages can be inferred indirectly as passing through "intermediary" data.frames.

One of the three possibilities:

if output_type is "grViz" : a diagram plot produced by grViz (object of class htmlwidget )
if output_type is "gv" : a string (character vector of length 1) with the GraphViz code (which can be later edited for tweaks)
if output_type is "svg" : a string (character vector of length 1) with the svg (xml) code produced by export_svg