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Utility functions for visualization specifications

spec_utility.Rd

These functions allow you to extract various information from a Spec object returned by ggsql_execute().

Usage

ggsql_metadata(spec)

ggsql_sql(spec)

ggsql_visual(spec)

ggsql_layer_count(spec)

ggsql_layer_data(spec, index = 1L)

ggsql_stat_data(spec, index = 1L)

ggsql_layer_sql(spec, index = 1L)

ggsql_stat_sql(spec, index = 1L)

ggsql_warnings(spec)

Arguments

spec

A Spec object as returned by ggsql_execute()

index

Layer index

Value

  • ggsql_metadata: A list with elements rows, columns, and layer_count

  • ggsql_sql: A character string with the SQL portion of the query

  • ggsql_visual: A character string with the visual portion of the query

  • ggsql_layer_count: An integer giving the number of layers

  • ggsql_layer_data: A data frame, or NULL if no data is available for this layer

  • ggsql_stat_data: A data frame, or NULL if the layer doesn't use a stat transform

  • ggsql_layer_sql: A character string with the SQL query used by the layer to fetch its data, or NULL if the layer doesn't have any data.

  • ggsql_stat_sql: A character string with the SQL query used by the layers stat transform, or NULL if the layer doesn't have a stat transform.

  • ggsql_warnings: A data.frame with columns message, line, and column giving the validation warnings for the spec

Examples

reader <- duckdb_reader()
ggsql_register(reader, mtcars, "cars")
spec <- ggsql_execute(reader,
  "SELECT * FROM cars VISUALISE mpg AS x DRAW histogram"
)

ggsql_metadata(spec)
#> $rows
#> [1] 17
#> 
#> $columns
#> [1] "stroke"  "pos1"    "pos1end" "opacity" "pos2"    "fill"    "pos2end"
#> 
#> $layer_count
#> [1] 1
#> 

ggsql_visual(spec)
#> [1] "VISUALISE mpg AS x DRAW histogram"