Lists every raw field, calculated field, and parameter that is defined in a datasource but referenced nowhere: not on any worksheet shelf, filter, or sort, not in any tooltip, not inside any other calculated-field formula, and not in any dashboard filter zone. When rebuilding a workbook in another tool, these are the fields that can safely be left behind.
Value
A tibble with columns:
- datasource
Datasource the field belongs to.
- field_type
"raw","calculated", or"parameter".- name
Human-readable field name / caption.
- tableau_internal_name
Bracketed internal Tableau name.
- datatype
Field data type.
- role
"measure"or"dimension".- is_hidden
Whether a raw field is hidden (
NAfor calculated fields and parameters).
Details
Matching is deliberately conservative: a field is reported as unused only when none of its name forms (internal name or display caption, in any bracket/derivation wrapping) appears anywhere. A field whose name merely collides with a used field in another datasource is treated as used.
This complements twb_field_usage(), which shows where each used field
appears across worksheets.
See also
twb_field_usage() for where used fields appear,
twb_calc_build_order() for rebuilding calculations in dependency order.
Examples
twb <- system.file("extdata", "rebuild_kit.twb", package = "twbparser")
stopifnot(nzchar(twb), file.exists(twb))
xml <- xml2::read_xml(twb)
# the fixture leaves exactly one raw field, one calc, and one parameter unused
twb_unused_fields(xml)
#> # A tibble: 3 × 7
#> datasource field_type name tableau_internal_name datatype role is_hidden
#> <chr> <chr> <chr> <chr> <chr> <chr> <lgl>
#> 1 sales-data calculated Unused C… [Calculation_0003] real meas… NA
#> 2 sales-data parameter Unused P… [Parameter 2] string dime… NA
#> 3 sales-data raw Unused F… [Unused Field] string dime… FALSE
# same result through the parser object
parser <- TwbParser$new(twb)
#> TWB loaded: rebuild_kit.twb
#> TWB parsed and ready
parser$get_unused_fields()
#> # A tibble: 3 × 7
#> datasource field_type name tableau_internal_name datatype role is_hidden
#> <chr> <chr> <chr> <chr> <chr> <chr> <lgl>
#> 1 sales-data calculated Unused C… [Calculation_0003] real meas… NA
#> 2 sales-data parameter Unused P… [Parameter 2] string dime… NA
#> 3 sales-data raw Unused F… [Unused Field] string dime… FALSE
parser$unused_fields
#> # A tibble: 3 × 7
#> datasource field_type name tableau_internal_name datatype role is_hidden
#> <chr> <chr> <chr> <chr> <chr> <chr> <lgl>
#> 1 sales-data calculated Unused C… [Calculation_0003] real meas… NA
#> 2 sales-data parameter Unused P… [Parameter 2] string dime… NA
#> 3 sales-data raw Unused F… [Unused Field] string dime… FALSE