Check if a field is required

Indicates whether this field is allowed to be NULL. If required is TRUE, then NULL is disallowed. See the section on missingValues for how, in the physical representation of the data, strings can represent NULL values.

constraints.checkRequired(constraint, value)

Arguments

constraint	set TRUE to check required values
value	value to check

Value

TRUE if field is required

See also

Constraints specifications

Examples

constraints.checkRequired(constraint = FALSE, value = 1)
#> [1] TRUE

constraints.checkRequired(constraint = TRUE, value = 0)
#> [1] TRUE

constraints.checkRequired(constraint = TRUE, value = NULL)
#> [1] FALSE

constraints.checkRequired(constraint = TRUE, value = "undefined")
#> [1] FALSE