constraints.checkRequired

Indicates whether this field is allowed to be <code>NULL</code>. 
If required is <code>TRUE</code>, then <code>NULL</code> is disallowed.
See the section on <a href="https://specs.frictionlessdata.io//table-schema/#missing-values">missingValues</a> for how, 
in the physical representation of the data, strings can represent <code>NULL</code> values.

Allows to work with 'Table Schema' (<https://specs.frictionlessdata.io/table-schema/>). 'Table Schema' is well suited for use cases around handling and validating tabular data in text formats such as 'csv', but its utility extends well beyond this core usage, towards a range of applications where data benefits from a portable schema format. The 'tableschema.r' package can load and validate any table schema descriptor, allow the creation and modification of descriptors, expose methods for reading and streaming data that conforms to a 'Table Schema' via the 'Tabular Data Resource' abstraction.

Kleanthis Koupidis

tableschema.r

Table Schema 'Frictionless Data'

Lazaros Ioannidis

Charalampos Bratsas

Open Knowledge International 

constraints.checkRequired function

<dl><dt>constraint</dt>
<dd>set TRUE to check required values</dd>
<dt>value</dt>
<dd>value to check</dd></dl>

Arguments

Indicates whether this field is allowed to be <code>NULL</code>. 
If required is <code>TRUE</code>, then <code>NULL</code> is disallowed.
See the section on <a href='https://specs.frictionlessdata.io//table-schema/#missing-values'>missingValues</a> for how, 
in the physical representation of the data, strings can represent <code>NULL</code> values.

Check if a field is required — constraints.checkRequired

<dl>

<dt>constraint</dt>
<dd>set TRUE to check required values</dd>


<dt>value</dt>
<dd>value to check</dd>

</dl>

constraints.checkRequired: Check if a field is required

Description

Usage

Value

Arguments

See Also

Examples