Select_data
selection-functions select_data
OBSOLETE: replaced by collect_by_cond
syntax
- select_data(domain-unit, condition, attribute)
definition
The select_data(domain unit, condition, attribute) function relate the attribute argument to the domain unit argument based on the condition argument.
The select_data is mostly used together with the select_with_attr_by_cond function.
applies to
- unit domain unit with value-type uint32
- condition must be a boolean attribute or subexpression resulting in boolean values.
- attribute: an attribute that must have a matching value type and metric with the resulting attribute.
since version
7.305 until 15.0.0
example
unit<uint32> ZHCities := select_with_attr_by_cond(City, City/RegionCode == 200)
{
attribute<string> name :=
select_data(., City/RegionCode == 200, CityLabels/Name);
}
City/RegionCode | CityLabels/Name |
---|---|
100 | Amsterdam |
200 | Rotterdam |
300 | Utrecht |
200 | Den Haag |
400 | Eindhoven |
null | Haarlem |
400 | Tilburg |
domain City, nr of rows = 7
ZHCities/name |
---|
Rotterdam |
Den Haag |
domain ZHCities, nr of rows = 2