Get all the possible values of a column of a Marine Regions data product

Get all the possible values of a column of a Marine Regions data product

Usage

mrp_col_unique(layer, colname)

mrp_col_distinct(layer, colname)

Arguments

layer

(character) Identifier of the data product. See mrp_list

colname

(character) Column name in the data product. See mrp_colnames()

Value

A numeric or character vector with the unique values of a column of a Marine Regions data product.

Details

This function becomes useful to write CQL or OGC filters that you can pass to mrp_get() or mrp_view() as it helps to know all the possible values in the column name that you want to query on beforehand. Use it together with mrp_colnames() to know the columns and data types in the data product.

Geometry columns

Note that columns of type geometry are forbidden as their performance is sub-optimal and would likely crash your R session.

See also

mrp_list to describe the list of products, mrp_colnames() to get the names and data type of the columns of a data product, useful to write queries that can be passed to mrp_get() or mrp_view() via the arguments cql_filter or filter.

Examples

if (FALSE) {
mrp_col_unique("ecs", "pol_type")
mrp_col_unique("ecs_boundaries", "line_type")
}