ddbs_filter {duckspatial} | R Documentation |
Spatial Filter
Description
Filters data spatially based on a spatial predicate
Usage
ddbs_filter(
conn,
x,
y,
name = NULL,
predicate = "intersection",
crs = NULL,
crs_column = "crs_duckspatial",
overwrite = FALSE
)
Arguments
conn |
a connection object to a DuckDB database |
x |
a table with geometry column within the DuckDB database. Data is returned from this object |
y |
a table with geometry column within the DuckDB database |
name |
a character string of length one specifying the name of the table,
or a character string of length two specifying the schema and table names. If it's
NULL (the default), it will return the result as an |
predicate |
geometry predicate to use for filtering the data |
crs |
the coordinates reference system of the data. Specify if the data doesn't have crs_column, and you know the crs |
crs_column |
a character string of length one specifying the column
storing the CRS (created automatically by |
overwrite |
whether to overwrite the existing table if it exists. Ignored when name is NULL |
Value
an sf object or TRUE (invisibly) for table creation
Examples
## Not run:
## load packages
library(duckdb)
library(duckspatial)
library(sf)
## database setup
conn <- dbConnect(duckdb())
ddbs_install(conn)
ddbs_load(conn)
## read data
countries_sf <- st_read(system.file("spatial/countries.geojson", package = "duckspatial"))
argentina_sf <- st_read(system.file("spatial/argentina.geojson", package = "duckspatial"))
## store in duckdb
ddbs_write_vector(conn, countries_sf, "countries")
ddbs_write_vector(conn, argentina_sf, "argentina")
## filter countries touching argentina
ddbs_filter(conn, "countries", "argentina", predicate = "touches")
## End(Not run)