Class Structure

The dbSpatial package is designed to work with spatial geometries in a DuckDB table. The package builds on the DuckDB spatial extension.

dbSpatial objects adopt the S4 class system and represent spatial geometries in a DuckDB table. The {dbSpatial} package consists of methods for constructing dbSpatial objects from various data sources, as well as various spatial operations for working with these data.

dbSpatial provides methods for reading/writing dbSpatial objects from/to data.frames, S3 and S4 spatial-related objects (e.g. objects from {sf} or {terra}), and several other spatial files that are supported by the DuckDB spatial extension.

The runnable example below is evaluated only when the duckdb package is available in the check environment.

library(dbSpatial)

con <- DBI::dbConnect(duckdb::duckdb(), ":memory:")
DBI::dbExecute(con, "SET threads = 1")
#> [1] 0
coords <- data.frame(id = 1:3, x = c(0, 1, 2), y = c(0, 1, 2))

pts <- dbSpatial(
  conn = con,
  name = "class_structure_points",
  value = coords,
  x_colName = "x",
  y_colName = "y",
  overwrite = TRUE
)

class(pts)
#> [1] "dbSpatial"
#> attr(,"package")
#> [1] "dbSpatial"
pts
#> # Class:    dbSpatial 
#> # Source:   SQL [?? x 4]
#> # Database: DuckDB 1.4.2 [unknown@Linux 4.18.0-553.124.1.el8_10.x86_64:R 4.5.2/:memory:]
#>      id     x     y geom       
#>   <int> <dbl> <dbl> <chr>      
#> 1     1     0     0 POINT (0 0)
#> 2     2     1     1 POINT (1 1)
#> 3     3     2     2 POINT (2 2)

DBI::dbDisconnect(con, shutdown = TRUE)