将表格从R导入PostgreSQL DB

Question

I loaded some spatial data from my PostgreSQL DB into R with the help of the RPostgreSQL-package and ST_AsText :

dbGetQuery(con, "SELECT id, ST_AsText(geom) FROM table;")

After having done some analyses I want to go back that way. My geom column is stil formated as character / WKT. Unfortunately dbWriteTable doesn't accept similar arguments as dbGetQuery .

• What is the best way to import spatial data from R to PostgreSQL?

Up to now the only way I found, is importing the data into the DB and using ST_GeomFromText in an additional step to get my geometry data type.

Answer 1

I created a table on my DB by using dbWriteTable() and the postGIStools-package to INSERT the data (it must be a SpatialPolygonsDataFrame).

## Create an empty table on DB
dbWriteTable(con, name=c("public", "<table>"), value=(dataframe[-c(1:nrow(dataframe)), ]))
require(postGIStools)
## INSERT INTO
postgis_insert(con, df=SpatialPolygonsDataFrame, tbl="table", geom_name="st_astext")
dbSendQuery(con, "ALTER TABLE <table> RENAME st_astext TO geom;")
dbSendQuery(con, "ALTER TABLE <table> ALTER COLUMN geom TYPE geometry;")