require(RPostgreSQL)
require(df)

drv = dbDriver("PostgreSQL")
con = dbConnect(drv, dbname = DBname_1, user = DBuser, host = DBhost, port = DBport, password = DBpassword)

dat = st_read_db(con, table = "schema1.table1",
      query = "SELECT * FROM schema1.table1")

dbDisconnect(con)
dbUnloadDriver(drv)