Add support for tables defined via DBI::Id(schema = "my_schema", table = "my_table")

[bschulth]

Currently, if you have a multi-schema database, you cannot access schema specifically using the

• DBI::Id functionality.

  • https://dbi.r-dbi.org/reference/id

  •   table <- DBI::Id(schema = "my_schema", table = "my_cars")
      DBI::dbWriteTable(conn, name = table, value = mtcars, overwrite=FALSE, append=TRUE)

  • Ideally all of the functions would use DBI::dbQuoteIdentifier to resolve the table object, or use slots

  •  DBI::dbQuoteIdentifier(conn, table)
    
     # <SQL> "my_schema"."my_cars"

• As such when trying to update tables with dbWriteTable in a particular schema and you want to not overwrite, but append, the code will error out because things like dbExistsTable fail to detect the table already exists in the other schema.