R/driver-spark.R

In rstats-db/odbc: Connect to ODBC Compatible Databases (using the DBI Interface)

#' @export
#' @rdname DBI-classes
setClass("Spark SQL", contains = "OdbcConnection")

# Databricks supports multiple catalogs.  On the other hand,
# the default implementation of `odbcConnectionSchemas` which routes through
# `SQLTables` is likely to enumerate the schemas in the currently active
# catalog only.
#
# This implementation will respect the `catalog_name` arrgument.
setMethod("odbcConnectionSchemas", "Spark SQL",
  function(conn, catalog_name = NULL) {
    if (is.null(catalog_name)) {
      return(callNextMethod())
    }
    res <- dbGetQuery(conn, paste0("SHOW SCHEMAS IN ", catalog_name))
    if (nrow(res)) {
      return(res$databaseName)
    }
    return(character())
  }
)


#' @export
#' @rdname odbcDataType
#' @usage NULL
setMethod("odbcDataType", "Spark SQL",
  function(con, obj, ...) {
    switch_type(
      obj,
      factor = "VARCHAR(255)",
      datetime = "TIMESTAMP",
      date = "DATE",
      binary = "BINARY",
      integer = "INT",
      int64 = "INT",
      double = "DOUBLE",
      character = "VARCHAR(255)",
      logical = "BOOLEAN",
      list = "VARCHAR(255)",
      time = ,
      stop("Unsupported type", call. = FALSE)
    )
  }
)