R to Hive utils

rhive.R

dbBuildTableDefinition.hive =
  function (databasename, tablename, df, field.types = NULL, s3path)
  {
    if (!is.data.frame(df))
      df <- as.data.frame(df)
    if (is.null(field.types)) {
      field.types <- lapply(df, hiveDataType)
    }
    flds <- paste(names(field.types), field.types)
    base = sprintf("CREATE EXTERNAL TABLE %s.%s
                   (%s)
                   ROW FORMAT DELIMITED 
                   FIELDS TERMINATED BY '\\u0001' 
                   COLLECTION ITEMS TERMINATED BY '\\u0004' 
                   MAP KEYS TERMINATED BY '\\u0002' 
                   STORED AS INPUTFORMAT 
                   'org.apache.hadoop.mapred.TextInputFormat' 
                   OUTPUTFORMAT 
                   'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat'
                   LOCATION
                   '%s'", databasename, tablename,
                   paste(flds, collapse = ",\n"),
                   s3path)
    return (base)
  }

hiveDataType = function (obj)
{
  rs.class <- data.class(obj)
  rs.mode <- storage.mode(obj)
  if (rs.mode %in% c("integer", "int") & rs.class == 'numeric') "int"
  else switch(rs.class,
              character = "string",
              logical = "tinyint",
              Factor = "string",
              Date = "int",
              POSIXct = "string",
              numeric = "double",
              "string")
}