Understanding the SPD Server Table File Format

SPD Server organizes data into a streamlined file format that has advantages for a distributed file system like HDFS. The advantages of the SPD Server file format include the following:
  • Data is separate from the metadata. The file format consists of separate files: one for data, one for metadata, and two for indexes. Each type of file has an identifying file extension. The extensions are .dpf for data, .mdf for metadata, and .hbx and .idx for indexes.
  • The SPD Server file format partitions the data by spreading it across multiple files based on a partition size. Each partition is stored as a separate physical file with the extension .dpf. Depending on the amount of data and the partition size, the data can consist of one or more physical files, but is referenced as one logical file.
    The default partition size is 128 megabytes. You can specify a different partition size with the SPDSSIZE= macro variable or the PARTSIZE= table option. For more information, see the SPDSSIZE= Macro Variable and the PARTSIZE= Table Option.