Format of exported data records
Exported data records share a common format, but the content of the tables and columns is product-specific. The topics in this section describe the format of the dictionary entries.
A single dictionary data set contains a description and mapping information for every table recorded in the original data set. In many cases, the tables have variable-length columns and some rows of data where columns are not available. The information about missing columns and lengths for variable columns is embedded in the data records. Some tables have columns that physically overlay each other. This must be taken into account when trying to obtain data for these overlays.
- Section 1 describes general information about the data source used to create the exported data.
- Section 2 contains a dictionary required for mapping the data.
- Section 3 contains the actual data rows.
The historical data is maintained in relational tables. Therefore, the dictionary mappings provide table and column information for every table that had data recorded for it in the persistent data store.