Keys for Split Tables

For a data set with keys, the keys of the original data set are duplicated in the split tables because you must access each of these tables individually. The process of splitting the data set into tables continues until there are no more data items left in the data set.

The following examples show the mapping of a data set that has 600 items (5 of which are keys) to a relational database that limits the number of columns in a table to 250. The result is tables that contain a total of 610 columns, where the 5 keys are duplicated across all 3 tables. If the original table is named savings, the remaining two tables are named savings1 and savings2, unless these names are already in use.




250 columns (first 5 are keys)

5 keys and 245 columns

5 keys and 105 columns

The five keys are duplicated in each table. To search these split tables, you must explicitly open each table. The tables are not automatically linked.