Group Tab

Use the Group tab for group selection, which extracts a number of rows based on values in a particular column in the Start Table.

Note: Group selection is typically used in an Extract Process to select data for a test database. The Group tab is not available and the settings on it do not apply when archiving, editing, or browsing database tables.
access definition group tab where you select the column to be searched and the number of rows to extract

Column Name

Name of the Start Table column used to select the data to extract. For example, you can extract a set of customer data based on values in the STATE column in the CUSTOMERS table. Click the arrow to select a column name.

Number of Unique Groups

Number of groups to extract. Rows in each group have the same value in the selected Start Table column, but the value is different for each group. To select a group for each unique value, leave the box blank.

Number of Rows per Group

Maximum number of rows to extract for each unique value in the selected Start Table column. To select all rows per group, leave the box blank.

Note: For group selection, you must specify a Number of Unique Groups, a Number of Rows per Group, or both.

Examples

As an example of group selection, you can extract a set of data based on values in the STATE column in the CUSTOMERS table:

  Number of Unique Groups Number of Rows per Group
To extract all rows of customer data from any 10 states. 10 blank
To extract 50 rows of customer data from all states. blank 50
To extract 50 rows of customer data from any 10 states. 10 50

You can combine selection criteria or an SQL WHERE clause with Group options. In this example, you can specify selection criteria to target up to 10 specific states.

Note: When criteria are used in combination with Group Selection parameters, the criteria are applied first with Group Selection parameters applied to the result. In the example, if you provided selection criteria for three states, three groups would be selected. If, however, you provided criteria for 11 states, only 10 groups would be selected.

For details on selection criteria, see Table Specifications.