What is the ‘Union’ task?
The ‘Union’ task can be used to combine and consolidate data from multiple input data tables. The output table of the ‘Union’ task, can contain all columns from all input tables, or only the columns that are common to all the input tables.
The ‘Union’ task can be used to not just quickly combine data, but also to identify data gaps, and avoid issues in further analysis.
How to use the ‘Union’ task?
The important fields in the ‘Union’ task are
- Select Table
Use this dropdown menu to select the table on which you would like to perform the ‘Union’ task. Use the ‘Add Field’ option to add more tables if needed.
- Select Union Type
Use this dropdown menu to select the type of union. You may select ‘Auto Config By Name’ to match column names of the input tables, or ‘Auto Config By Position’ to ignore column names of input tables, and arrange by their positions.
- Column Output Type
Use this dropdown menu to select the columns in the output table. You may select ‘Output All Columns’ or ‘Output Common Columns’.
- Add Table Name Column
Use this checkbox to indicate if you would like to include a column for table name. If selected, the output table will have a column named ‘Table Name’, and the entries in this column will be the names of the corresponding input table.
How to use the ‘Define Output Table’ and the ‘Output Options’ sections in the ‘Union’ task?
The ‘Output Options’ section in the ‘Union’ task can be used to modify features of the output table. The fields related to this section become visible on selecting the ‘Output Options’ checkbox.
More information about this section is available here.