Initializing help system before first use

# Adding and Manipulating Decision Table Columns and Rows

Decision table columns determine the names and types of the table's inputs and outputs, specific values are set in the rows of the decision table itself.

## Adding and Manipulating Decision Table Columns

Decision tables can have two column types:

- Simple columns: whereby a match is checked by comparing the input value to the corresponding value in the table. This simple type can contain strings or numbers.
- Range columns: where a match is checked by comparing the input value to a range defined in the table. Range columns can also be used to display the data by series, and to provide a filter.

Columns and their values are managed in the Column Manager, launched by clicking OPEN COLUMN MANAGER in the decision table editor. Columns can be dragged in the Decision Table Editor after they have been added to re-order them.

Simple columns can contain either numbers or strings. When processing simple columns, Xpress Insight infers their type by examining the type of the first non-wildcard (*) column it discovers as it scans rows from left to right.

- To add a simple input column, type a suitable name in the first empty Header field, select SIMPLE in the Type drop-down list and click ADD in the last column.

  Wildcard values are not plotted, and so can be used to hide rows.

- To add a range column, type a suitable name in the first empty Header field, select RANGE in the Type drop-down list, select an item in the Operator drop-down list and click ADD in the last column. The lower and upper bounds of range keys are added as later edits to table rows. The Operator field can be set to one of four values:

  < .. <= | The range does not include its lower bound but includes its upper bound.
  <= .. < | The range includes its lower bound but does not include its upper bound.
  < .. < | The range does not include either its lower bound or its upper bound.
  <= .. <= | The range includes both its lower bound and its upper bound.

The figure shows the result of adding a simple column, a range column and an output value to a new table. Note that the value selected as an Operator contains essential whitespace: `[operator][space]..[space][operator]`. This is especially important to bear in mind if you decide to edit a decision table in a text editor as a CSV file. For more, see Editing Decision Tables as CSV files.

Column Manager edits that have not been saved are denoted by an asterisk (*) following the column ids in the first column. Click UPDATE to save them. Click CLOSE to dismiss the Column Manager—a warning appears if you have unsaved changes.

## Adding and Manipulating Decision Table Rows

While the names and types of decision table inputs and outputs are managed in the Column Manager, each row in a decision table defines a combination of specific inputs that triggers a specific output.

- To add a row to a decision table, click ADD ROW.
  - To set values for simple columns, replace the asterisks(*) with specific values.
  - To set the bounds of range columns, replace the asterisks(*) in the relevant cells with the bounding values.
    The figure shows the result of configuring a decision table to emit an output-1 value of 5 if it receives an input-2 value above 1 and less than or equal to 2. Note the asterisk(*) in the input-1 cell-this is a wildcard and for this row, means that the logic permits any value of input-1.
  - You can copy and paste table data and undo changes.
- Click SAVE and then CLOSE to dismiss the dialog.

Parent Topic Using the Decision Table Editor

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