Using Expressions to Create a New Column - MapInfo_Pro - 2023

You can create a new column by applying an expression to an existing column, or modifying the expression that defines an existing column. A column you modify or create using an expression is for display purposes only. Modifications are not saved with the Browse window. To create an expression that can be saved, create the expression through the SQL Select command.

To create a new Browser window display column:

1. On the TABLE tab, in the Browser Tools group, click Pick Fields to open the Pick Fields dialog box.
2. Choose Expression from the Fields in Table drop-down list, or click Assist, to open the Expression dialog box.
3. Type an expression or create an expression by choosing parameters from the Columns, Operators, and/or Functions drop-down lists.
4. Choose Verify to validate the syntax of the expression. This step is optional.
5. The expression displays in the Edit Browser Column section within the Name and Expression boxes. Choose OK to accept the expression.
6. Choose OK if the information in the Name and Expression boxes is accurate.

Editing the Expression that Defines a Column

You use a column you modify or create using an expression is for display purposes only. Modifications are not saved with the Browser window. To create an expression that can be saved, create the expression through the SQL Select command.

There are two methods for defining an expression:

• Change the text in the Edit Expression box or
• Select the Assist option to display the Expression dialog box containing drop-down lists of columns, operators and functions

Editing a Column Name

To edit a column name:

1. On the TABLE tab in the Browser Tools group, click Pick Fields to open the Pick Fields dialog box.
2. Choose a column from the Columns in Browser list.
3. Position the cursor in the name box.
4. Enter the new column name.
5. Click OK to save your change.

Editing an Expression Using Assist

To edit the expression that defines a column using Assist:

1. On the TABLE tab, in the Browser Tools group, click Pick Fields to open the Pick Fields dialog box.
2. Choose the text in the Expression box to make the Assist button active.
3. Click Assist to open the Expression dialog box.
4. Create the expression by choosing parameters from the Columns, Operators, and Functions drop-down lists.
5. Choose OK to execute the expression and create a new column display in the Browser window. The new column displays as the right most column in the table.

Editing an Expression by Changing Text

To edit the expression that defines the column by changing the text in the expression box:

1. On the TABLE tab, in the Browser Tools group, click Pick Fields to open the Pick Fields dialog box.
2. Choose the column name in the Columns in Browser column. The column name and expression display in the Edit Expression Name and Expression boxes.
3. Type a new expression in the Expression box.
4. Choose OK to execute the expression and create a new display column in the Browser window.