Specifying column definitions

When you create a new table, you must specify a definition for each column. The fields that display for each column in the Columns view depend on your DBMS. You might not see all of the following fields, and the values that you can enter are dependent on the DBMS.

For more information, see your DBMS documentation.

Table 16-5: Defining columns in the Columns view in the Database painter

Field

What you enter

Column Name

(Required) The name by which the column will be identified.

Data Type

(Required) Select a datatype from the drop-down list. All datatypes supported by the current DBMS are displayed in the list.

Width

For datatypes with variable widths, the number of characters in the field.

Dec

For numeric datatypes, the number of decimal places to display.

Null

Select Yes or No from the Null drop-down list to specify whether NULLs are allowed in the column. Specifying No means the column cannot have NULL values; users must supply a value. No is the default in a new table.

Default

The value that will be placed in a column in a row that you insert into a DataWindow object. The drop-down list has built-in choices, but you can type any other value. For an explanation of the built-in choices, see your DBMS documentation.