About maintaining columns on SQL tables
To add, delete, or modify columns on tables, use the Sql Columns form. However, understand that you cannot make changes to certain restricted tables.
Caution:
You can add columns, but do
not delete or modify columns on existing base application tables. Doing so can cause system
instability.
Note: System administrators can use the Metadata Access
Controls form to restrict access to core SQL tables. You cannot modify SQL
tables that are set to in the
Metadata Access Controls form. You can view SQL tables that are set
to but you cannot modify them. You can
view and modify SQL tables that are set to .
To add a new column to a table that already contains columns, the new column must meet at least one of these conditions:
- Allows nulls
- Has a default definition specified
- Is an identity or timestamp data type
If none of these conditions is true, then the column can be added only to an empty table.
You can also change the definition of an existing column, for example, the data type.