External tables are created as described in the previous section and
the definition of their content is taken from the format file specified.
To create a user table one can also use the CREATE/TABLE command
by giving NULL as input. This will create a table of the specified
size where all elements are NULL.
Columns in a table can be created or deleted by using the commands
CREATE/COLUMN and DELETE/COLUMN.
The available commands are collected in
Table 
.
Table: Commands to Define Tables
Some commands use internal tables to store results. In such cases the tables will be created and defined by the system according to defaults. Labels, display formats and units in an existing column are modified by the NAME/COLUMN command.