Column- or entry level access rights can provide additional access in two ways: by extending the rights to additional principals or by providing additional rights to the same principals. Of course, both ways can be combined. Following are some examples.
Assume a table object granted read rights to the table's owner:
Table 9-1 Table, Column, Entry Example 1| 
 | Nobody | Owner | Group | World | 
|---|---|---|---|---|
| Table Access Rights: | ---- | r--- | ---- | ---- | 
This means that the table's owner could read the contents of the entire table but no one else could read anything. You could then specify that Entry-2 of the table grant read rights to the group class:
Table 9-2 Table, Column, Entry Example 2| 
 | Nobody | Owner | Group | World | 
|---|---|---|---|---|
| Table Access Rights: | ---- | r--- | ---- | ---- | 
| Entry-2 Access Rights: | ---- | ---- | r--- | ---- | 
Although only the owner could read all the contents of the table, any member of the table's group could read the contents of that particular entry. Now, assume that a particular column granted read rights to the world class:
Table 9-3 Table, Column, Entry Example 3| 
 | Nobody | Owner | Group | World | 
|---|---|---|---|---|
| Table Access Rights: | ---- | r--- | ---- | ---- | 
| Entry-2 Access Rights: | ---- | ---- | r--- | ---- | 
| Column-1 Access Rights: | ---- | ---- | ---- | r--- | 
Members of the world class could now read that column for all entries in the table (light shading in Table 9-4). Members of the group class could read everything in Column-1 (because members of the group class are also members of the world class) and also all columns of Entry-2 (dark shading in Table 9-4). Neither the world nor the group classes could read any cells marked *NP* (for Nor Permitted).
Table 9-4 Table, Column, Entry Example 4| 
 | Col 1 | Col 2 | Col 2 | 
|---|---|---|---|
| Entry-1 | contents | *NP* | *NP* | 
| Entry-2 | contents | contents | contents | 
| Entry-3 | contents | *NP* | *NP* | 
| Entry-4 | contents | *NP* | *NP* | 
| Entry-5 | contents | *NP* | *NP* |