Command Discussion

• REVOKE is a required keyword that indicates you are removing access to tables .

• Privilege refers to the type of privilege or privileges you are revoking. One or more of the following privileges can be revoked: SELECT, INSERT, UPDATE, DELETE, and ALTER. Alternatively, ALL can be specified if all of the above actions are to be taken away from the user.

• The ON clause indicates the table(s) from which these privileges are being removed.

• PUBLIC is used if the privileges are taken away from all users of the indicated table(s). Otherwise, you list the user names of only those who are no longer allowed to share the table.

Example: The Personnel clerks no longer need to access the EMPLOYEE table. Revoke their privileges as follows:

     REVOKE  UPDATE, INSERT
     ON      EMPLOYEE
     FROM    CLERK1, CLERK2 ;

This completes the discussion of security features in TEXIS. In the next chapter, you will be introduced to certain other administrative features that can be implemented in TEXIS.