Data Control Statements

Data control statements let you define security for your database. When you create a dictionary, no security is defined for it until you explicitly enable security for that dictionary. Pervasive.SQL allows you to construct data control statements to do the following:

Enable and disable security.

Create and delete users and groups.

Grant and revoke rights.

Note
If your Btrieve data files are secured using Btrieve owner names, the Relational Engine will honor them when performing ODBC operations (for example, Read Only access will be permitted with a type 1 or 3 owner name, no access with a type 0 or 2 owner name) if your database is not secured using Relational security. If your database is secured using Relational security, the Relational Engine will enforce access to the database solely based on the defined database user access rights when performing ODBC operations. These rights must be granted with the owner name specified.

The following sections briefly describe the SQL statements associated with each of these tasks.

Enabling and Disabling Security

You can enable or disable security for a database by issuing statements using the following statement:

Table 1-15 Data Control Statements-Security


SET SECURITY	Enables or disables security for the database and sets the Master password.

Creating and Deleting Users and Groups

You can create or delete users and user groups for the database by constructing SQL using the following statements:

Table 1-16 Data Control Statements-Groups and Users


CREATE GROUP	Creates a new group of users.
DROP GROUP	Deletes a group of users.
GRANT LOGIN TO	Creates users and passwords, or adds users to groups.
REVOKE LOGIN FROM	Removes a user from the dictionary.

Granting and Revoking Rights

You can assign or remove rights from users or groups by issuing statements using the following:

Table 1-17 Data Control Statements-Rights


GRANT (access rights)	Grants a specific type of rights to a user or a group. The rights you can grant with a GRANT (access rights) statement are All, Insert, Delete, Alter, Select, Update, and References.
GRANT CREATETAB TO	Grants the right to create tables to a user or a group.
REVOKE (access rights)	Revokes access rights from a user or a group.
REVOKE CREATETAB FROM	Revokes the right to create tables from a user or a group.