ALTER USERGROUP Statement (alter_usergroup_statement)
The ALTER USERGROUP
statement (alter_usergroup_statement
)
changes the properties assigned to a user group.
Syntax
<alter_usergroup_statement> ::=
ALTER USERGROUP <usergroup_name>
[<usergroup_mode>]
[TIMEOUT <unsigned_integer> | TIMEOUT NULL]
[COSTLIMIT <unsigned_integer> | COSTLIMIT NULL]
[DEFAULT ROLE ALL [EXCEPT <role_name>]
| DEFAULT ROLE NONE
| DEFAULT ROLE <role_name>]
[[NOT] EXCLUSIVE]
[DEFAULTCODE <ascii_or_unicode>]
[<connect_mode>]
<usergroup_mode>::=
RESOURCE
| STANDARD
<ascii_or_unicode>::=
ASCII
| UNICODE
<connect_mode> ::=
ENABLE CONNECT
| DISABLE CONNECTAt least one of the optional clauses must be specified. The specified user group must be a defined user group.
The current database user must have the right of ownership for
the user group for which the properties are to be changed. The members of
the specified user group must not be logged onto the database system when
the ALTER USERGROUP
statement is executed.
You use usergroup_mode
to specify
a database user class for this user group.
Database User Class |
Properties |
|---|---|
DBA |
Database administrators Users belonging to this class can:
|
RESOURCE |
Users belonging to this class can:
|
STANDARD |
Users belonging to this class can:
|
RESOURCE: This specification means that the
user group is to be assigned to the database user class RESOURCE
.
STANDARD: This specification means that the user group will have its current database user class withdrawn and will lose the right to hold its own data. All existing base tables created by the user group are deleted.
No database user class: If a database user class has not been specified, the database user class of the user group remains unchanged.
The timeout
value is specified in seconds and must be between 30
and 32400
.
Only the database system administrator can define database users with the
timeout value 0
.
If the NULL value is specified, the value defined previously is canceled.
This specification limits costs by preventing specified database
users from executing QUERY
statements or INSERT
statements
in the form of INSERT...SELECT...
beyond a
specified degree of complexity, which would otherwise be cost-intensive. COSTLIMIT specifies
the estimated SELECT cost value beyond which the SQL statement is not executed.
Before these SQL statements are executed, the costs expected to
result from this statement are estimated. This SELECT
cost
estimate can be output using the EXPLAIN
statement. In interactive mode, the estimated SELECT
cost
value is compared with the COSTLIMIT
value
specified for the database user. The COSTLIMIT
value
is ignored with QUERY
statements or INSERT
statements
of the form INSERT...SELECT...
that are embedded
in a programming language.
If the NULL
value is specified,
the value defined previously is canceled.
DEFAULT ROLE
defines which of the
roles assigned to the database user/user group is activated automatically
when a database session is opened.
ALL: All roles assigned to the database user/user
group are activated when a session is opened. EXCEPT
can
be used to exclude specified roles from activation.
NONE: None of the roles are active when a database session is opened by a database user/member of a database user group.
Role name specified: The roles specified here must exist and be assigned to the database user/user group. They are activated automatically when a database session is opened for a database user/member of a database user group.
If the EXCLUSIVE
syntax rule is
not specified, NOT EXCLUSIVE
is assumed implicitly.
EXCLUSIVE: This prevents the specified database user from opening two different database sessions simultaneously.
NOT EXCLUSIVE: Allows the database user to open several database sessions simultaneously.
The value of the special
database parameter DefaultCodePage
is
overridden with the code
attribute ASCII
or UNICODE
specified
in syntax rule DEFAULTCODE <ascii_or_unicode>
for
objects of the specified database user.
You can use connect_mode
to define
whether a database user can open database sessions. For CREATE
USERGROUP
statement this is only valid however if CONNECT
mode
(connect_mode
) is not specified in the CREATE
USER
statement.
If CONNECT
mode is not specified, ENABLE
CONNECT
is implicitly assumed. ENABLE
and DISABLE
cannot
both be specified at the same time.
ENABLE CONNECT: The database user (members of the database user group) can open database sessions.
DISABLE CONNECT: The database user (members
of the database user group) cannot open database sessions. ALTER
USER|USERGROUP
statement: The database sessions of the specified
database user (members of the specified database user group) are terminated.
You can enable the individual members of a database user group to open database
sessions again using the ALTER USER
statement.