ALTER DBSLICE ADD DBSPACE

Use the onutil ALTER DBSLICE ADD DBSPACE command to add dbspaces to a dbslice. You can either add dbspaces to a dbslice on the coservers where they were created or expand a dbslice to another coserver.

The onutil ALTER DBSLICE ADD DBSPACE command does not move or redefine user data. After you alter the dbslice, you can store new tables in either the new or old dbspaces.

These new dbspaces are not automatically visible to the existing tables in the dbslice. Refragment the existing tables to enable them to use the new dbspaces in the dbslice. To refragment existing tables, use the ALTER FRAGMENT command, described in the IBM Informix: Guide to SQL Syntax.

Syntax

>>-ALTER DBSLICE--dbslice_name--ADD DBSPACE--FROM--------------->

   .-,---------------------.
   V                       |
>----| Dbslice Component |-+-----------------------------------><

Dbslice Component:

                                             (1)
|--| SIZE size Pathname Coserver Component |-------------------->

>--+--------------------+--+----------------------+--CHUNK------>
   '-THRESHOLD--percent-'  '-FRAGMENTS--fragments-'

                           (2)
>--| Pathname Definition |-------SIZE--size--+--------+--------->
                                             +-KBYTES-+
                                             +-MBYTES-+
                                             '-GBYTES-'

>--+--------------------------------------+---------------------|
   |                                 (3)  |
   '-MIRROR--| Pathname Definition |------'

Notes:

Element	Purpose	Restrictions	Syntax
dbslice_name	The name of the dbslice to alter	The dbslice must exist.	See Dbslice Name.
fragments	The approximate number of fragments each new dbspace will contain	Value is between 3 and 65500	Decimal or hexidecimal integer.
percent	The percentage of total space in the dbspace which, when used, triggers an alarm.	Value is between 1 and 100	Decimal or hexidecimal integer.
size	The size of the initial chunk of each new dbspace	Value must be greater than 0. Size must not exceed 4 gigabytes. Can specify units of kilobytes, megabytes, or gigabytes.	Unsigned integer; default unit is kilobytes.

Coserver Component

Coserver Component:

|--COGROUP--+-cogroup_name--------------+-----------------------|
            +-coserver_name-------------+
            '-coserver_range_identifier-'

Element	Purpose	Restrictions	Syntax
cogroup_name	The name of a cogroup in the database server	The cogroup name must exist when you execute the command. Name must be unique within a database server.	See Cogroup Name.
coserver_name	The name of a coserver that the database server automatically generates. A coserver name has the following format: dbserername.coserver_number		See Coserver Name.
coserver_range _identifier	The range of coservers in the dbslice. Coserver range identifiers can include embedded formatting characters of the following form: %r(first..last)	These formatting characters are replaced by integer values in the range that first and last specify to produce a list of coserver names.	See Coserver Range Identifier.

Pathname Definition

Pathname Definition:

|--+-| Pathname Format |-+--+----------------+------------------|
   +-"-------------------+  '-OFFSET--offset-'
   +-pathname------------+
   '-"-------------------'

Pathname Format:

              .-----------------------------------.
              V                                   |
|--"--prefix----+-------------------------------+-+--"----------|
                +-pathname_fragment-------------+
                +-%c----------------------------+
                +-%n----------------------------+
                +-%o----------------------------+
                |                          (1)  |
                +-%f--(--first--"--last--)------+
                '-,-----------------------------'

Notes:

Each item can occur only once. However, multiple items may occur in a single invocation of the command.

Element	Purpose	Restrictions	Syntax
first	The starting value of the integer to substitute for each path When first is in the pathname, its value can be any integer that makes each generated pathname unique.	The value of first must be equal to or less than the value of last.	Unsigned integer
last	The ending value of the integer to substitute in each path When last is in the pathname, its value can be any integer that makes each generated pathname unique.	The value of last must be equal to or larger than first.	Unsigned integer
offset	The offset, in kilobytes, into the file or raw device to reach the chunk of each dbspace	Value must be greater than or equal to 0. See specifying an offset in the chapter on managing disk space in the IBM Informix: Administrator's Guide.	Unsigned integer
pathname	The file or raw device of the first chunk in the dbspace on each node The pathname can optionally contain formatting characters.	The chunk must be a file or raw device. Use a full pathname.	Pathname must conform to the rules specific to your operating system. See Pathname Format.
prefix	The portion of the directory name pathname that precedes the formatting character	The directory name must correspond to files that exist on the applicable coservers.	The directory name must conform to the rules specific to your operating system.
pathname_ fragment	The portion of the generated pathname that follows the formatting characters	The generated pathnames must correspond to files that exist on the applicable coservers. You can intersperse the formatting characters in between parts of the pathname.	Pathname must conform to the rules specific to your operating system. See Pathname Format.
%c	A formatting character that is replaced with the number of the coserver on which a dbspace is to be created. The number is the value that you specified in the COSERVER configuration parameter for this coserver.	If the number is less than 10, the number does not have a leading zero.	See Generating Pathnames with Coserver Numbers.
%n	A formatting character that is replaced with the host name of the node for the coserver on which a dbspace is to be created.	The host name is the value that you specified in the NODE configuration parameter for this coserver.	See Generating Pathnames with Node Names.
%o	A formatting character that is replaced with the ordinal number of a dbspace within a dbslice	The ordinal number starts numbering at 1 plus the old dbspace count of the dbslice.	See Generating Pathnames with Dbspace Ordinal Numbers.
%r(first..last)	Formatting characters that are replaced by successive integer values in the range that first and last specify	You can specify the %r(first..last) formatting characters only once in a pathname format.	See Generating Pathnames for Multiple Dbspaces per Coserver.

Usage

Use the onutil ALTER DBSLICE ADD DBSPACE command to add dbspaces to a dbslice on one or more coservers. The new dbspaces do not need to be the same size as the old dbspaces in the dbslice. The database server must be in online or quiescent mode when you alter a dbslice.

Before you alter the dbslice, use the touch command to allocate storage for the chunk files. Use any chunk name that you want. The database server derives the dbspace names from the dbslice name and a dbspace identifier. For more details, see Derived Dbspace Identifier.

The new dbspaces in the dbslice are the same type as the original dbspaces in the dbslice. If you alter a dbslice that contains mirrored dbspaces, the new dbspaces are also mirrored. If you alter a temporary dbslice, the new dbspaces are also temporary dbspaces.