Create a Dbspace or Temporary Dbspace

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Create a Dbspace or Temporary Dbspace

Create a Dbspace or Temporary Dbspace:
 
|-- -c---- -d--dbspace----+- -p--pathname---------------+------->
                          |                        (1)  |
                          '- -p--\--\--.--\--drive------'
 
>-- -o--offset-- -s--size--------------------------------------->
 
>--+------------------------------------+----------------------->
   +- -ef--extentsize-- -en--extentsize-+
   '- -t--------------------------------'
 
>--+------------------------------------+--+---------------+----|
   +- -m--pathname offset---------------+  '- -k--pagesize-'
   |                               (1)  |
   '- -m--\--\--.--\--drive offset------'

Notes:

Windows Only

Element	Purpose	Key Considerations
-c	Creates a dbspace You can create up to 2047 storage spaces of any type.	Additional Information: After you create a storage space, you must back up both this storage space and the root dbspace. If you create a storage space with the same name as a deleted storage space, perform another level-0 backup to ensure that future restores do not confuse the new storage space with the old one. References: For more information, see creating a dbspace in the chapter on managing disk space in the IBM Informix Administrator's Guide.
drive	Specifies the Windows drive to allocate as unbuffered disk space The format can be either \\.\<drive>, where drive is the drive letter assigned to a disk partition, or \\.\PhysicalDrive<number>, where PhysicalDrive is a constant value and number is the physical drive number.	References: For information on allocating unbuffered disk space, see allocating unbuffered disk space on Windows in the chapter on managing disk space in the IBM Informix Administrator's Guide.Examples: \\.\F: \\.\PhysicalDrive2 References: For pathname syntax, see your operating-system documentation.
-d dbspace	Names the dbspace to be created	Restrictions: The dbspace name must be unique and cannot exceed 128 characters. It must begin with a letter or underscore and must contain only letters, numbers, underscores, or the $ character. References: For more information, see creating a dbspace, in the chapter on managing disk space in the IBM Informix Administrator's Guide. The syntax must conform to the Identifier segment. For more information, see the IBM Informix Guide to SQL: Syntax.
-ef extentsize	Indicates, in kilobytes, the size of the next extents in the tblspace tblspace	Restrictions: The minimum size of the next extents for the tblspace tblspace of a non-root dbspace is equivalent to 4 dbspace pages, specified in K. For example: 8 KB for a 2 KB page size dbspace, 16 KB for a 4 KB page size dbspace, 32 KB for an 8 KB page size dbspace. The default size for a next extent is 50 dbspace pages. The maximum size of a tblspace tblspace extent is 1048572 pages. On a 2 KB pagesize system this would evaluate to approximately 2 GB. If there is not enough space for a next extent in the primary chunk, the extent is allocated from another chunk. If the specified space is not available, the closest available space is allocated. References: For more information, see specifying first and next extent size in the chapter on managing dbspaces in the IBM Informix Administrator's Guide.
-en extentsize	Indicates, in kilobytes, the size of the first extent for the tblspace tblspace	Restrictions: The minimum, and default, size of the first extent for the tblspace tblspace of a non-root dbspace is equivalent to 50 dbspace pages, specified in K. For example: 100 KB for a 2 KB page size dbspace, 200 KB for a 4 KB page size dbspace, 400 KB for an 8 KB page size dbspace. The maximum size of a tblspace tblspace extent is 1048575 pages minus the space needed for any system objects. On a 2 KB pagesize system this would evaluate to approximately 2 GB. References: For more information, see specifying first and next extent size in the chapter on managing dbspaces in the IBM Informix Administrator's Guide.
-k pagesize	Indicates in kilobytes, the non-default page size for the new dbspace. For systems with sufficient storage, performance advantages of a larger page size can include the following: Reduced depth of B-tree indexes, even for smaller index keys You can group on the same page long rows that currently span multiple pages of the default page size Checkpoint time is typically reduced with larger pages You can define a different page size for temporary tables, so that they have a separate buffer pool.	Restrictions: The page size must be between 2KB and 16KB and must be a multiple of the default page size. For example, if the default page size is 2KB, then pagesize can be 2, 4, 6, 8, 10, 12, 14, or 16. If the default page size is 4KB (Windows), then pagesize can be 4, 8, 12, or 16. References: For more information, see creating a dbspace with a non-default page size in the chapter on managing disk space in the IBM Informix Administrator's Guide.
-m pathname offset	Specifies an optional pathname and offset to the chunk that mirrors the initial chunk of the new dbspace Also see the entries for -p pathname and -o offset in this table.	References: For more information, see creating a dbspace in the chapter on managing disk space in the IBM Informix Administrator's Guide.
-o offset	Indicates, in kilobytes, the offset into the disk partition or into the device to reach the initial chunk of the new dbspace	Restrictions: Unsigned integer. The starting offset must be equal to or greater than 0. The starting offset plus the chunk size cannot exceed the maximum chunk size. The offset must be a multiple of the page size. The maximum offset is 2 or 4 gigabytes, depending on the platform. References: For more information, see allocating raw disk space, in the chapter on managing disk space in the IBM Informix Administrator's Guide.
-p pathname	Indicates the disk partition or device of the initial chunk of the dbspace that you are creating	Additional Information: The chunk must be an existing unbuffered device or buffered file. When you specify a pathname, you can use either a full pathname or a relative pathname. However, if you use a relative pathname, it must be relative to the directory that was the current directory when you initialized the database server. UNIX example (unbuffered device): `/dev/rdsk/c0t3d0s4` UNIX example (buffered device): `/ix/ids9.2/db1chunk`Windows example:`c:\Ifmxdata\ol_icecream\mychunk1.dat` References: For pathname syntax, see your operating-system documentation.
-s size	Indicates, in kilobytes, the size of the initial chunk of the new dbspace	Restrictions: Unsigned integer. The size must be equal to or greater than 1000 kilobytes and a multiple of the page size. The starting offset plus the chunk size cannot exceed the maximum chunk size. The maximum chunk size is 2 or 4 terabytes, depending on the platform.
-t	Creates a temporary dbspace for storage of temporary tables	Restrictions: You cannot mirror a temporary dbspace. You cannot specify the first and next extent sizes for the tblspace tblspace of a temporary dbspace. You cannot specify a non-default page size for a temporary dbspace. References: For more information, see temporary dbspaces, in the chapter on data storage, and creating a temporary dbspace, in the chapter on managing disk space in the IBM Informix Administrator's Guide.