This section explains how you can use the option Sybase IQ provides to do disk striping, without using third-party software. If you already have a disk striping solution through third-party software and hardware, you should use that method instead. Disk striping can be enabled by specifying the STRIPING ON option to the CREATE DBSPACE command.
The syntax you use to change the default striping when creating a dbspace is:
SET OPTION "PUBLIC".DEFAULT_DISK_STRIPING = { ON | OFF }
The default for the DEFAULT_DISK_STRIPING option is ON for all platforms. When disk striping is ON, incoming data is spread across all dbspaces with space available. When disk striping is OFF, dbspaces (disk segments) are filled up from the front on the logical file, filling one disk segment at a time.
If you change the value of DEFAULT_DISK_STRIPING, it will affect all subsequent CREATE DBSPACE operations that do not specify a striping preference.
You can remove a file from a dbspace using the ALTER DBSPACE DROP command when disk striping is on. Before dropping the dbspace, however, you must relocate all of the data in the dbspace using the sp_iqemptyfile stored procedure. Because disk striping spreads data across multiple files, the sp_iqemptyfile process may require the relocation of many tables and indexes. Use the sp_iqdbspaceinfo and sp_iqdbspace stored procedures to determine which tables and indexes reside on a dbspace.
