You specify the data type of a column when you create the table. For smart large objects, you specify CLOB, BLOB, or user-defined data types. As Figure 43 shows, to control the placement of smart large objects, you can use the IN sbspace option in the PUT clause of the CREATE TABLE statement.
Before you specify an sbspace in a PUT clause, you must first create the sbspace. For more information on how to create an sbspace with the onspaces -c -S command, see Adding a Chunk to a Dbspace or Blobspace. For more information on how to specify smart large object characteristics in the PUT clause, refer to the CREATE TABLE statement in the IBM Informix Guide to SQL: Syntax.
If you do not specify the PUT clause, the database server stores the smart large objects in the default sbspace that you specify in the SBSPACENAME configuration parameter. For more information on SBSPACENAME, refer to the configuration parameter chapter of the IBM Informix Dynamic Server Administrator's Reference.
An sbspace includes one or more chunks, as Figure 44 shows. When an sbspace contains more than one chunk, you cannot specify the chunk in which the data resides.
You can add more chunks at any time. It is a high-priority task of a database server administrator to monitor sbspace chunks for fullness and to anticipate the need to allocate more chunks to a sbspace. For more information on monitoring sbspaces, refer to your IBM Informix Dynamic Server Performance Guide.
The database server uses sbspaces to store table columns that contain smart large objects. The database server uses dbspaces to store the rest of the table columns.
You can mirror an sbspace to speed recovery in event of a media failure. For more information, refer to Mirroring.
For information on using onspaces to perform the following tasks, see Managing Disk Space.