A
multiplex configuration with shared temporary storage can use the IQ_SHARED_TEMP dbspace as
a shared system temporary store instead of requiring a separate local store for each
secondary server. The shared system temporary store simplifies multiplex configuration,
improves performance, and supports distributed query processing.
On multiplex systems:
- When you set the logical server policy option TEMP_DATA_IN_SHARED_TEMP ON,
SAP Sybase IQ creates all temporary objects on the
IQ_SHARED_TEMP dbspace. You must restart secondary nodes after setting this
option or after adding a read-write file to the shared temporary store. (If the
shared temporary store contains no read-write file, or if you do not restart
secondary nodes, data instead writes to IQ_SYSTEM_TEMP.)
- Temporary user objects (such as tables or table indexes) that you create using
the IN IQ_SYSTEM_TEMP clause go in either IQ_SYSTEM_TEMP or
IQ_SHARED_TEMP, depending on the value of the logical server option TEMP_DATA_IN_SHARED_TEMP:
- If TEMP_DATA_IN_SHARED_TEMP is 'OFF', objects go in IQ_SYSTEM_TEMP.
- If TEMP_DATA_IN_SHARED_TEMP is set 'ON', objects go in
IQ_SHARED_TEMP.
SAP Sybase IQ does not support creating temporary user
objects using the IN IQ_SHARED_TEMP clause.
- The WITH STOP SERVER clause automatically shuts down all
servers in the logical server. These statements support WITH STOP
SERVER:
- ALTER LOGICAL SERVER
- ALTER LS POLICY
- CREATE LOGICAL SERVER
- DROP LOGICAL SERVER
- If you use ALTER LS POLICY ... WITH STOP SERVER to change the
TEMP_DATA_IN_SHARED_TEMP option 'ON|OFF', all servers in that logical server
shut down automatically. You must restart the servers to force the logical
server to place temporary data in the store specified by the
TEMP_DATA_IN_SHARED_TEMP option.
- If you use ALTER LS POLICY to set TEMP_DATA_IN_SHARED_TEMP
'OFF', the logical server starts placing temporary data in the SYSTEM temporary
area after the next normal server startup.
- You can also change the TEMP_DATA_IN_SHARED_TEMP value indirectly using
CREATE LOGICAL SERVER, ALTER LOGICAL
SERVER, or DROP LOGICAL SERVER statements and
the WITH STOP SERVER clause.