Altering a Cache Group to Change the AUTOREFRESH Mode, Interval or State
After creating a cache group with autorefresh, you can use ALTER CACHE
GROUP
statement to change autorefresh mode, interval or state.
-
In TimesTen Classic, you can change the cache group's autorefresh mode, interval or state.
-
In TimesTen Scaleout, you can only change the cache group's autorefresh state.
You cannot use ALTER CACHE GROUP
to instantiate automatic refresh for a cache group that was originally created without autorefresh defined.
If you change a cache group's autorefresh state to OFF
or drop a cache group that has an autorefresh operation in progress:
-
The autorefresh operation stops if the setting of the
LockWait
connection attribute is greater than 0. TheALTER CACHE GROUP
orDROP CACHE GROUP
statement preempts the autorefresh operation. -
The autorefresh operation continues if the
LockWait
connection attribute is set to 0. TheALTER CACHE GROUP
orDROP CACHE GROUP
statement is blocked until the autorefresh operation completes or the statement fails with a lock timeout error.
The following example alters the autorefresh attributes of a cache group in TimesTen Classic. These statements change the autorefresh mode, interval and state of the customer_orders
cache group:
ALTER CACHE GROUP customer_orders SET AUTOREFRESH MODE FULL; ALTER CACHE GROUP customer_orders SET AUTOREFRESH INTERVAL 30 SECONDS; ALTER CACHE GROUP customer_orders SET AUTOREFRESH STATE ON;
TimesTen returns asynchronously after executing the ALTER CACHE GROUP
statement. However, there may be a delay for the cache agent to implement the change for the new state, mode or interval.