The CURRENT REFRESH AGE special register specifies a timestamp duration value with a data type of DECIMAL(20,6). This duration is the maximum duration since a REFRESH TABLE statement has been processed on a REFRESH DEFERRED summary table such that the summary table can be used to optimize the processing of a query. If CURRENT REFRESH AGE has a value of 99 999 999 999 999 (ANY), and QUERY OPTIMIZATION class is 5 or more, REFRESH DEFERRED summary tables are considered to optimize the processing of a dynamic SQL query. A summary table with the REFRESH IMMEDIATE attribute and not in check pending state is assumed to have a refresh age of zero.
Its value can be changed by the SET CURRENT REFRESH AGE statement (see SET CURRENT REFRESH AGE). Summary tables defined with REFRESH DEFERRED are never considered by static embedded SQL queries.
The initial value of CURRENT REFRESH AGE is zero.