Abstract: A memory block that includes a physical storage page holding data of a data storage application in a page buffer can be cached in a page buffer upon the memory block being designated for a change in status from a used status to a shadow status. Upon occurrence of a trigger event, all pages stored in the page buffer can be processed in a first batch process that can include converting each of the pages in the page buffer from the used status to the shadow status and emptying the page buffer. Upon receiving a call to free the pages in the page buffer from the shadow status to a free status without the trigger event occurring, the pages in the page buffer can be converted from the used status directly to the free status in a second batch process. Related methods, systems, and articles of manufacture are also disclosed.

Abstract: A database system may provide determination of statistics for a field of a database table. The determination may include determination of whether the field of the table is associated with a check table, and, if the field of the table is associated with a check table, determination of a number of distinct values of the field in the table based on a number of distinct values of the field in the check table.