Hitachi

Hitachi Advanced Database Setup and Operation Guide


6.22.1 Estimating the increase in the amount of data that occurs when the adbmergechunk command is executed

When indexes are defined for a table designated for merge chunk processing, the amount of index data increases while the adbmergechunk command is being executed and when its execution is halted.

Therefore, when you execute the adbmergechunk command, add the amount of data needed to rebuild the index at the merge-target chunk to the values estimated in sections 5.8.3 Determining the number of storage pages for each B-tree index segment, 5.8.5 Determining the number of storage pages for each text index segment, and 5.8.6 Determining the number of segments for storing each range index. For the amount of data needed to rebuild an index, assume a value equivalent to the sum total of the amount of index data in the merge-target chunk.

For details about why the amount of index data increases during execution of the adbmergechunk command, see the note in (3) Using the adbmergechunk command to merge chunks under 11.4.9 Merging chunks (to reduce the number of chunks).