I'd advise against a modify to merge. If you want to try something, just modify the table to reconstruct. Modify to merge is very log- intensive, and outside of certain specific cases I can't recommend it.
It's hard to say for sure when a btree needs modified; it's usually easier to just do it rather than trying to analyze it. (you can get into tools like "modify to table_debug" but by the time you have interpreted the output, your modify to reconstruct would be finished...) Karl On Aug 6, 2009, at 1:36 PM, Dave Marvin wrote: > Hello: > > > > A table of 24M records is keyed on a btree index of unique > values. Records are generally appended to this table. Records > are occasionally replaced (rather than modified) by deleting and > then appending similar or even identical data. Rarely are records > permanently deleted from the table. > > > > Will the btree index on this table benefit from a merge? How can I > tell? Are there graphical or tabular metrics that I can review to > show me the number of inactive (deleted) index values relative to > the entire index structure? Knowing how much the index will > shrink, and how long it takes to regenerate the btree index from > scratch, can I reliably guestimate how long the modify… to merge > will take? > > > > Cheers! > > Dave > > > > Dave Marvin > > Columbia Basin PIT Tag Information System > > Pacific States Marine Fisheries Commission > > dave.mar...@ptagis.org > > > > _______________________________________________ > Users mailing list > Users@lists.ingres.com > http://lists.ingres.com/mailman/listinfo/users _______________________________________________ Users mailing list Users@lists.ingres.com http://lists.ingres.com/mailman/listinfo/users
