List of terms specific to the thesis

This section lists a) terms specific to this thesis and b) terms used with a specific meaning. Compound terms based on these, and incorporating the concepts of average, minimum, maximum and difference (e.g. avgQS, minAS, ΔSTn,m) are not included here, but are explained in full where they first occur.

Appendix 6 is a glossary of general acronyms and terms.

list of specific acronyms

AS
access size.
NPA
number of partitions accessed used by a range query.
migprob
migration probability.
pcost
partitioning cost.
PS
partition size.
QS
query size.
STS
scan time saving.
WL
workload.
WLS
workload saving.
WW
wasted work.

glossary of terms

access size
the logical fraction of data accessed in a given dimension.
end effect
the breakdown in the assumption that range queries evenly reference the domain range. This breakdown occurs when the number of partitions is small.
migration cost
the cost of a single data migration between two partitions.
migration probability
the probability that an OLTP transaction will cause an update to a record which will require that record to migrate.
partitioning cost
the overall cost of partitioning a column.
query size
the fraction of records referenced by a range query in a given dimension.
scan time saving
defined as the cost of scanning the partitions in which required data resides minus the cost of scanning the data if there were no partitioning.
wasted work
amount of data accessed minus the required data. In a single dimension this is QS-AS.
workload
defined as the scan time plus partition costs.
workload saving
the total saving in workload that can be made by partitioning a file (= STS + pcost).