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Figure 10-7.
Sample explain plan output
An explain plan also identifies micro-partition pruning through the
GlobalStats
and
TableScan
operators. You can also see the table aliases declared under the alias column;
I will discuss aliases later. Figure 10-8 shows the effect of micro-partition pruning for the
table
PART_BASELINE
. Note that
partitionsAssigned
is not an absolute value subject to
later execution optimization.
Figure 10-8.
Explain plan micro-partition pruning
GET_QUERY_OPERATOR_STATS
GET_QUERY_OPERATOR_STATS
returns query operator information for completed queries.
GET_QUERY_OPERATOR_STATS
is limited to queries executed in the past 14 days, which sets
the maximum timeframe for how frequently any automated monitoring solution can run
without missing information.
ChapTer 10
OpTimizing perfOrmanCe