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[SYMBOL]
[A]
[B]
[C]
[D]
[E]
[F]
[G]
[H]
[I]
[J]
[K]
[L]
[M]
[N]
[O]
[P]
[Q]
[R]
[S]
[T]
[U]
[V]
[W]
parallel execution plans
2nd
parentheses (()) in FROM clause for DB2
surrounding ordered list of items
partitioned tables
path to data
[See data access; execution plans] performance
[See also SQL tuning] adding indexes affecting
caching scheme affecting
calculations performed on data affecting
compared to throughput
database operations affecting
logical I/Os and
physical layout of table rows and
SQL as factor in
physical I/O
caching used to minimize
performance of
PLAN_TABLE table
plus sign (+) in comment
in join clause
post-group filtering, not included in query diagram
post-read filter
2nd
3rd
primary keys
indicated by arrows in query diagrams
missing from join
problem cases
[See also exercises; SQL tuning] abnormal outer joins
all tables relatively small except one
Cartesian products between first set of rows
corner-case problems
2nd
3rd
4th
cyclic join graphs
detail join ratios close to 1.0
detail join ratios less than 1.0
2nd
disconnected query diagrams
filter ratios close to each other
join ratios less than 1.0
joining to the same table twice
joins with no primary key
large detail join ratios
large rowcount returned by query
master join ratios less than 1.0
2nd
middleware processes handling too many rows
one-to-one joins
2nd
outer joins to views
performance and throughput problems
queries aggregating too many rows
2nd
3rd
queries repeated a large number of times
2nd
queries returning too many rows
2nd
queries running slowly even when returning few rows
2nd
queries with set operations
queries with subqueries
2nd
queries with views
2nd
query diagrams with multiple roots
redundant reads in view-using queries
unfiltered joins
unnecessary nodes and joins
programmers, tuning their own SQL
pure logical I/O, caching used for
purge eldest pattern
purge, not by age pattern
PUSH_SUBQ hint
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