SQL Tuning [Electronic resources] نسخه متنی

join execution methods

hash joins

forcing use of
2nd

in Oracle execution plan

in SQL Server execution plan

when to use
2nd
3rd
4th
5th

nested-loops joins

in DB2 execution plan

forcing use of
2nd

in Oracle execution plan

in SQL Server execution plan

when to use
2nd

sort-merge joins

in DB2 execution plan

in Oracle execution plan

when to use
2nd

join filters
2nd
3rd
4th

join key, merged with filter column in index

join order
[See also execution plans]

calculating cost of

choosing
2nd
3rd

controlling
2nd

disabling undesired join orders

enabling desired join order

for outer joins

join ratio
2nd
[See also detail join ratio; master join ratio]3rd

calculating

information about actual data provided by

less than 1.0
2nd
[See also join filters]

in query diagrams
2nd

referential integrity, effect on

shortcuts for
2nd

join skeleton (query skeleton)

joins
2nd

anti-join
2nd

Cartesian join
2nd

condition for

missing
2nd
3rd

not included in query diagrams

correlation join
2nd
3rd

cyclic
2nd

forcing order of
2nd

hash join
[See hash joins]

inner joins
2nd
3rd

many-to-one

missing

multipart join

nested-loops join
[See nested-loops joins]

one-to-many, unintended

one-to-one
2nd

order of
[See join order]

outer joins
[See outer joins]

in query diagrams
2nd

redundant joins

semi-join
2nd

sort-merge join
[See sort-merge joins]

unfiltered

unnecessary, in queries with views

without primary key