SQL Tuning [Electronic resources]

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data

amount produced by application 2nd 3rd

denormalized

normalized

path to [See data access; execution plans]

transferring between applications

data access

caching and

indexes and 2nd 3rd

joins and

reasons to understand

selectivity

single-table access paths

tables and 2nd 3rd 4th 5th

data type conversions, indexes enabled and disabled by 2nd

database [See also caching; indexes; tables]

adding merged join and filter indexes to

adding missing indexes to

adding table to, for joins with hidden join filters

altering, example of

combining tables in

for exact one-to-one joins

for joins with hidden join filters

separating tables in, for one-to-one join to small subset

database blocks [See blocks]

database vendors

SQL tuning and 2nd

tools for execution plans provided by 2nd

date-type columns in indexes

DB2

COALESCE() function

execution plans

complex

controlling

displaying 2nd 3rd

interpreting

multipart

nonrobust

robust

tables for execution-plan data

modifying queries with

nested views created on the fly

null conditions in indexed columns

optimization levels

type conversions with

updating statistics with

db2exfmt tool

DBMS_STATS package

DELETE command

deletes in index, performance effects of

denormalization

in cyclic join graph cases 2nd

when to use

denormalized data [See also normalized data]2nd

detail join ratio 2nd 3rd

close to 1.0, affecting optimum execution plan

example of

in query diagrams

large, affecting optimum execution plan 2nd

less than 1.0

affecting optimum execution plan

caused by query diagram with multiple roots

detail table

developers, tuning their own SQL

diagrams [See query diagrams]

directed graph 2nd [See also query diagrams]

disconnected query diagrams

distributed filters 2nd

driving table 2nd

choosing 2nd 3rd

forcing selection of