Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Which Indexes Should I Create?
Search
Chris
July 01, 2020
Technology
0
150
Which Indexes Should I Create?
An overview of how to decide which indexes to create on your database tables
Chris
July 01, 2020
Tweet
Share
More Decks by Chris
See All by Chris
Create reusable SQL expressions with SQL macros
chrissaxon
0
79
All About Insert
chrissaxon
0
160
Generating days between two dates
chrissaxon
0
180
Converting rows to columns and back again
chrissaxon
0
190
Finding the Longest Common Substring & Gestalt Pattern Matching with SQL & PL/SQL
chrissaxon
0
560
DBA Masterclass Application Tuning
chrissaxon
0
3.1k
A Preview of Oracle Database 20c PLSQL Enhancements
chrissaxon
0
230
Why Is the Optimizer Estimating the Wrong Number of Rows?
chrissaxon
0
98
How to Read an Execution Plan
chrissaxon
0
130
Other Decks in Technology
See All in Technology
SDカードフォレンジック
su3158
1
640
Bazel for Ruby (RubyKaigi 2025)
p0deje
0
120
PagerDuty×ポストモーテムで築く障害対応文化/Building a culture of incident response with PagerDuty and postmortems
aeonpeople
2
410
【Oracle Cloud ウェビナー】ご希望のクラウドでOracle Databaseを実行〜マルチクラウド・ソリューション徹底解説〜
oracle4engineer
PRO
1
110
テストって楽しい!開発を加速させるテストの魅力 / Testing is Fun! The Fascinating of Testing to Accelerate Development
aiandrox
0
110
Notion x ポストモーテムで広げる組織の学び / Notion x Postmortem
isaoshimizu
1
120
Cross Data Platforms Meetup LT 20250422
tarotaro0129
1
760
4/17/25 - CIJUG - Java Meets AI: Build LLM-Powered Apps with LangChain4j (part 2)
edeandrea
PRO
0
130
持続可能なドキュメント運用のリアル: 1年間の成果とこれから
akitok_
1
220
Mastraに入門してみた ~AWS CDKを添えて~
tsukuboshi
0
320
ブラウザのレガシー・独自機能を愛でる-Firefoxの脆弱性4選- / Browser Crash Club #1
masatokinugawa
1
510
Рекомендации с нуля: как мы в Lamoda превратили главную страницу в ключевую точку входа для персонализированного шоппинга. Данил Комаров, Data Scientist, Lamoda Tech
lamodatech
0
790
Featured
See All Featured
Building a Modern Day E-commerce SEO Strategy
aleyda
40
7.2k
CSS Pre-Processors: Stylus, Less & Sass
bermonpainter
357
30k
Gamification - CAS2011
davidbonilla
81
5.2k
Imperfection Machines: The Place of Print at Facebook
scottboms
267
13k
The Straight Up "How To Draw Better" Workshop
denniskardys
232
140k
Raft: Consensus for Rubyists
vanstee
137
6.9k
CoffeeScript is Beautiful & I Never Want to Write Plain JavaScript Again
sstephenson
160
15k
Six Lessons from altMBA
skipperchong
27
3.7k
Automating Front-end Workflow
addyosmani
1369
200k
A better future with KSS
kneath
239
17k
For a Future-Friendly Web
brad_frost
176
9.7k
Optimizing for Happiness
mojombo
377
70k
Transcript
Your SQL Office Hours begins soon… Which Indexes Should I
Create? Chris Saxon @ChrisRSaxon & @SQLDaily https://www.youtube.com/c/TheMagicofSQL https://blogs.oracle.com/sql
The following is intended to outline our general product direction.
It is intended for information purposes only, and may not be incorporated into any contract. It is not a commitment to deliver any material, code, or functionality, and should not be relied upon in making purchasing decisions. The development, release, timing, and pricing of any features or functionality described for Oracle’s products may change and remains at the sole discretion of Oracle Corporation. Statements in this presentation relating to Oracle’s future plans, expectations, beliefs, intentions and prospects are “forward-looking statements” and are subject to material risks and uncertainties. A detailed discussion of these factors and other risks that affect our business is contained in Oracle’s Securities and Exchange Commission (SEC) filings, including our most recent reports on Form 10-K and Form 10-Q under the heading “Risk Factors.” These filings are available on the SEC’s website or on Oracle’s website at http://www.oracle.com/investor. All information in this presentation is current as of September 2020 and Oracle undertakes no duty to update any statement in light of new information or future events. Safe Harbor Copyright © 2020 Oracle and/or its affiliates.
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| Welcome to Ask TOM Office Hours!
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| DEMO
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| Index Columns i1 customer_id i2 customer_id, order_datetime i3 order_datetime i4 order_status i5 store_id, order_status i6 order_status, customer_id
How does the database search indexes?
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| 101, rowid 102, rowid 102, rowid … 110, rowid 1 .. 100 101 .. 200 … 901 .. 1000 create index brick_weight_i on bricks ( weight ); 901 .. 910 911 .. 920 … 991 .. 1000 101 .. 110 111 .. 120 … 191 .. 200 1 .. 10 11 .. 20 … 91 .. 100 991, rowid 993, rowid 994, rowid … 1000, rowid 11, rowid 12, rowid 12, rowid … 20, rowid 1, rowid 2, rowid 4, rowid … 10, rowid 901, rowid 903, rowid 904, rowid … 910, rowid … … 91, rowid 92, rowid 95, rowid … 100, rowid …
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| 101, rowid 102, rowid 102, rowid … 110, rowid 1 .. 100 101 .. 200 … 901 .. 1000 create index brick_weight_i on bricks ( weight ); 901 .. 910 911 .. 920 … 991 .. 1000 101 .. 110 111 .. 120 … 191 .. 200 1 .. 10 11 .. 20 … 91 .. 100 991, rowid 993, rowid 994, rowid … 1000, rowid 11, rowid 12, rowid 12, rowid … 20, rowid 1, rowid 2, rowid 4, rowid … 10, rowid 901, rowid 903, rowid 904, rowid … 910, rowid … … 91, rowid 92, rowid 95, rowid … 100, rowid weight between 90 and 110; …
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| blue green red yellow red, cube red, cube red, cuboid red, star yellow, cube yellow, cuboid yellow, cuboid yellow, star create index brick_colour_shape_i on bricks ( colour, shape ); green, cube green, cube green, cuboid green, star blue, cube blue, cube blue, cuboid blue, cuboid colour = 'red';
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| blue green red yellow red, cube red, cube red, cuboid red, star yellow, cube yellow, cuboid yellow, cuboid yellow, star create index brick_colour_shape_i on bricks ( colour, shape ); green, cube green, cube green, cuboid green, star blue, cube blue, cube blue, cuboid blue, cuboid shape = 'cube';
blogs.oracle.com/sql www.youtube.com/c/TheMagicOfSQL @ChrisRSaxon Leading columns in where
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| Where clause Index columns customer_id = … customer_id customer_id = … order_datetime > … customer_id, order_datetime order_status = … store_id = … order_status, store_id order_status = … customer_id = … order_status, customer_id
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| Where clause Index columns customer_id = … customer_id customer_id = … order_datetime = … customer_id, order_datetime order_status = … store_id = … order_status, store_id order_status = … customer_id = … order_status, customer_id
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| Where clause Index columns customer_id = … customer_id customer_id = … order_datetime = … customer_id, order_datetime order_status = … store_id = … order_status, store_id order_status = … customer_id = … order_status, customer_id
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| Where clause Index columns customer_id = … customer_id customer_id = … order_datetime = … customer_id, order_datetime order_status = … store_id = … order_status, store_id order_status = … customer_id = … order_status, customer_id
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| Where clause Index columns customer_id = … customer_id customer_id = … order_datetime = … customer_id, order_datetime order_status = … store_id = … order_status, store_id order_status = … customer_id = … order_status, customer_id
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| Why not create them all? Storage is cheap!
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| PROD SBY DR STAGE DEV DEV DEV DEV
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| Storage is still cheap!
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| PROD 10Tb
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| PROD 10Tb 128Gb >>
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| How can the data stay cached?
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| TRANSACTIONS
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| TRANSACTIONS customer_id = … status = 'OPEN' customer_id = … trans_date > …
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| TRANSACTIONS customer_id = … status = 'OPEN' customer_id = … trans_date > …
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| TRANSACTIONS customer_id = … status = 'OPEN' customer_id = … trans_date > …
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| The tables & indexes fit in
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| customer_id = … Where
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| customer_id = … customer_id, order_datetime customer_id, order_status Where Indexes
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| customer_id = … customer_id, order_datetime store_id, order_status customer_id, order_status Where Indexes store_id = … order_datetime > … order_status = …
blogs.oracle.com/sql www.youtube.com/c/TheMagicOfSQL @ChrisRSaxon Create few indexes
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| customer_id = … status = …
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
|
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| ( status, customer_id ) CANCELLED, 1 CANCELLED, 2 CANCELLED, 3 CANCELLED, 4 … COMPLETE, 1 COMPLETE, 2 COMPLETE, 3 COMPLETE, 4 … OPEN, 1 OPEN, 2 OPEN, 3 OPEN, 4 … ( status, customer_id ) 0:CANCELLED 0, 1 0, 2 0, 3 0, 4… 1:COMPLETE, 1, 1 1, 2 1, 3 1, 4… 2: OPEN 2, 1 2, 2 2, 3 2, 4…
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| ( status, customer_id ) CANCELLED, 1 CANCELLED, 2 CANCELLED, 3 CANCELLED, 4 … COMPLETE, 1 COMPLETE, 2 COMPLETE, 3 COMPLETE, 4 … OPEN, 1 OPEN, 2 OPEN, 3 OPEN, 4 … ( status, customer_id ) 0:CANCELLED 0, 1 0, 2 0, 3 0, 4… 1:COMPLETE, 1, 1 1, 2 1, 3 1, 4… 2: OPEN 2, 1 2, 2 2, 3 2, 4…
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| ( status, customer_id ) CANCELLED, 1 CANCELLED, 2 CANCELLED, 3 CANCELLED, 4 … COMPLETE, 1 COMPLETE, 2 COMPLETE, 3 COMPLETE, 4 … OPEN, 1 OPEN, 2 OPEN, 3 OPEN, 4 … ( status, customer_id ) 0:CANCELLED 0, 1 0, 2 0, 3 0, 4… 1:COMPLETE 1, 1 1, 2 1, 3 1, 4… 2: OPEN 2, 1 2, 2 2, 3 2, 4… compress 1
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| ( customer_id, status ) 0: 1 0, CANCELLED 0, COMPLETE 0, OPEN … 1: 2 1, CANCELLED 1, COMPLETE 1, OPEN … 2: 3 2, CANCELLED 2, COMPLETE 2, OPEN …
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| ( status, customer_id ) 0:CANCELLED 0, 2141fd1c-8292-4726-b3fe-a980a2c8a430 0, 57f802ea-cff1-4d2d-b78b-ef964f5b2dd5 0, e79d5a65-5552-4eca-a945-6ad2dbb9359b 0, 5dbdc286-2f22-4ef1-a497-3c70d334c94b… 1:COMPLETE 1, 2141fd1c-8292-4726-b3fe-a980a2c8a430 1, 57f802ea-cff1-4d2d-b78b-ef964f5b2dd5 1, e79d5a65-5552-4eca-a945-6ad2dbb9359b 1, 5dbdc286-2f22-4ef1-a497-3c70d334c94b… 2: OPEN 2, 2141fd1c-8292-4726-b3fe-a980a2c8a430 2, 57f802ea-cff1-4d2d-b78b-ef964f5b2dd5 2, e79d5a65-5552-4eca-a945-6ad2dbb9359b 2, 5dbdc286-2f22-4ef1-a497-3c70d334c94b…
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| ( customer_id, status ) 0: 2141fd1c-8292-4726-b3fe-a980a2c8a430 0, CANCELLED 0, COMPLETE 0, OPEN … 1: 57f802ea-cff1-4d2d-b78b-ef964f5b2dd5 1, CANCELLED 1, COMPLETE 1, OPEN … 2: e79d5a65-5552-4eca-a945-6ad2dbb9359b 2, CANCELLED 2, COMPLETE 2, OPEN …
blogs.oracle.com/sql www.youtube.com/c/TheMagicOfSQL @ChrisRSaxon Compresible columns first
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| DEMO
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| • Keep # indexes small • ( = col, > col, select_order_by_cols ) • Compresiblecols 1st • Automatic Indexing solve 1 & 2 for you! Summary
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| Richard Foote's Blog https://richardfoote.wordpress.com/ Further Reading
Copyright © 2020, Oracle and/or its affiliates. All rights reserved.
| asktom.oracle.com #MakeDataGreatAgain Ryan McGuire / Gratisography