How (not) to Lose How (not) to Lose Your AudienceYour Audience

Chris Lawson

Avoiding Big BlundersAvoiding Big Blunders

What’s the Issue?What’s the Issue?

• Really smart people often do really poor presentations.

• Sometimes even the featured speaker falls into this trap.

• This makes it tough for the audience to learn new ideas.

• It also wastes time.

Why Should I Care?Why Should I Care?

• Your presentation affects how people think about you.

• Fair or not, you gain or lose credibility• A great talk will be remembered for

years.• An unprepared speaker will likely not

be invited back. • Your ideas will be forgotten.• Not the best use of time.

The Good News The Good News

• Great presentations have little to do with your actual speaking ability.

• Most of it has to do with preparation.• Preparation can be time-consuming,

but the Payoff is huge.

THIS IS HOW YOUR LISTENERS WILL REACT

TO A GOOD PRESENTATION

BUT--YOU CAN’T WIN ‘EM ALLBUT--YOU CAN’T WIN ‘EM ALL

Photo courtesy of: “Guy sleeping behind obama at graduation"

2 Points to Remember 2 Points to Remember

Great speakers aren’t the smartest; they are the best prepared.

Consider what the audience will see

Blunder # 1Blunder # 1

Failing to check-out room & equipment

How Can I Tell I’m How Can I Tell I’m Losing the Audience? Losing the Audience?

Here are some easy ways to see you’re “losing it.”

How Can I Tell I’m How Can I Tell I’m Losing the Audience? Losing the Audience?

It may take keen skill to spot when you’re beginning to fade . . .

These Guys Need HelpThese Guys Need Help

How Rude!How Rude!

CASE STUDY:CASE STUDY:

How Can I Tell I’m How Can I Tell I’m Losing the Audience? Losing the Audience?

Be Alert to Subtle SignsBe Alert to Subtle SignsPhase 1: BoredomPhase 1: Boredom

Note Glazed Eyes

Do I get 17 or 18 weeks vacation?

Watch for Subtle SignsWatch for Subtle SignsPhase 2: RestlessnessPhase 2: Restlessness

Vacant stare

I didn’t know we DBAs were so

boring …

Watch for Subtle SignsWatch for Subtle SignsPhase 3: Loss of ConsciousnessPhase 3: Loss of Consciousness

Not very alert, beginning to drool

Watch for Subtle SignsWatch for Subtle SignsPhase 4: Coma (or death)Phase 4: Coma (or death)

No pulse

Blunder # 2Blunder # 2The “Cram” MethodThe “Cram” Method

Show slides with so much information no one can possibly comprehend it.

Corollary: Try to impress your audience—the

more information the better!

ResultsResultsA B C D E

0.78799174 0.87677244 0.99348605 0.23781547 0.244375260.24910355 0.79708654 0.39825661 0.4894876 0.220794560.65729261 0.46901063 0.36471191 0.04697233 0.634680590.48205396 0.52657506 0.70503426 0.35280176 0.409353130.46328137 0.0774365 0.71517444 0.9394662 0.468436380.09762717 0.70884867 0.81407539 0.24571711 0.724978190.00773315 0.39906447 0.42344939 0.90776976 0.222090060.15857663 0.4181197 0.56488165 0.91405841 0.35783490.59242455 0.17894389 0.61926672 0.02978346 0.507891720.41285757 0.71470398 0.31906988 0.79658426 0.21587647

0.8855586 0.46534556 0.3701164 0.12452538 0.334154970.28231467 0.17509894 0.85801024 0.72984635 0.947312380.82370951 0.03235362 0.95622299 0.27726297 0.766198790.86245578 0.21094811 0.93272287 0.48265505 0.049606460.38953201 0.3665743 0.33754918 0.28178635 0.396370090.80522838 0.63509032 0.43333321 0.97677807 0.961981720.35928212 0.14878634 0.44201417 0.23251612 0.833751540.72099806 0.75212293 0.81061259 0.23756284 0.485189960.13329065 0.31602317 0.87489249 0.5304632 0.26191565

0.2588109 0.89039838 0.81380512 0.59139955 0.484887590.99314419 0.34635186 0.73292414 0.25933239 0.292304910.88041055 0.11473455 0.01934078 0.15717245 0.937806760.72332226 0.80195173 0.1792961 0.07832254 0.411545790.95925002 0.41696749 0.24905812 0.2111233 0.002565360.00580885 0.65322119 0.49666074 0.91641276 0.405732750.26004883 0.3010126 0.45604195 0.99935168 0.91271048

0.1508427 0.84418604 0.96241158 0.05548096 0.940931540.63750743 0.08979734 0.11100042 0.34646613 0.099945330.17176871 0.85518113 0.94522781 0.29368901 0.774441610.15186964 0.53105474 0.69991523 0.07876247 0.00239780.72306385 0.73755246 0.71402806 0.68090612 0.760156360.42140074 0.39036871 0.02247591 0.94725973 0.70692042

• You havelots of coolresults– No one can

read this– No one can

understand this

• Graphs areyour friend…

Fastest Database - TPC-H Fastest Database - TPC-H

Size Database Hardware CPU/OS Cost

300G Oracle 10g HP/Proliant 8/RHEL4 524K

1T Oracle 10g HP/Superdome 64/HP UX 4.0M

3T Oracle 10g Sun/E25K 72/Solaris 5.8M

10T Oracle 10g Sun/E25K 72/Solaris 5.8M

“The performance metric reported by TPC-H is called the TPC-H Composite Query-per-Hour Performance Metric(QphH@Size). The TPC Benchmark™H (TPC-H) is a decision support benchmark. It consists of a suite of business oriented ad-hoc queries and concurrent data modifications. The queries and the data populating the database have been chosen to have broad industry-wide relevance. This benchmark illustrates decision support systems that examine large volumes of data, execute queries with a high degree of complexity, and give answers to critical business questions.”

Source: www.tpc.org (As of April 19, 2006)

Some Actual SlidesSome Actual Slides

I am not joking—the following are real slides from recent speakers

Do crosstab from RC_BACKUP_PIECE view.Make anything before 4PM part of previous overnight

run: CREATE OR REPLACE VIEW ucsc_bkup_trend_insert_vw (...column aliases...) AS SELECT CASE WHEN to_char(p.START_TIME,'HH24') < 16 THEN trunc(p.START_TIME - 1) ELSE trunc(p.START_TIME) END AS bkup_date, sdl.SERVER_NAME, d.name, p.device_type, nvl(max(CASE WHEN backup_type = 'D‘ THEN p.ELAPSED_SECONDS END),0) AS LVL0_secs,

nvl(max(CASE WHEN backup_type = 'I' THEN p.ELAPSED_SECONDS END),0) AS LVL1_secs,nvl(max(CASE WHEN backup_type = 'L' THEN p.ELAPSED_SECONDS END),0) AS ARCH_secs,nvl(max(CASE WHEN backup_type = 'D' THEN p.BYTES END),0) AS LVL0_bytes,nvl(max(CASE WHEN backup_type = 'I' THEN p.BYTES END),0) AS LVL1_bytes,nvl(max(CASE WHEN backup_type = 'L' THEN p.BYTES END),0) AS ARCH_bytes,

p.START_TIME, p.COMPLETION_TIMEFROM rc_backup_piece p, rc_database d, ucsc_server_db_list sdl

[...]

Runtime TrendsRuntime Trends

Identifying Identifying Granules of Parallelism during Granules of Parallelism during scans in the planscans in the plan

Metadata Reporting: Metadata Reporting: Compression RatioCompression Ratio

• COMPRESSION_RATIO column is in 10 _summary and _details views, but these are “primarily intended to be used internally by Enterprise Manager.”Before finding that caveat, I had found results to not trust RC_BACKUP_SET_DETAILS --- good to avoid. In following chart, (10.2.0.2 for testing), Input Bytes is same for Level 0 and 1, so calc is from total DB used space.Level 1 ratio is distorted.

• The BDF table in RC_BACKUP_DATAFILE view knows about Block Change Tracking, and has count of blocks scanned, so a better ratio could be calculated.

““Please Take this Survey”Please Take this Survey”

Keynote Speaker SlideKeynote Speaker Slide

•Twitter.com•Amazon EC2•Cuil.com•Apple iStore 2008•Google Gmail•WolframAlpha

Company XYZ Keynote presentation Oct, 23, 2009

What do You Think of this?What do You Think of this?

• The fastest execution plan usually is the one that touches the fewest rows, and this, in turn, is the one that discards the fewest rows, and that discards those rows that must be discarded the earliest, before wasting work on unneeded joins. This usually starts with the best filter condition (the one reaching the smallest fraction of its table), and reaches every large table with the fastest path (usually a filter-column index for the first table and nested loops to a join-key index for the later large tables).

• The goal is normally a query that runs in minutes, at the most, without requiring parallel threads.

Reaction to Prior SlideReaction to Prior Slide

• I believe this person is inept.• This guy is trying to bamboozle me.• This presentation was thrown together• This is going to be really boring.• Is he going to read every line?

(Ans: Yes, he did.)• I’m not inviting this guy to my party.• My reaction: I left after 5 minutes.

• These reactions might mislead you, because . . .

The Lesson The Lesson

• In actuality, the author of the messy slide is a genuine performance expert.

• About 13 years ago, I learned a great tuning technique from his writings.

• I use his technique nearly every day.

Moral: His presentation worked against him

instead of attesting to his skill

Let’s Try a RedesignLet’s Try a Redesign

Here’s the Original . . .

Tips on Performance TuningTips on Performance Tuning

• The fastest execution plan usually is the one that touches the fewest rows, and this, in turn, is the one that discards the fewest rows, and that discards those rows that must be discarded the earliest, before wasting work on unneeded joins. This usually starts with the best filter condition (the one reaching the smallest fraction of its table), and reaches every large table with the fastest path (usually a filter-column index for the first table and nested loops to a join-key index for the later large tables).

• The goal is normally a query that runs in minutes, at the most, without requiring parallel threads.

Here’s the Redesign. . .

Tips on Performance Tuning Tips on Performance Tuning

For good execution plans touch as few rows as possible

1. Filter-out rows as early as possible

2. Start with the best filter condition

3. Optimize first--use parallelism last.

Let’s try an example.

Try Replacing lots of text Try Replacing lots of text with a Picture with a Picture

Example with Example with TextText

There was once a very small software company that had a small government contract. The founders had some good ideas, but not a lot of money. They were smart, but some of them didn’t even have college degrees. To make things worse, some of them were sort of nerdy, and were not too good at social skills. Some of them even wore “pocket protectors” and put lots of felt-tip pens in their pockets. Nevertheless, they struggled, worked hard, and made lots of money. Today the founders are very famous and rich. If you work hard, you too can be like them.

Do you recognize any of these guys . . . ?

Example with Example with PicturePicture

Oracle CorporationOracle CorporationOne-year AnniversaryOne-year Anniversary

Ed Oates, Bruce Scott, Bob Miner, and Larry Ellison

Blunder # 3Blunder # 3Dull, Boring MonotoneDull, Boring Monotone

Blunder # 4Blunder # 4

Make slides that cannot be read

Corollary: Use colors that are scary

Chilean ExportsChilean Exports• Fresh fruit leads Chile's export mix - Chile emerges as major supplier of

fresh fruit to world market due to ample natural resources, consumer demand for fresh fruit during winter season in U.S. and Europe, and incentives in agricultural policies of Chilean government, encouraging trend toward diversification of exports and development of nontraditional crops - U.S. Dept. of Agriculture, Economic Research Service Report

• Chile is among the developing economies taking advantage of these trends, pursuing a free market economy. This has allowed for diversification through the expansion of fruit production for export, especially to the U.S. and Western Europe. Chile has successfully diversified its agricultural sector to the extent that it is now a major fruit exporting nation. Many countries view Chile's diversification of agriculture as a model to be followed.

• Meanwhile, the U.S. remains the largest single market for Chile's fruit exports. However, increasing demand from the EC and Central and East European countries combined may eventually surpass exports to the U.S., spurring further growth in Chile's exports.

• If you’ve read this far, your eyes probably hurt and you’ve been reading this tedious long-winded text instead of listening to me. I’m insulted- can’t you see I’m doing a presentation up here? Look at me! Congratulations, however, on having such good eyesight.

Do You Remember Do You Remember this Point? this Point?

Consider what the audience will see

At Vision-Loss ConferenceAt Vision-Loss Conference

Speaker showed complex slide with small font, and asked,

“Can everybody see this okay?”

Have mercy on the poor folks trying to read . . .

Beginner MotorcyclesBeginner Motorcycles• My personal

favorite: the Suzuki Savage

• Light weight (~380lbs)

• Adequate power (650cc engine)

• Low seat height fits most riders

Mommy, my eyes are Mommy, my eyes are burning!burning!

• Can you look at this for 45 minutes?• Colors look different on every LCD

projector• Colors look different between

transparencies and projector

• If printing slides, save ink by choosing white background.

Mommy, my eyes are Mommy, my eyes are burning!burning!

Use PowerPointUse PowerPoint• Dazzle them with 256,000,000 colors!Dazzle them with 256,000,000 colors!• Cliché templates!Cliché templates!• Sound Effects!Sound Effects!• Annoying transitions!Annoying transitions!• Import video and animations that Import video and animations that

won't workwon't work• Put an annoying header and footer on Put an annoying header and footer on

every slideevery slide

Terrible Presentations 16/17

Summary: Summary: Big BlundersBig Blunders

1. Failure to prepare the room2. Overly complex slides3. Monotone presentation4. Unreadable slides

2 Points to Remember 2 Points to Remember

Great speakers are the best prepared speakers

Consider what the audience will see

For Further Reading on For Further Reading on What You What You ShouldShould do do

Rich NiemiecConsistently rated #1 presenter

See: Giving Winning PresentationsCollaborate 2009