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Note

Please ensure you are using ANSI SQL for this task

ResultExpected result [tbl_output]:

Customer_Name

Order_ID

Order_Date

Order_Value

Aaron Bergman

CA-2017-140935

2017-11-10

563.94

Aaron Bergman

CA-2015-152905

2015-02-18

12.624

Aaron Hawkins

CA-2018-164000

2018-12-18

18.704

Aaron Hawkins

CA-2015-122070

2015-04-22

257.752

Aaron Smayling

CA-2018-101749

2018-10-03

171.288

Aaron Smayling

US-2015-150126

2015-07-27

65.78

Adam Bellavance

CA-2018-107174

2018-11-06

2595.388

Adam Bellavance

CA-2016-150511

2016-09-18

18.54

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Using the result from question 2 [tbl_output], please write a query that will return on the same row the:

  • Customer Name
  • First Order Value
  • Last Order Value
  • Percentage difference between the first and last orders

ResultExpectation:

Customer_Name

Latest_Value

Earliest_Value

Perc_Diff

Aaron Bergman

563.94

12.624

4367.20532319392

Aaron Hawkins

18.704

257.752

-92.7434122722617

Aaron Smayling

171.288

65.78

160.395256916996

Adam Bellavance

2595.388

18.54

13898.8565264293

...

First_Name

Last_Name

Order_Date

Order_ID

Chuck

Clark

2018-12-30

CA-2018-126221

Erica

SMITH

2018-12-30

CA-2018-115427

Jill

Matthias

2018-12-30

CA-2018-156720

Patrick

O'Donnell

2018-12-30

CA-2018-143259

Michael

Chen

2018-12-29

US-2018-102638

James

Galang

2018-12-29

CA-2018-118885

Katherine

hughes

2018-12-29

US-2018-158526

Ken

Brennan

2018-12-29

CA-2018-158673

Bruce

Stewart

2018-12-29

CA-2018-130631

Ben

Peterman

2018-12-29

CA-2018-146626

Christopher

Schild

2018-12-28

CA-2018-135111

Erica

Hernandez

2018-12-28

CA-2018-127516

Greg

Hansen

2018-12-28

CA-2018-136539

Harry

Marie

2018-12-28

CA-2018-129805

Kristen

Smith

2018-12-30

CA-2018-163979

Lori

Olson

2018-12-28

CA-2018-163860

Jason

Gross

2018-12-28

CA-2018-101322

Jennifer

smith

2018-12-30

CA-2018-164826

Pamela

Coakley

2018-12-28

US-2018-162068

Susan

SMITH

2018-12-28

CA-2018-122798

The above This table contains 1 trillion rows of data, and has indexes on the Last_Name and Order_Date columns.
The Last_Name field is  is case insensitive meaning some entries are in can be either UPPERCASE, some lowercase, and some or MiXed-mODecASe.

You are looking for all customers with the whose Last_Name of  is 'smith' , text (all cases). Text searches are case-sensitive meaning that searching in just one case, may not return the complete result. You all customers, and you are also only interested in orders made on 2018-12-30

An initial analysis of the data shows that of the 1 trillion rows, 2018-12-30 contains just 500,000 (five-hundred thousand) rows of data.

In order Which of these queries is the more efficient to fetch the required data, please can you identify which of these queries are the most efficient considering the performance enhancements. Explain why.

...

Query OrderExecution Order

Select

From

Join

Where

Group By

Having

Order By


Question 5b:

Please explain what What is Union is, and a and  Union All. Can you give ? How they differ? And can you provide an example of their use.

There are five types of join, can you name them and Please can you name the five join types, and provide an example of their use.


Tip
iconfalse

Question 6:

The This table below is a transaction stream log:

dbo.txn

Row_ID

Txn_ID

Account_ID

Txn_DateTime

Status

1

123abc

112233

2000-01-01 08:08:45

Initiated

2

895jkl

112233

2000-01-01 08:09:03

Initiated

3

747ghd

456789

2000-01-01 08:12:21

Initiated

4

123abc

112233

2000-01-01 08:13:15

In Process

5

696pol

456892

2000-01-01 08:14:37

Initiated

6

123abc

112233

2000-01-01 08:17:43

Successful

7

895ghd

784521

2000-01-01 08:22:51

Initiated

8

696pol

456892

2000-01-01 08:23:04

In Process

9

696pol

456892

2000-01-01 08:23:08

Failed

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Thinking about Tableau, you have a workbook connected to a data-source that is more than 3 .2 billion rows and 120 is around 180 columns wide.
This data needs to be refactored each day so the entirety of the table must be dropped and rebuilt in a job taking more than 12 hours each night.
As a result, Data this large is too much data to be loaded into an extract, and too much for Tableau Server to unpack into temp memory.

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Looking at this table:

Which of the following exprssions will be the these two calculations is the most performant in achieving the highlighted row?

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Note

The version 2020.2 changes to the Tableau data model have superseded this  this , but this is still pertinent to a Tableau developer


Consider this ER diagram:

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Note

We also appreciate that you may be unfamiliar with charts 3, 4 & 5, if you are unable to build charts 3, 4 & 5, please build replacement's replacements that you feel will compliment the rest of the charts in the collection.


It will be awsome awesome if you could add some interactivity into this too.

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