1. I WANT TO HOLD
YOUR HAND
1ST TOP 100 SINGLE

2. A legacy of astonishing dominance
The Beatles in the Top 100
A legacy of astonishing dominance
585
313 68 19
Over more than 32 years, The Beatles had 585 entries in the Billboard Top 100.
In that time, at least one song by the Beatles was on the Top 100 chart in 313 different weeks.
John, Paul, George and Ringo produced 68 different songs which spent time in the Billboard Top 100.
From I Want to Hold Your Hand to The Long and Winding Road, 19 different Beatles singles spent at least a week on top of the charts.

3. WINDOWING FUNCTIONS
SHEDDING SOME LIGHT

4. James McGillivray / BI Architect
About Me
Hey Jude James
Professional
10 Years BI Experience
Microsoft Certified
SQL User Group Johannesburg, South Africa
Personal
Sport: Cricket, Soccer, Squash, Running Slowly.
Culture: Symphony Choir of Johannesburg, Musical Theatre
Other: Board Games, Poker
James McGillivray / BI Architect
@JamesMcG_MSBI
TheJimmyRSA

5. The Long and Winding Road
Where we’re going
What Goes On
SESSION OBJECTIVES
INTRODUCTION TO WINDOWING FUNCTIONS
Do You Want To
Know A Secret
THE OVER CLAUSE

6. The Long and Winding Road
Where we’re going
What Goes On
SESSION OBJECTIVES
INTRODUCTION TO WINDOWING FUNCTIONS
Do You Want To
Know A Secret
THE OVER CLAUSE

7. Eight Days a Week With a Little Help From My Friends Yesterday
RANKING FUNCTIONS AND ORDER BY
With a Little Help From
My Friends
PARTITION BY
Yesterday
LEAD AND LAG
ROWS AND RANGES
Come Together
GROUP BY

8. Eight Days a Week With a Little Help From My Friends Yesterday
RANKING FUNCTIONS AND ORDER BY
With a Little Help From
My Friends
PARTITION BY
Yesterday
LEAD AND LAG
ROWS AND RANGES
Come Together
GROUP BY

9. You Can’t Do That
RESTRICTIONS
Help
QUESTIONS

10. Visualise the Concepts Demonstrate the Functionality
Session Objectives
Learn the Syntax
We’ll go through each clause available in Windowing functions, building from simplest to most complex
Visualise the Concepts
Demonstrate the Functionality
After each clause is explained, see it demonstrated in an abstract but simple way.
See the incredible power of the functions as we explore the music of THE BEATLES.
WHAT GOES ON

11. Introduction to Windowing Functions
Introduced in SQL 2012
Although RANKING functions already existed
Ranking, Aggregation, Analytical
Windowing functions reduce query complexity for common patterns
Avoid Self-Joins
Many queries can get rid of self-joins by using windowing functions
WHAT GOES ON

12. Introduction to Windowing Functions10 50
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200 50 3 7 11 15 40 50
1000 50 4 8 12 16
Demo Table (RowID, Colour, Value)
WHAT GOES ON

13. The Over Clause Aggregations without Group By?
Aggregation is performed OVER all rows in the data set
Add Information Result Set
Use data from the entire data set on each row in the set
Totals
Calculate totals over the set.
Total # of Weeks Beatles songs spent on chart.
Other Uses
% of Total
Average of Entire Set
Do You Want To Know A Secret?

14. The Over Clause count(*) over () 16 Do You Want To Know A Secret? 1050
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1000 16 20
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1000 50
count(*) over ()
Do You Want To Know A Secret?

15. The Over Clause sum(Value) over () Do You Want To Know A Secret? 315010 50
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3150 20
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100 30
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1000 50
sum(Value) over ()
Do You Want To Know A Secret?

16. The Over Clause
DEMO
Do You Want To Know A Secret?

17. Ranking Functions and the Order By Clause
Position of Current Row in Set
Must have an order by to determine sorting
row_number()
Ignore ties. Specify multiple columns in order by
to avoid unexpected behaviour
rank()
Assign ties the same value. Skip values after ties
dense_rank()
Assign ties the same value. Do not skip value after ties.
EIGHT DAYS A WEEK

18. Ranking Functions and the Order By Clause10 50
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1000 1 5 10 16 20
100
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100 2 9 12 11 30
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200 50 3 13 14 7 40 50
1000 50 4 6 15 8
row_number() over (order by VALUE)
EIGHT DAYS A WEEK

19. Ranking Functions and the Order By Clause10 50
100
1000 1 7 10 16 20
100
150
100 2 9 12 11 30
200
200 50 3 13 14 8 40 50
1000 50 4 6 15 5
row_number() over (order by VALUE)
EIGHT DAYS A WEEK

20. Ranking Functions and the Order By Clause10 50
100
1000 1 1 8 12 20
100
150
100 1 6 8 14 30
200
200 50 1 6 8 14 40 50
1000 50 1 8 12 14
rank() over (order by COLOUR)
EIGHT DAYS A WEEK

21. Ranking Functions and the Order By Clause10 50
100
1000 1 1 3 4 20
100
150
100 1 2 3 5 30
200
200 50 1 2 3 5 40 50
1000 50 1 3 4 5
dense_rank() over (order by COLOUR)
EIGHT DAYS A WEEK

22. Ranking Functions and the Order By Clause
DEMO
EIGHT DAYS A WEEK

23. The Partition By Clause
Split the data into groups
Perform aggregation over the partitions
Sub-Totals
Totals per Category
Other Uses
Percentage of Sub-Total
Ranking within group
WITH A LITTLE HELP FROM MY FRIENDS

24. The Partition By Clause10 50
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2000 20
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200 50
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1000 50
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sum(VALUE) over (partition by COLOUR)
WITH A LITTLE HELP FROM MY FRIENDS

25. The Partition By Clause10 50
100
1000 1 5 2 2 20
100
150
100 2 1 3 3 30
200
200 50 3 2 4 2 40 50
1000 50 4 1 1 1
row_number() over (partition by COLOUR order by VALUE)
WITH A LITTLE HELP FROM MY FRIENDS

26. The Partition By Clause
DEMO
WITH A LITTLE HELP FROM MY FRIENDS

27. LEAD and LAG/ROWS and RANGES
Order data within groups
Must use the Order By clause with ROWS
Calculate relative to row order
All before this row. 1 after this row etc.
Analysis within subset of partition
Previous 3 Months Average Sales
Year-on-Year Variance
WITH A LITTLE HELP FROM MY FRIENDS

28. LEAD and LAG 10 50
100
1000
NULL 40 50
1000 20
100
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100 10
NULL
100
NULL 30
200
200 50 20
100
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100 40 50
1000 50 30
NULL
NULL 50
lag(VALUE,1,NULL) over (partition by COLOUR order by ROWID)
WITH A LITTLE HELP FROM MY FRIENDS

29. LEAD and LAG
DEMO
WITH A LITTLE HELP FROM MY FRIENDS

30. ROWS and RANGES sum(VALUE) over (partition by COLOUR order by POSITION10 50
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1000 10
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100 30
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200 50 60
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150 40 50
1000 50
100 50
1000
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sum(VALUE) over (partition by COLOUR order by POSITION
ROWS UNBOUNDED PRECEDING)
WITH A LITTLE HELP FROM MY FRIENDS

31. ROWS and RANGES 10 50
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1000 10 90
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100 30
100
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100 30
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200 50 50
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150 40 50
1000 50 70 50
1000
100
sum(VALUE) over (partition by COLOUR order by POSITION ROWS BETWEEN 1 PRECEDING AND CURRENT ROW)
WITH A LITTLE HELP FROM MY FRIENDS

32. ROWS and RANGES
DEMO
WITH A LITTLE HELP FROM MY FRIENDS

33. Group By Aggregations of Aggregations COME TOGETHER
Perform windowing functions on Aggregations
SUM(COUNT())
MAX(AVG())
COME TOGETHER

34. Group By
DEMO
COME TOGETHER

35. Restrictions
YOU CAN’T DO THaT

36. Restrictions Only in Select Statement YOU CAN’T DO THaT
No where row_order() = 1
YOU CAN’T DO THaT

37. Should I have called this slide
Questions
Questions
Should I have called this slide
FROM ME TO YOU?
@JamesMcG_MSBI
TheJimmyRSA
HELP