More Than a Query Language: SQL in the 21 st Century @MarkusWinand - - PowerPoint PPT Presentation

more than a query language sql in the 21 st century
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More Than a Query Language: SQL in the 21 st Century @MarkusWinand - - PowerPoint PPT Presentation

More Than a Query Language: SQL in the 21 st Century @MarkusWinand @ModernSQL http://www.almaden.ibm.com/cs/people/chamberlin/sequel-1974.pdf 1974 1992 SQL-92 Tied to the Relational Idea SQL-92 Tied to the Relational Idea


slide-1
SLIDE 1

More Than a Query Language: SQL in the 21st Century

@MarkusWinand • @ModernSQL

http://www.almaden.ibm.com/cs/people/chamberlin/sequel-1974.pdf

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SLIDE 2
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SLIDE 3

1974 1992

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SLIDE 4

SQL-92 — Tied to the Relational Idea

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SLIDE 5

SQL-92 — Tied to the Relational Idea

Relational Data Model

  • “Atomic” types (domain)
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SLIDE 6

SQL-92 — Tied to the Relational Idea

Relational Data Model

  • “Atomic” types (domain)

Atom image: https://commons.wikimedia.org/wiki/File:Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.png

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SLIDE 7

SQL-92 — Tied to the Relational Idea

Relational Data Model

  • “Atomic” types (domain)

A B C

Atom image: https://commons.wikimedia.org/wiki/File:Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.png

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SLIDE 8

SQL-92 — Tied to the Relational Idea

Relational Data Model

  • “Atomic” types (domain)

A B C

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SLIDE 9

SQL-92 — Tied to the Relational Idea

Relational Data Model

  • “Atomic” types (domain)
  • Schema independent of


processing purposes

  • “Normalization”

A B C

slide-10
SLIDE 10

SQL-92 — Tied to the Relational Idea

Relational Data Model

  • “Atomic” types (domain)
  • Schema independent of


processing purposes

  • “Normalization”

A B C C D B E

slide-11
SLIDE 11

SQL-92 — Tied to the Relational Idea

Relational Data Model

  • “Atomic” types (domain)
  • Schema independent of


processing purposes

  • “Normalization”

Relational Operations

  • Transform data for


each particular
 processing purposes

  • JOIN, UNION, nesting, …

A B C C D B E A B C D E

slide-12
SLIDE 12

SQL-92 — Tied to the Relational Idea

Relational Data Model

  • “Atomic” types (domain)
  • Schema independent of


processing purposes

  • “Normalization”

Relational Operations

  • Transform data for


each particular
 processing purposes

  • JOIN, UNION, nesting, …

A B C C D B E

A B C D E

A B E

slide-13
SLIDE 13

SQL-92 — Tied to the Relational Idea

Relational Data Model

  • “Atomic” types (domain)
  • Schema independent of


processing purposes

  • “Normalization”

Relational Operations

  • Transform data for


each particular
 processing purposes

  • JOIN, UNION, nesting, …

A B C C D B E

A B C D E A B E

C D E

slide-14
SLIDE 14

SQL-92 — Tied to the Relational Idea

Relational Data Model

  • “Atomic” types (domain)
  • Schema independent of


processing purposes

  • “Normalization”

Relational Operations

  • Transform data for


each particular
 processing purposes

  • JOIN, UNION, nesting, …

A B C C D B E

A B C D E A B E C D E

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SLIDE 15

1992 1999

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SLIDE 16

https://www.wiscorp.com/DBMS_-_GreatNews-TheRelationalModelIsDead_-_paper_-_sam.pdf

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SLIDE 17

SQL:1999 — Escaping the Relational Cage

To say that these SQL:1999 extensions are mere 
 “extended interpretations” of the relational data model
 is like saying that an intercontinental ballistic missile is
 merely an “extended interpretation” of a spear.

https://www.wiscorp.com/DBMS_-_GreatNews-TheRelationalModelIsDead_-_paper_-_sam.pdf

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SLIDE 18

SQL:1999 — Escaping the Relational Cage

To say that these SQL:1999 extensions are mere 
 “extended interpretations” of the relational data model
 is like saying that an intercontinental ballistic missile is
 merely an “extended interpretation” of a spear. With SQL/99 you can get the best of both worlds and


  • f course, you can get the worst of both worlds.


It’s up to the database practitioners to do the right thing.

https://www.wiscorp.com/DBMS_-_GreatNews-TheRelationalModelIsDead_-_paper_-_sam.pdf

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SLIDE 19

SQL:1999 — Escaping the Relational Cage

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SLIDE 20

Relational Model?

SQL:1999 — Escaping the Relational Cage

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SLIDE 21

Relational Model?

Chris Date

Date on Database: Writings 2000-2006

SQL:1999 — Escaping the Relational Cage

I was as confused as anyone else

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SLIDE 22

Relational Model?

Chris Date

Date on Database: Writings 2000-2006

SQL:1999 — Escaping the Relational Cage

?

I was as confused as anyone else

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SLIDE 23

Relational Model?

Chris Date

Date on Database: Writings 2000-2006

SQL:1999 — Escaping the Relational Cage

? I was as confused as anyone else By the early 1990s, however,
 I’d seen the light

slide-24
SLIDE 24

Relational Model?

Chris Date

Date on Database: Writings 2000-2006

SQL:1999 — Escaping the Relational Cage

? I was as confused as anyone else By the early 1990s, however,
 I’d seen the light

Domains Can Contain Anything!

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SLIDE 25

Relational Model?

  • Introduced rich types

Chris Date

Date on Database: Writings 2000-2006

SQL:1999 — Escaping the Relational Cage

? I was as confused as anyone else By the early 1990s, however,
 I’d seen the light

Domains Can Contain Anything!

slide-26
SLIDE 26

Relational Model?

  • Introduced rich types

Chris Date

Date on Database: Writings 2000-2006

SQL:1999 — Escaping the Relational Cage

A

? I was as confused as anyone else By the early 1990s, however,
 I’d seen the light

Domains Can Contain Anything!

slide-27
SLIDE 27

Relational Model?

  • Introduced rich types
  • arrays

Chris Date

Date on Database: Writings 2000-2006

SQL:1999 — Escaping the Relational Cage

A B

[ , ] [ ] []

? I was as confused as anyone else By the early 1990s, however,
 I’d seen the light

Domains Can Contain Anything!

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SLIDE 28

Relational Model?

  • Introduced rich types
  • arrays
  • Nested tables (multiset)

Chris Date

Date on Database: Writings 2000-2006

SQL:1999 — Escaping the Relational Cage

A B

[ , ] [ ] []

C

C D C D C D

? I was as confused as anyone else By the early 1990s, however,
 I’d seen the light

Domains Can Contain Anything!

slide-29
SLIDE 29

Relational Model?

  • Introduced rich types
  • arrays
  • Nested tables (multiset)
  • composite types (objects)

Chris Date

Date on Database: Writings 2000-2006

SQL:1999 — Escaping the Relational Cage

A B C D

[ , ]

{x: , y: }

[ ]

{x: , y: }

[]

{x: , y: }

C D C D C D

? I was as confused as anyone else By the early 1990s, however,
 I’d seen the light

Domains Can Contain Anything!

slide-30
SLIDE 30

Relational Model?

  • Introduced rich types
  • arrays
  • Nested tables (multiset)
  • composite types (objects)

Non-Relational Operations

  • Introduced recursive


queries that process
 their own output

  • Transitive closure

Chris Date

Date on Database: Writings 2000-2006

SQL:1999 — Escaping the Relational Cage

? I was as confused as anyone else By the early 1990s, however,
 I’d seen the light

Domains Can Contain Anything!

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SLIDE 31

SQL:1999 — Recursion

CREATE TABLE t ( id INTEGER, parent INTEGER, )

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SLIDE 32

SQL:1999 — Recursion

CREATE TABLE t ( id INTEGER, parent INTEGER, )

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SLIDE 33

SQL:1999 — Recursion

CREATE TABLE t ( id INTEGER, parent INTEGER, )

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SLIDE 34

SQL:1999 — Recursion

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SLIDE 35

SQL:1999 — Recursion

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SLIDE 36

SQL:1999 — Recursion

SELECT t.id, t.parent FROM t WHERE t.id = ?

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SLIDE 37

SQL:1999 — Recursion

SELECT t.id, t.parent FROM t WHERE t.id = ? UNION ALL SELECT t.id, t.parent FROM t WHERE t.parent = ?

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SLIDE 38

SQL:1999 — Recursion

SELECT t.id, t.parent FROM t WHERE t.id = ? UNION ALL SELECT t.id, t.parent FROM t WHERE t.parent = ?

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SLIDE 39

SQL:1999 — Recursion

SELECT t.id, t.parent FROM t WHERE t.id = ? UNION ALL SELECT t.id, t.parent FROM t WHERE t.parent = ?

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SLIDE 40

SQL:1999 — Recursion

WITH RECURSIVE prev (id, parent) AS ( )
 SELECT t.id, t.parent FROM t WHERE t.id = ? UNION ALL SELECT t.id, t.parent FROM t JOIN prev ON t.parent = prev.id SELECT * FROM prev

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SLIDE 41

SQL:1999 — Recursion

WITH RECURSIVE prev (id, parent) AS ( )
 SELECT t.id, t.parent FROM t WHERE t.id = ? UNION ALL SELECT t.id, t.parent FROM t JOIN prev ON t.parent = prev.id SELECT * FROM prev

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SLIDE 42

SQL:1999 — Recursion

WITH RECURSIVE prev (id, parent) AS ( )
 SELECT t.id, t.parent FROM t WHERE t.id = ? UNION ALL SELECT t.id, t.parent FROM t JOIN prev ON t.parent = prev.id SELECT * FROM prev

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SLIDE 43

SQL:1999 — Recursion

1999 2001 2003 2005 2007 2009 2011 2013 2015 2017

5.1 10.2

MariaDB

8.0 MySQL 8.4

PostgreSQL

1.0 3.8.3

SQLite

7.0

DB2 LUW

11gR2

Oracle

2005

SQL Server

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SLIDE 44

1999 2003

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SLIDE 45

http://www.acm.org:80/sigmod/record/issues/0206/standard.pdf (via Wayback machine)

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SLIDE 46

SQL:2003 — Schemaless & Analytical

Schemaless

  • Introduced XML
  • Non-uniform


documents in
 a single column

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SLIDE 47

SQL:2003 — Schemaless & Analytical

Schemaless

  • Introduced XML
  • Non-uniform


documents in
 a single column

Later:

  • JSON added with SQL:2016
  • Proprietary JSON support:
  • 2012: PostgreSQL
  • 2014: Oracle
  • 2015: MySQL
  • 2016: SQL Server
slide-48
SLIDE 48

SQL:2003 — Schemaless & Analytical

Analytical

  • Introduced


window functions

  • Accessing other rows

  • f the current result

Schemaless

  • Introduced XML
  • Non-uniform


documents in
 a single column

Later:

  • JSON added with SQL:2016
  • Proprietary JSON support:
  • 2012: PostgreSQL
  • 2014: Oracle
  • 2015: MySQL
  • 2016: SQL Server
slide-49
SLIDE 49

SQL:2003 — Schemaless & Analytical

Analytical

  • Introduced


window functions

  • Accessing other rows

  • f the current result

Schemaless

  • Introduced XML
  • Non-uniform


documents in
 a single column

Later:

  • Extended in SQL:2011
  • Popular among “New SQLs”
  • 2013: BigQuery, Hive
  • 2014: Impala
  • 2015: Spark SQL
  • 2016: NuoDB, MemSQL,

Cockroach DB, VoltDB

Later:

  • JSON added with SQL:2016
  • Proprietary JSON support:
  • 2012: PostgreSQL
  • 2014: Oracle
  • 2015: MySQL
  • 2016: SQL Server
slide-50
SLIDE 50

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

SQL:2003 — Analytical

slide-51
SLIDE 51

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

slide-52
SLIDE 52

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

+10

slide-53
SLIDE 53

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

+10 +30 +20 +70 +40 +20

slide-54
SLIDE 54

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

, SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-55
SLIDE 55

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

ORDER BY id , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-56
SLIDE 56

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

ORDER BY id , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-57
SLIDE 57

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

ORDER BY id ROWS BETWEEN UNBOUNDED PRECEDING , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-58
SLIDE 58

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

ORDER BY id ROWS BETWEEN UNBOUNDED PRECEDING , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-59
SLIDE 59

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

ORDER BY id ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-60
SLIDE 60

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

ORDER BY id ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-61
SLIDE 61

SELECT id, value FROM t

id 1 2 3 4 5 6 value +10 +20

  • 10

+50

  • 30
  • 20

bal

SQL:2003 — Analytical

ORDER BY id ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-62
SLIDE 62

SELECT id, value FROM t

id value bal 1 +10 2 +20 3

  • 10

4 +50 5

  • 30

6

  • 20

SQL:2003 — Analytical

ORDER BY id ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-63
SLIDE 63

SELECT id, value FROM t

id value bal 1 +10 2 +20 3

  • 10

4 +50 5

  • 30

6

  • 20

SQL:2003 — Analytical

ORDER BY id ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-64
SLIDE 64

SELECT id, value FROM t

id value bal 1 +10 2 +20 3

  • 10

4 +50 5

  • 30

6

  • 20

SQL:2003 — Analytical

ORDER BY id ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-65
SLIDE 65

SELECT id, value FROM t

id value bal 1 +10 2 +20 3

  • 10

4 +50 5

  • 30

6

  • 20

SQL:2003 — Analytical

ORDER BY id ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-66
SLIDE 66

SELECT id, value FROM t

id value bal 1 +10 2 +20 3

  • 10

4 +50 5

  • 30

6

  • 20

SQL:2003 — Analytical

ORDER BY id ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW , SUM(value) OVER ( ) bal

+10 +30 +20 +70 +40 +20

slide-67
SLIDE 67

SQL:2003 — Analytical

1999 2001 2003 2005 2007 2009 2011 2013 2015 2017

5.1 10.2

MariaDB

8.0 MySQL 8.4

PostgreSQL

1.0 3.25.0

SQLite

7.0

DB2 LUW

8i

Oracle

2005[0] 2012

SQL Server

[0]Without framing

slide-68
SLIDE 68

SQL:2003 — Analytical

1999 2001 2003 2005 2007 2009 2011 2013 2015 2017

5.1 10.2

MariaDB

8.0 MySQL 8.4

PostgreSQL

1.0 3.25.0

SQLite

7.0

DB2 LUW

8i

Oracle

2005[0] 2012

SQL Server

[0]Without framing

Impala Spark NuoDB BigQuery Hive

slide-69
SLIDE 69

Inverse Distribution Functions (percentiles)

slide-70
SLIDE 70

SQL:2003 — Analytical (Median)

slide-71
SLIDE 71

SELECT d1.val FROM data d1 JOIN data d2 ON (d1.val < d2.val OR (d1.val=d2.val AND d1.id<d2.id)) GROUP BY d1.val HAVING count(*) = (SELECT FLOOR(COUNT(*)/2) FROM data d3)

SQL:2003 — Analytical (Median)

slide-72
SLIDE 72

SELECT d1.val FROM data d1 JOIN data d2 ON (d1.val < d2.val OR (d1.val=d2.val AND d1.id<d2.id)) GROUP BY d1.val HAVING count(*) = (SELECT FLOOR(COUNT(*)/2) FROM data d3)

Number rows

SQL:2003 — Analytical (Median)

slide-73
SLIDE 73

SELECT d1.val FROM data d1 JOIN data d2 ON (d1.val < d2.val OR (d1.val=d2.val AND d1.id<d2.id)) GROUP BY d1.val HAVING count(*) = (SELECT FLOOR(COUNT(*)/2) FROM data d3)

Number rows Pick middle one

SQL:2003 — Analytical (Median)

slide-74
SLIDE 74

SELECT d1.val FROM data d1 JOIN data d2 ON (d1.val < d2.val OR (d1.val=d2.val AND d1.id<d2.id)) GROUP BY d1.val HAVING count(*) = (SELECT FLOOR(COUNT(*)/2) FROM data d3)

Number rows Pick middle one

SQL:2003 — Analytical (Median)

slide-75
SLIDE 75

SELECT d1.val FROM data d1 JOIN data d2 ON (d1.val < d2.val OR (d1.val=d2.val AND d1.id<d2.id)) GROUP BY d1.val HAVING count(*) = (SELECT FLOOR(COUNT(*)/2) FROM data d3)

Number rows Pick middle one

SQL:2003 — Analytical (Median)

slide-76
SLIDE 76

SELECT d1.val FROM data d1 JOIN data d2 ON (d1.val < d2.val OR (d1.val=d2.val AND d1.id<d2.id)) GROUP BY d1.val HAVING count(*) = (SELECT FLOOR(COUNT(*)/2) FROM data d3)

Number rows Pick middle one

SQL:2003 — Analytical (Median)

Notice

All employees must

wash hands

after using

self-joins

slide-77
SLIDE 77

SELECT d1.val FROM data d1 JOIN data d2 ON (d1.val < d2.val OR (d1.val=d2.val AND d1.id<d2.id)) GROUP BY d1.val HAVING count(*) = (SELECT FLOOR(COUNT(*)/2) FROM data d3)

Number rows Pick middle one

SQL:2003 — Analytical (Median)

Notice

All employees must

wash hands

after using

self-joins

Grab stickers
 and coasters!

slide-78
SLIDE 78

SQL:2003 — Analytical (Median)

slide-79
SLIDE 79

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

SQL:2003 — Analytical (Median)

slide-80
SLIDE 80

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

Median

SQL:2003 — Analytical (Median)

slide-81
SLIDE 81

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

Median Which value?

SQL:2003 — Analytical (Median)

slide-82
SLIDE 82

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

SQL:2003 — Analytical (Median)

slide-83
SLIDE 83

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

Two variants:

  • for discrete values


(categories)

  • for continuous values


(linear interpolation)

SQL:2003 — Analytical (Median)

slide-84
SLIDE 84

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

Two variants:

  • for discrete values


(categories)

  • for continuous values


(linear interpolation)

SQL:2003 — Analytical (Median)

slide-85
SLIDE 85

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

Two variants:

  • for discrete values


(categories)

  • for continuous values


(linear interpolation)

SQL:2003 — Analytical (Median)

slide-86
SLIDE 86

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

Two variants:

  • for discrete values


(categories)

  • for continuous values


(linear interpolation)

SQL:2003 — Analytical (Median)

slide-87
SLIDE 87

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC(0.5)

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

Two variants:

  • for discrete values


(categories)

  • for continuous values


(linear interpolation)

SQL:2003 — Analytical (Median)

slide-88
SLIDE 88

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC(0.5)

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_CONT PERCENTILE_DISC(0.5)

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

Two variants:

  • for discrete values


(categories)

  • for continuous values


(linear interpolation)

SQL:2003 — Analytical (Median)

slide-89
SLIDE 89

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_DISC(0.5)

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_CONT PERCENTILE_DISC(0.5)

0.25 0.5 0.75 1

1 2 3 4 PERCENTILE_CONT(0.5) PERCENTILE_DISC(0.5)

SELECT PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY val) FROM data

Two variants:

  • for discrete values


(categories)

  • for continuous values


(linear interpolation)

SQL:2003 — Analytical (Median)

slide-90
SLIDE 90

SQL:2003 — PERCENTILE_DISC

1999 2001 2003 2005 2007 2009 2011 2013 2015 2017

5.1 10.3.7

[0]

MariaDB MySQL

9.4

PostgreSQL

1.0

SQLite DB2 LUW

9iR1

Oracle

2012[0]

SQL Server

[0]Only as window function (OVER required).

slide-91
SLIDE 91

SQL:2003 — PERCENTILE_DISC

1999 2001 2003 2005 2007 2009 2011 2013 2015 2017

5.1 10.3.7

[0]

MariaDB MySQL

9.4

PostgreSQL

1.0

SQLite DB2 LUW

9iR1

Oracle

2012[0]

SQL Server

[0]Only as window function (OVER required).

BigQuery Hive-16255 RESOLVED Fix Version: 4.0.0

slide-92
SLIDE 92

2003 2016

slide-93
SLIDE 93

SQL:2016 — JSON

http://standards.iso.org/ittf/PubliclyAvailableStandards/c067367_ISO_IEC_TR_19075-6_2017.zip

slide-94
SLIDE 94

SQL:2016 — JSON

[ { "id": 42, "a1": "foo" }, { "id": 43, "a1": "bar" } ]

http://standards.iso.org/ittf/PubliclyAvailableStandards/c067367_ISO_IEC_TR_19075-6_2017.zip

slide-95
SLIDE 95

SQL:2016 — JSON

id a1 42 foo 43 bar [ { "id": 42, "a1": "foo" }, { "id": 43, "a1": "bar" } ]

http://standards.iso.org/ittf/PubliclyAvailableStandards/c067367_ISO_IEC_TR_19075-6_2017.zip

slide-96
SLIDE 96

SELECT * FROM JSON_TABLE ( ? , '$[*]' COLUMNS ( id INT PATH '$.id' , a1 VARCHAR(…) PATH '$.a1' ) ) r

SQL:2016 — JSON_TABLE

[ { "id": 42, "a1": "foo" }, { "id": 43, "a1": "bar" } ]

id a1 42 foo 43 bar

slide-97
SLIDE 97

SELECT * FROM JSON_TABLE ( ? , '$[*]' COLUMNS ( id INT PATH '$.id' , a1 VARCHAR(…) PATH '$.a1' ) ) r

SQL:2016 — JSON_TABLE

[ { "id": 42, "a1": "foo" }, { "id": 43, "a1": "bar" } ]

id a1 42 foo 43 bar

Bind Parameter

slide-98
SLIDE 98

SELECT * FROM JSON_TABLE ( ? , '$[*]' COLUMNS ( id INT PATH '$.id' , a1 VARCHAR(…) PATH '$.a1' ) ) r

SQL:2016 — JSON_TABLE

[ { "id": 42, "a1": "foo" }, { "id": 43, "a1": "bar" } ]

id a1 42 foo 43 bar

SQL/JSON Path

  • Query language to

select elements from a JSON document

  • Defined in the


SQL standard

Bind Parameter

slide-99
SLIDE 99

SELECT * FROM JSON_TABLE ( ? , '$[*]' COLUMNS ( id INT PATH '$.id' , a1 VARCHAR(…) PATH '$.a1' ) ) r

SQL:2016 — JSON_TABLE

[ { "id": 42, "a1": "foo" }, { "id": 43, "a1": "bar" } ]

id a1 42 foo 43 bar

SQL/JSON Path

  • Query language to

select elements from a JSON document

  • Defined in the


SQL standard

Bind Parameter

slide-100
SLIDE 100

SELECT * FROM JSON_TABLE ( ? , '$[*]' COLUMNS ( id INT PATH '$.id' , a1 VARCHAR(…) PATH '$.a1' ) ) r

SQL:2016 — JSON_TABLE

[ { "id": 42, "a1": "foo" }, { "id": 43, "a1": "bar" } ]

id a1 42 foo 43 bar

SQL/JSON Path

  • Query language to

select elements from a JSON document

  • Defined in the


SQL standard

Bind Parameter

slide-101
SLIDE 101

SQL:2016 — JSON_TABLE — Use Case

SELECT * FROM JSON_TABLE ( ? , '$[*]' COLUMNS ( id INT PATH '$.id' , a1 VARCHAR(…) PATH '$.a1' ) ) r

[ { "id": 42, "a1": "foo" }, { "id": 43, "a1": "bar" } ]

id a1 42 foo 43 bar

slide-102
SLIDE 102

SQL:2016 — JSON_TABLE — Use Case

SELECT * FROM JSON_TABLE ( ? , '$[*]' COLUMNS ( id INT PATH '$.id' , a1 VARCHAR(…) PATH '$.a1' ) ) r INSERT INTO target_table

[ { "id": 42, "a1": "foo" }, { "id": 43, "a1": "bar" } ]

id a1 42 foo 43 bar

slide-103
SLIDE 103

SQL:2016 — JSON_TABLE

1999 2001 2003 2005 2007 2009 2011 2013 2015 2017

5.1

MariaDB

8.0 MySQL

PostgreSQL

1.0

SQLite

11.1.4.4

[0]

DB2 LUW

12cR1

Oracle

2016[1]

SQL Server

[0]Ridicoulus limitations: only 'strict $' as row expression [1]OPENJSON provides similar functionality

slide-104
SLIDE 104

SQL:2016 — JSON_TABLE

1999 2001 2003 2005 2007 2009 2011 2013 2015 2017

5.1

MariaDB

8.0 MySQL

PostgreSQL

1.0

SQLite

11.1.4.4

[0]

DB2 LUW

12cR1

Oracle

2016[1]

SQL Server

[0]Ridicoulus limitations: only 'strict $' as row expression [1]OPENJSON provides similar functionality

MDEV-17399 Tagged with
 fix/Version: 10.5 Patch available

slide-105
SLIDE 105

2011 2016

slide-106
SLIDE 106

SQL:2011 — Time Travelling

http://cs.ulb.ac.be/public/_media/teaching/infoh415/tempfeaturessql2011.pdf

slide-107
SLIDE 107

SQL:2011 — Time Travelling

Application Versioning

  • Dedicated syntax added
  • When did something


happen in the
 real world?

http://cs.ulb.ac.be/public/_media/teaching/infoh415/tempfeaturessql2011.pdf

slide-108
SLIDE 108

SQL:2011 — Time Travelling

Application Versioning

  • Dedicated syntax added
  • When did something


happen in the
 real world?

New syntax (excerpt)

  • FOR PORTION OF in


UPDATE and DELETE

  • WITHOUT OVERLAPS in UNIQUE

constraints & PRIMARY KEYS

  • [IMMEDIATELY] PRECEDES,

OVERLAPS in WHERE,HAVING,…

slide-109
SLIDE 109

SQL:2011 — Time Travelling

System Versioning

  • Fully automatic and


(almost) transparent

  • When did we learn


about something Application Versioning

  • Dedicated syntax added
  • When did something


happen in the
 real world?

New syntax (excerpt)

  • FOR PORTION OF in


UPDATE and DELETE

  • WITHOUT OVERLAPS in UNIQUE

constraints & PRIMARY KEYS

  • [IMMEDIATELY] PRECEDES,

OVERLAPS in WHERE,HAVING,…

slide-110
SLIDE 110

SQL:2011 — Time Travelling

System Versioning

  • Fully automatic and


(almost) transparent

  • When did we learn


about something Application Versioning

  • Dedicated syntax added
  • When did something


happen in the
 real world?

New syntax (excerpt)

  • FOR PORTION OF in


UPDATE and DELETE

  • WITHOUT OVERLAPS in UNIQUE

constraints & PRIMARY KEYS

  • [IMMEDIATELY] PRECEDES,

OVERLAPS in WHERE,HAVING,… Transparent changes, new syntax for queries

  • INSERT, UPDATE & DELETE


use the system time automatically

  • SELECT can use FOR

SYSTEM_TIME AS OF

slide-111
SLIDE 111

SQL:2011 — System Versioning

CREATE TABLE t ( ... , from TIMESTAMP(9) GENERATED ALWAYS
 AS ROW START , till TIMESTAMP(9) GENERATED ALWAYS
 AS ROW END
 , PERIOD FOR SYSTEM_TIME (from, till) ) WITH SYSTEM VERSIONING

slide-112
SLIDE 112

SQL:2011 — System Versioning

slide-113
SLIDE 113

SQL:2011 — System Versioning

INSERT INTO t (id, data)
 VALUES (1 , 'X' )

id data from till 1 X 10:00

slide-114
SLIDE 114

SQL:2011 — System Versioning

INSERT INTO t (id, data)
 VALUES (1 , 'X' )

id data from till 1 X 10:00

UPDATE t SET data = 'Y' WHERE id = 1

id data from till 1 X 10:00 11:00 1 Y 11:00

slide-115
SLIDE 115

SQL:2011 — System Versioning

INSERT INTO t (id, data)
 VALUES (1 , 'X' )

id data from till 1 X 10:00

UPDATE t SET data = 'Y' WHERE id = 1

id data from till 1 X 10:00 11:00 1 Y 11:00

DELETE FROM t WHERE id = 1

id data from till 1 X 10:00 11:00 1 Y 11:00 12:00

slide-116
SLIDE 116

SQL:2011 — System Versioning

id data from till 1 X 10:00 11:00 1 Y 11:00 12:00

slide-117
SLIDE 117

SQL:2011 — System Versioning

id data from till 1 X 10:00 11:00 1 Y 11:00 12:00

SELECT * FROM t

id data from till

slide-118
SLIDE 118

SQL:2011 — System Versioning

id data from till 1 X 10:00 11:00 1 Y 11:00 12:00

SELECT * FROM t

id data from till

SELECT * FROM t FOR SYSTEM_TIME AS OF
 TIMESTAMP'…10:30:00'

id data from till 1 X 10:00 11:00

slide-119
SLIDE 119

SQL:2011 — System Versioning

1999 2001 2003 2005 2007 2009 2011 2013 2015 2017

5.1 10.3

MariaDB MySQL PostgreSQL

1.0

SQLite

10.1

DB2 LUW

10gR1[0] 11gR1[1]

Oracle

2016

SQL Server

[0]Short term using Flashback. [1]Flashback Archive. Proprietery syntax.

slide-120
SLIDE 120

https://webstore.iec.ch/publication/59685

slide-121
SLIDE 121

A lot has
 happened since SQL-92

https://webstore.iec.ch/publication/59685

slide-122
SLIDE 122

SQL has evolved
 beyond the relational idea A lot has
 happened since SQL-92

https://webstore.iec.ch/publication/59685

slide-123
SLIDE 123

SQL has evolved
 beyond the relational idea If you use SQL for CRUD operations only, you are doing it wrong A lot has
 happened since SQL-92

slide-124
SLIDE 124

SQL has evolved
 beyond the relational idea If you use SQL for CRUD operations only, you are doing it wrong A lot has
 happened since SQL-92

https://modern-sql.com


@ModernSQL by @MarkusWinand

Training:
 https://winand.at/