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Welcome!.

Published byAili Sala Modified over 5 years ago

Presentation on theme: "Welcome!."— Presentation transcript:

1 Welcome!

2 Forrest McDaniel www.forrestmcdaniel.com tsqladdict@gmail.com

3 NERD

7 California Vehicle Code 665.5
A “U-turn” is the turning of a vehicle upon a highway so as to proceed in the opposite direction whether accomplished by one continuous movement or not.

10 Roadmap Basic ideas Operators Tips for reading

11 BasicS

12 BasicS How would you store data?

13 Seek and scan Organized data is easier to search

14 B-Tree

17 B-Tree Navigation Pages Data Pages

18 B-Tree Root Page Leaf Pages

19 B-Tree 1≤N<4 4≤N Left Right

20 SEEK SCAN

21 Seek and scan

22 Clustered and Nonclustered Indexes

23 Clustered and Nonclustered Indexes

24 Execution Plans

25 Execution Plans suck

26 Execution Plans suck

27 Execution Plans suck

28 Top

29 Top

30 Filter

31 Filter

32 Filter

33 Sort

34 Sort

35 dbo.UsersDemo

36 ID Clustered Index DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int int int

37 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

38 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

39 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

40 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

41 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

42 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

43 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

44 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

45 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

46 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

47 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

48 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

50 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

51 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

52 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

53 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

54 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

55 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

56 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

57 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

58 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

59 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

60 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

61 ID PK DisplayName Nonclustered Index CreationDate Nonclustered Index Reputation Nonclustered Index int int int nvarchar(40) nvarchar(MAX) nvarchar(100) datetime int

64 Joins

65 Nested Loops

68 Nested Loops

69 Nested Loops

70 Nested Loops Best with small inputs.
Slooooow with really large inner inputs.

71 Merge

74 Merge Needs sorted data Many-to-many slows down

75 hash

78 hash “Semi-blocking” Needs memory

79 So which join is best?

80 Summary Join Strengths Weaknesses Commonly Seen Nested Loops
Simple, fast with good indexing Large inputs, bad cardinality estimates Small joins and proper indexing Merge Very fast with sorted inputs Sorting, many-to-many. Key to key joins, ORDER BY. Hash Generally fast Memory usage, spilling. Large joins. Heaps. No indexes.