Datalog: Biting the Silver Bullet

Transcript

1. Datalog: Biting the Silver Bullet Norbert Wójtowicz · @pithyless
2. Information Systems Ȑ |
3. Ȑ | DATA Information Systems
4. D A T A Ȑ | 1 D,T 2 A DATA Information Systems
5. D A T A Ȑ | 1 D,T 2 A DATA Information Systems
6. Data Stream · Tree · Mesh
7. ⦾→⦾→⦾→⦾ Data
8. Data
9. Data
10. Data
11. Data
12. Data
13. Data
14. Data
15. Data
16. One-Way Data Flow Events → Log → Views
17. One-Way Data Flow Kafka → Batch → DBs
18. One-Way Data Flow Transactor → Storage → Peers
19. One-Way Data Flow Queue → Log → Indices
20. Datalog Entity · Attribute · Value
21. GitHub
22. Entity · Attribute · Value e a v [entity attribute value]
23. Entity · Attribute · Value [entity attribute value] {:user/name “richhickey”} {:user/name “tonsky”} {:user/name “pithyless”} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
24. Entity · Attribute · Value [entity attribute value] {:user/name “richhickey”} {:user/name “tonsky”} {:user/name “pithyless”} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
25. Entity · Attribute · Value [entity attribute value] {:user/name “richhickey”} {:user/name “tonsky”} {:user/name “pithyless”} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
26. Pattern Matching - Constants [11 _ _] [_ _ “pithyless”] [_ :user/name _] [22 :user/name “tonsky”] [11 :user/name “tonsky”] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
27. Pattern Matching - Constants [11 _ _] [_ _ “pithyless”] [_ :user/name _] [22 :user/name “tonsky”] [11 :user/name “tonsky”] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
28. Pattern Matching - Constants [11 _ _] [_ _ “pithyless”] [_ :user/name _] [22 :user/name “tonsky”] [11 :user/name “tonsky”] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
29. Pattern Matching - Constants [11 _ _] [_ _ “pithyless”] [_ :user/name _] [22 :user/name “tonsky”] [11 :user/name “tonsky”] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
30. Pattern Matching - Constants [11 _ _] [_ _ “pithyless”] [_ :user/name _] [22 :user/name “tonsky”] [11 :user/name “tonsky”] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
31. Pattern Matching - Bindings [?e _ _] [_ ?a _] [_ _ ?v] [?e ?a _] [?e _ ?v] [?e ?a ?v] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
32. Pattern Matching - Bindings [?e _ _] [_ ?a _] [_ _ ?v] [?e ?a _] [?e _ ?v] [?e ?a ?v] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
33. Pattern Matching - Bindings [?e _ _] [_ ?a _] [_ _ ?v] [?e ?a _] [?e _ ?v] [?e ?a ?v] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
34. Pattern Matching - Bindings [?e _ _] [_ ?a _] [_ _ ?v] [?e ?a _] [?e _ ?v] [?e ?a ?v] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
35. Pattern Matching - Bindings [?e _ _] [_ ?a _] [_ _ ?v] [?e ?a _] [?e _ ?v] [?e ?a ?v] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
36. Pattern Matching - Bindings [?e _ _] [_ ?a _] [_ _ ?v] [?e ?a _] [?e _ ?v] [?e ?a ?v] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
37. Pattern Matching - Mix & Match [?e :user/name “pithyless”] [11 :user/name ?v] [?e :user/name ?v] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
38. Pattern Matching - Mix & Match [?e :user/name “pithyless”] [11 :user/name ?v] [?e :user/name ?v] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
39. Pattern Matching - Mix & Match [?e :user/name “pithyless”] [11 :user/name ?v] [?e :user/name ?v] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
40. Basic Query [:find ?name :where [11 :user/name ?name]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
41. Basic Query [:find ?name :where [11 :user/name ?name]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
42. Basic Query e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless [:find ?name :where [11 :user/name ?name]] ∈{[“richhickey”]}
43. Basic Query [:find ?id :where [?id :user/name “tonsky”]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
44. Basic Query [:find ?id :where [?id :user/name “tonsky”]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
45. Basic Query [:find ?id :where [?id :user/name “tonsky”]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless ∈{[22]}
46. Sets [:find ?name :where [_ :user/name ?name]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
47. Sets [:find ?name :where [_ :user/name ?name]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
48. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless [:find ?name :where [_ :user/name ?name]] ∈{[“richhickey”] [“tonsky”] [“pithyless”]} Sets
49. Sets [:find ?attr :where [_ ?attr _]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
50. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless ∈{[:user/name]} Sets [:find ?attr :where [_ ?attr _]]
51. Sets · Lists · Scalars [:find ?name :where [_ :user/name ?name]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
52. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless [:find ?name :where [_ :user/name ?name]] ∈{[“richhickey”] [“tonsky”] [“pithyless”]} Sets · Lists · Scalars
53. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless [:find [?name ...] :where [_ :user/name ?name]] [“richhickey” “tonsky” “pithyless”] Sets · Lists · Scalars
54. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless [:find ?name . :where [_ :user/name ?name]] “tonsky” Sets · Lists · Scalars
55. Multiple Bindings [:find ?id ?name :where [?id :user/name ?name]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
56. Multiple Bindings [:find ?id ?name :where [?id :user/name ?name]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
57. Multiple Bindings [:find ?id ?name :where [?id :user/name ?name]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
58. ∈{[11 “richhickey”] [22 “tonsky”] [33 “pithyless”]} [:find ?id ?name :where [?id :user/name ?name]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless Multiple Bindings
59. Entity {:user/name “richhickey” :user/email “rich@e.com”} {:user/name “tonsky” :user/email “nikita@e.com"} {:user/name “pithyless” :user/email “norbert@e.com”} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com
60. Entity {:user/name “richhickey” :user/email “rich@e.com”} {:user/name “tonsky” :user/email “nikita@e.com"} {:user/name “pithyless” :user/email “norbert@e.com”} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com
61. Entity {:user/name “richhickey” :user/email “rich@e.com”} {:user/name “tonsky” :user/email “nikita@e.com"} {:user/name “pithyless” :user/email “norbert@e.com”} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com
62. Entity {:user/name “richhickey” :user/email “rich@e.com”} {:user/name “tonsky” :user/email “nikita@e.com"} {:user/name “pithyless” :user/email “norbert@e.com”} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com
63. Join e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com [:find ?email :where [?id :user/name “richhickey”] [?id :user/email ?email]]
64. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com [:find ?email :where [?id :user/name “richhickey”] [?id :user/email ?email]] Join
65. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com [:find ?email :where [?id :user/name “richhickey”] [?id :user/email ?email]] Join
66. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com [:find ?email :where [?id :user/name “richhickey”] [?id :user/email ?email]] Join
67. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com [:find ?email :where [?id :user/name “richhickey”] [?id :user/email ?email]] ∈{[“rich@e.com”]} Join
68. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com [:find ?name :where [?id :user/name ?name] [?id :user/email “rich@e.com”]] ∈{[“richhickey”]} Join
69. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com [:find ?name :where [?id :user/name ?name] [?id :user/email “fake”]] ∈{} Join
70. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 11 :user/email rich@e.com 22 :user/email nikita@e.com 33 :user/email norbert@e.com [:find ?name ?email :where [?id :user/name ?name] [?id :user/email ?email]] ∈{[“richhickey” “rich@e.com”] [“tonsky” “nikita@e.com”] [“pithyless” “norbert@e.com”]} Join
71. Reference {:org/name “clojure”} {:repo/slug "clojure/clojure" :repo/owner 44} {:repo/slug "tonsky/datascript" :repo/owner 22} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22
72. Reference {:org/name “clojure”} {:repo/slug "clojure/clojure" :repo/owner 44} {:repo/slug "tonsky/datascript" :repo/owner 22} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22
73. Reference {:org/name “clojure”} {:repo/slug "clojure/clojure" :repo/owner 44} {:repo/slug "tonsky/datascript" :repo/owner 22} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22
74. Reference {:org/name “clojure”} {:repo/slug "clojure/clojure" :repo/owner 44} {:repo/slug "tonsky/datascript" :repo/owner 22} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22
75. Reference - Ident e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 {:org/name “clojure”} {:repo/slug "clojure/clojure" :repo/owner [:org/name “clojure”]} {:repo/slug "tonsky/datascript" :repo/owner [:user/name “tonsky"]}
76. Follow References [:find ?repo :where [?p :user/name “tonsky”] [?r :repo/owner ?p] [?r :repo/slug ?repo]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22
77. [:find ?repo :where [?p :user/name “tonsky”] [?r :repo/owner ?p] [?r :repo/slug ?repo]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 Follow References
78. [:find ?repo :where [?p :user/name “tonsky”] [?r :repo/owner ?p] [?r :repo/slug ?repo]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 Follow References
79. [:find ?repo :where [?p :user/name “tonsky”] [?r :repo/owner ?p] [?r :repo/slug ?repo]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 Follow References
80. [:find ?repo :where [?p :user/name “tonsky”] [?r :repo/owner ?p] [?r :repo/slug ?repo]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 ∈{[“tonsky/datascript”]} Follow References
81. [:find ?name :where [?p :user/name ?name] [?r :repo/owner ?p] [?r :repo/slug “tonsky/datascript”]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 ∈{[“tonsky”]} Follow References - Reverse
82. Polymorphic References [:find ?name ?repo :where [?p :user/name ?name] [?r :repo/owner ?p] [?r :repo/slug ?repo]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 ∈{[“tonsky” “tonsky/datascript”]}
83. Polymorphic References [:find ?name ?repo :where [?p :org/name ?name] [?r :repo/owner ?p] [?r :repo/slug ?repo]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 ∈{[“clojure” “clojure/clojure”]}
84. Polymorphic References [:find ?name ?repo :where (or [?p :org/name ?name] [?p :user/name ?name]) [?r :repo/owner ?p] [?r :repo/slug ?repo]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 ∈{[“tonsky” “tonsky/datascript”] [“clojure” “clojure/clojure”]}
85. Rules [:find ?name ?repo :where [(repo-owner ?p ?name)] [?r :repo/owner ?p] [?r :repo/slug ?repo]] [[(repo-owner ?p ?name) [?p :org/name ?name]] [(repo-owner ?p ?name) [?p :user/name ?name]]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22
86. Circular References {:repo/slug “pithyless/datascript" :repo/owner [:user/name “pithyless"] :repo/fork [:repo/slug "tonsky/datascript"]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 77 :repo/slug pithyless/datascript 77 :repo/owner 33 77 :repo/fork 66
87. Circular References {:repo/slug “pithyless/datascript" :repo/owner [:user/name “pithyless"] :repo/fork [:repo/slug "tonsky/datascript"]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 77 :repo/slug pithyless/datascript 77 :repo/owner 33 77 :repo/fork 66
88. Find forks [:find ?repo :where [?r :repo/slug ?repo] [?r :repo/fork _]] ∈{[“pithyless/datascript”]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 77 :repo/slug pithyless/datascript 77 :repo/owner 33 77 :repo/fork 66
89. Find originals [:find ?repo :where [?r :repo/slug ?repo] [(missing ?r :repo/fork)]] ∈{[“clojure/clojure”] [“tonsky/datascript”]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 77 :repo/slug pithyless/datascript 77 :repo/owner 33 77 :repo/fork 66
90. List forks [:find ?orig ?fork :where [?orig-id :repo/slug ?orig] [?fork-id :repo/slug ?fork] [?fork-id :repo/fork ?orig-id]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 77 :repo/slug pithyless/datascript 77 :repo/owner 33 77 :repo/fork 66
91. List forks [:find ?orig ?fork :where [?orig-id :repo/slug ?orig] [?fork-id :repo/slug ?fork] [?fork-id :repo/fork ?orig-id]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 77 :repo/slug pithyless/datascript 77 :repo/owner 33 77 :repo/fork 66
92. List forks [:find ?orig ?fork :where [?orig-id :repo/slug ?orig] [?fork-id :repo/slug ?fork] [?fork-id :repo/fork ?orig-id]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 77 :repo/slug pithyless/datascript 77 :repo/owner 33 77 :repo/fork 66
93. List forks [:find ?orig ?fork :where [?orig-id :repo/slug ?orig] [?fork-id :repo/slug ?fork] [?fork-id :repo/fork ?orig-id]] ∈{[“tonsky/datascript” “pithyless/datascript”]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 44 :org/name clojure 55 :repo/slug clojure/clojure 55 :repo/owner 44 66 :repo/slug tonsky/datascript 66 :repo/owner 22 77 :repo/slug pithyless/datascript 77 :repo/owner 33 77 :repo/fork 66
94. Multiple Values {:repo/slug "clojure/clojure" :repo/lang [“clojure” “java”]} {:repo/slug "tonsky/datascript" :repo/lang [“clojure” “javascript”]} {:repo/slug "pithyless/datascript" :repo/lang [“clojure” “javascript”]} e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 55 :repo/lang clojure 55 :repo/lang javascript 55 :repo/lang clojure 55 :repo/lang javascript
95. Multiple Values {:repo/slug "clojure/clojure" :repo/lang [“clojure” “java”]} {:repo/slug "tonsky/datascript" :repo/lang [“clojure” “javascript”]} {:repo/slug "pithyless/datascript" :repo/lang [“clojure” “javascript”]} e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 55 :repo/lang clojure 55 :repo/lang javascript 55 :repo/lang clojure 55 :repo/lang javascript
96. Multiple Values {:repo/slug "clojure/clojure" :repo/lang [“clojure” “java”]} {:repo/slug "tonsky/datascript" :repo/lang [“clojure” “javascript”]} {:repo/slug "pithyless/datascript" :repo/lang [“clojure” “javascript”]} e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 55 :repo/lang clojure 55 :repo/lang javascript
97. Multiple Values {:repo/slug "clojure/clojure" :repo/lang [“clojure” “java”]} {:repo/slug "tonsky/datascript" :repo/lang [“clojure” “javascript”]} {:repo/slug "pithyless/datascript" :repo/lang [“clojure” “javascript”]} e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 77 :repo/lang clojure 77 :repo/lang javascript
98. Multiple Values e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 77 :repo/lang clojure 77 :repo/lang javascript [:find ?lang :where [_ :repo/lang ?lang]]
99. Multiple Values e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 77 :repo/lang clojure 77 :repo/lang javascript [:find ?lang :where [_ :repo/lang ?lang]]
100. Multiple Values e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 77 :repo/lang clojure 77 :repo/lang javascript [:find ?lang :where [_ :repo/lang ?lang]] ∈{[“clojure”] [“java”] [“javascript”]}
101. Multiple Values [:find ?repo ?lang :where [?r :repo/slug ?repo] [?r :repo/lang ?lang]] e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 77 :repo/lang clojure 77 :repo/lang javascript
102. Multiple Values [:find ?repo ?lang :where [?r :repo/slug ?repo] [?r :repo/lang ?lang]] e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 77 :repo/lang clojure 77 :repo/lang javascript
103. Multiple Values [:find ?repo ?lang :where [?r :repo/slug ?repo] [?r :repo/lang ?lang]] e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 77 :repo/lang clojure 77 :repo/lang javascript
104. Multiple Values [:find ?repo ?lang :where [?r :repo/slug ?repo] [?r :repo/lang ?lang]] e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 77 :repo/lang clojure 77 :repo/lang javascript
105. Multiple Values [:find ?repo ?lang :where [?r :repo/slug ?repo] [?r :repo/lang ?lang]] e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 77 :repo/lang clojure 77 :repo/lang javascript
106. Multiple Values e a v 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 55 :repo/lang clojure 55 :repo/lang java 66 :repo/lang clojure 66 :repo/lang javascript 77 :repo/lang clojure 77 :repo/lang javascript [:find ?repo ?lang :where [?r :repo/slug ?repo] [?r :repo/lang ?lang]] ∈{[“clojure/clojure” “clojure”] [“clojure/clojure” “java”] [“tonsky/datascript” “clojure”] [“tonsky/datascript” “javascript”] [“pithyless/datascript” “clojure”] [“pithyless/datascript” “javascript”]}
107. Multiple References {:user/name "richhickey" :user/stars [[:repo/slug “clojure/clojure"]]} {:user/name "tonsky" :user/stars [[:repo/slug "clojure/clojure"] [:repo/slug “tonsky/datascript"]]} {:user/name “pithyless" :user/stars [[:repo/slug "clojure/clojure"] [:repo/slug “tonsky/datascript"]]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 11 :user/stars 55 22 :user/stars 55 22 :user/stars 66 33 :user/stars 55 33 :user/stars 66
108. Multiple References {:user/name "richhickey" :user/stars [[:repo/slug “clojure/clojure"]]} {:user/name "tonsky" :user/stars [[:repo/slug "clojure/clojure"] [:repo/slug “tonsky/datascript"]]} {:user/name “pithyless" :user/stars [[:repo/slug "clojure/clojure"] [:repo/slug “tonsky/datascript"]]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 11 :user/stars 55 22 :user/stars 55 22 :user/stars 66 33 :user/stars 55 33 :user/stars 66
109. Multiple References {:user/name "richhickey" :user/stars [[:repo/slug “clojure/clojure"]]} {:user/name "tonsky" :user/stars [[:repo/slug "clojure/clojure"] [:repo/slug “tonsky/datascript"]]} {:user/name “pithyless" :user/stars [[:repo/slug "clojure/clojure"] [:repo/slug “tonsky/datascript"]]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 11 :user/stars 55 22 :user/stars 55 22 :user/stars 66 33 :user/stars 55 33 :user/stars 66
110. Multiple References {:user/name "richhickey" :user/stars [[:repo/slug “clojure/clojure"]]} {:user/name "tonsky" :user/stars [[:repo/slug "clojure/clojure"] [:repo/slug “tonsky/datascript"]]} {:user/name “pithyless" :user/stars [[:repo/slug "clojure/clojure"] [:repo/slug “tonsky/datascript"]]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 11 :user/stars 55 22 :user/stars 55 22 :user/stars 66 33 :user/stars 55 33 :user/stars 66
111. Aggregations [:find ?repo (count ?p) :where [?r :repo/slug ?repo] [?p :user/stars ?r]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 11 :user/stars 55 22 :user/stars 55 22 :user/stars 66 33 :user/stars 55 33 :user/stars 66
112. Aggregations [:find ?repo (count ?p) :where [?r :repo/slug ?repo] [?p :user/stars ?r]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 11 :user/stars 55 22 :user/stars 55 22 :user/stars 66 33 :user/stars 55 33 :user/stars 66
113. Aggregations [:find ?repo (count ?p) :where [?r :repo/slug ?repo] [?p :user/stars ?r]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 11 :user/stars 55 22 :user/stars 55 22 :user/stars 66 33 :user/stars 55 33 :user/stars 66
114. Aggregations [:find ?repo (count ?p) :where [?r :repo/slug ?repo] [?p :user/stars ?r]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 11 :user/stars 55 22 :user/stars 55 22 :user/stars 66 33 :user/stars 55 33 :user/stars 66
115. Aggregations [:find ?repo (count ?p) :where [?r :repo/slug ?repo] [?p :user/stars ?r]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 11 :user/stars 55 22 :user/stars 55 22 :user/stars 66 33 :user/stars 55 33 :user/stars 66
116. Aggregations e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript 11 :user/stars 55 22 :user/stars 55 22 :user/stars 66 33 :user/stars 55 33 :user/stars 66 ∈{[“clojure/clojure” 3] [“tonsky/datascript” 2]} [:find ?repo (count ?p) :where [?r :repo/slug ?repo] [?p :user/stars ?r]]
117. Predicates [:find ?repo :where [_ :repo/slug ?repo] [(.startsWith ?repo “c”)]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript
118. Predicates [:find ?repo :where [_ :repo/slug ?repo] [(.startsWith ?repo “c”)]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript
119. Predicates [:find ?repo :where [_ :repo/slug ?repo] [(.startsWith ?repo “c”)]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript
120. Predicates ∈{[“clojure/clojure”]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript [:find ?repo :where [_ :repo/slug ?repo] [(.startsWith ?repo “c”)]]
121. Fulltext Search [:find ?repo ?score :where [(fulltext :repo/slug “clojure”) [[?r ?repo _ ?score]]] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript
122. Fulltext Search [:find ?repo ?score :where [(fulltext :repo/slug “clojure”) [[?r ?repo _ ?score]]] ∈{[“clojure/clojure” 0.99]} e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript
123. Coffee?
124. Datalog Entity · Attribute · Value
125. e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript Databases as Indices
126. Key / Value [:find ?repo :where [_ :repo/slug ?repo]] a v e :repo/slug clojure/clojure 55 :repo/slug pithyless/datascript 77 :repo/slug tonsky/datascript 66 :user/name pithyless 33 :user/name richhickey 11 :user/name tonsky 22 :user/stars 55 11 :user/stars 55 22 :user/stars 55 33 :user/stars 66 22 :user/stars 66 33
127. Row [:find ?name :where [11 :user/name ?name]] e a v 11 :user/name richhickey 11 :user/stars 55 22 :user/name tonsky 22 :user/stars 55 22 :user/stars 66 33 :user/name pithyless 33 :user/stars 55 33 :user/stars 66 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript
128. Column [:find ?p (count ?p) :where [?p :user/stars _]] a e v :repo/slug 55 clojure/clojure :repo/slug 66 tonsky/datascript :repo/slug 77 pithyless/datascript :user/name 11 richhickey :user/name 22 tonsky :user/name 33 pithyless :user/stars 11 55 :user/stars 22 55 :user/stars 22 66 :user/stars 33 55 :user/stars 33 66
129. Document [:find ?repo :where [11 :user/stars ?r] [?r :repo/slug ?repo] e a v 11 :user/name richhickey 11 :user/stars 55 22 :user/name tonsky 22 :user/stars 55 22 :user/stars 66 33 :user/name pithyless 33 :user/stars 55 33 :user/stars 66 55 :repo/slug clojure/clojure 66 :repo/slug tonsky/datascript 77 :repo/slug pithyless/datascript
130. Graph [:find ?e :where [?e :user/stars ?r] [?r :repo/slug “clojure/clojure”] v a e 55 :user/stars 11 55 :user/stars 22 55 :user/stars 33 66 :user/stars 22 66 :user/stars 33 clojure/clojure :repo/slug 55 pithyless :user/name 33 pithyless/datascript :repo/slug 77 richhickey :user/name 11 tonsky :user/name 22 tonsky/datascript :repo/slug 66
131. Databases as Indices Structure Index key/value A · V · E row E · A · V column A · E · V document E · A · V graph V · A · E search inverted-index
132. Reified Attributes 11 :user/name richhickey 2 :db/ident :user/name 2 :db/valueType :db.type/string 2 :db/doc “GitHub username” 2 :db/unique :db.unique/identity 2 :db/fulltext true
133. Reified Attributes 11 2 richhickey 2 :db/ident :user/name 2 :db/valueType :db.type/string 2 :db/doc “GitHub username” 2 :db/unique :db.unique/identity 2 :db/fulltext true
134. Reified Attributes 11 2 richhickey 2 :db/ident :user/name 2 :db/valueType :db.type/string 2 :db/doc “GitHub username” 2 :db/unique :db.unique/identity 2 :db/fulltext true
135. Reified Attributes 11 2 richhickey 2 :db/ident :user/name 2 :db/valueType :db.type/string 2 :db/doc “GitHub username” 2 :db/unique :db.unique/identity 2 :db/fulltext true
136. Reified Attributes 11 2 richhickey 2 :db/ident :user/name 2 :db/valueType :db.type/string 2 :db/doc “GitHub username” 2 :db/unique :db.unique/identity 2 :db/fulltext true
137. Reified Attributes 11 2 richhickey 2 :db/ident :user/name 2 :db/valueType :db.type/string 2 :db/doc “GitHub username” 2 :db/unique :db.unique/identity 2 :db/fulltext true
138. Transactions [entity attribute value] e a v 11 :user/name richhickey 22 :user/name tonsky 33 :user/name pithyless
139. Transactions [entity attribute value transaction operation] e a v tx op 11 :user/name richhickey 1000 true 22 :user/name tonsky 1000 true 33 :user/name pithyless 2000 true
140. e a v tx op 11 :user/name richhickey 1000 true 22 :user/name tonsky 1000 true 33 :user/name pithyless 2000 true 99 :user/name awkay 3000 true Transactions · Assert
141. e a v tx op 11 :user/name richhickey 1000 true 22 :user/name tonsky 1000 true 33 :user/name pithyless 2000 true 22 :user/name tonsky 3000 false Transactions · Retract
142. e a v tx op 11 :user/name richhickey 1000 true 22 :user/name tonsky 1000 true 33 :user/name pithyless 2000 true 22 :user/name tonsky 3000 false 22 :user/name nikita 3000 true Transactions · Update
143. Reified Transactions e a v tx 33 :user/name pithyless 2000 2000 :db/txInstant 2018-03-… 2000 2000 :tx/author Norbert 2000 2000 :tx/source GitHub import … 2000
144. Reified Transactions e a v tx 33 :user/name pithyless 2000 2000 :db/txInstant 2018-03-… 2000 2000 :tx/author Norbert 2000 2000 :tx/source GitHub import … 2000
145. Reified Transactions e a v tx 33 :user/name pithyless 2000 2000 :db/txInstant 2018-03-… 2000 2000 :tx/author Norbert 2000 2000 :tx/source GitHub import … 2000
146. Reified Transactions e a v tx 33 :user/name pithyless 2000 2000 :db/txInstant 2018-03-… 2000 2000 :tx/author Norbert 2000 2000 :tx/source GitHub import … 2000
147. Time Traveling (as-of db 3000) (as-of db #inst “2018-03-16”) (since db #inst “2018-03-16”) (history db) (filter db #(not= :user/password (:a %))) (with db [{:user/name “awkay”}])
148. Time Traveling (as-of db 3000) (as-of db #inst “2018-03-16”) (since db #inst “2018-03-16”) (history db) (filter db #(not= :user/password (:a %))) (with db [{:user/name “awkay”}])
149. Time Traveling (as-of db 3000) (as-of db #inst “2018-03-16”) (since db #inst “2018-03-16”) (history db) (filter db #(not= :user/password (:a %))) (with db [{:user/name “awkay”}])
150. Time Traveling (as-of db 3000) (as-of db #inst “2018-03-16”) (since db #inst “2018-03-16”) (history db) (filter db #(not= :user/password (:a %))) (with db [{:user/name “awkay”}])
151. Time Traveling (as-of db 3000) (as-of db #inst “2018-03-16”) (since db #inst “2018-03-16”) (history db) (filter db #(not= :user/password (:a %))) (with db [{:user/name “awkay”}])
152. Time Traveling (as-of db 3000) (as-of db #inst “2018-03-16”) (since db #inst “2018-03-16”) (history db) (filter db #(not= :user/password (:a %))) (with db [{:user/name “awkay”}])
153. Components e a v 66 :repo/slug tonsky/datascript 110 :commit/sha aaaaaa 110 :commit/title Release 0.16.2 110 :commit/email tonsky@me.com 66 :git/commits 110 {:repo/slug “tonsky/datascript" :git/commits [{:commit/sha "aaaaaa" :commit/title "Release 0.16.2" :commit/email "tonsky@e.com"}]}
154. Components e a v 66 :repo/slug tonsky/datascript 110 :commit/sha aaaaaa 110 :commit/title Release 0.16.2 110 :commit/email tonsky@me.com 66 :git/commits 110 {:repo/slug “tonsky/datascript" :git/commits [{:commit/sha "aaaaaa" :commit/title "Release 0.16.2" :commit/email "tonsky@e.com"}]}
155. Components {:repo/slug "clojure/clojure" :git/commits [{:commit/sha "bbbbbb" :commit/title "Release 1.8.0" :commit/email "rich@e.com"} {:commit/sha "cccccc" :commit/title "Release 1.9.0” :commit/email "rich@e.com"} {:commit/sha "dddddd" :commit/title "Fix bugs" :commit/email “stuart@e.com"}]} e a v 55 :repo/slug clojure/clojure 120 :commit/sha bbbbbb 120 :commit/title Release 1.8.0 120 :commit/email rich@e.com 55 :git/commits 120 130 :commit/sha cccccc 130 :commit/title Release 1.9.0 130 :commit/email rich@e.com 55 :git/commits 130 140 :commit/sha dddddd 140 :commit/title Fix bugs 140 :commit/email stuart@e.com 55 :git/commits 140
156. Components {:repo/slug "clojure/clojure" :git/commits [{:commit/sha "bbbbbb" :commit/title "Release 1.8.0" :commit/email "rich@e.com"} {:commit/sha "cccccc" :commit/title "Release 1.9.0” :commit/email "rich@e.com"} {:commit/sha "dddddd" :commit/title "Fix bugs" :commit/email “stuart@e.com"}]} e a v 55 :repo/slug clojure/clojure 120 :commit/sha bbbbbb 120 :commit/title Release 1.8.0 120 :commit/email rich@e.com 55 :git/commits 120 130 :commit/sha cccccc 130 :commit/title Release 1.9.0 130 :commit/email rich@e.com 55 :git/commits 130 140 :commit/sha dddddd 140 :commit/title Fix bugs 140 :commit/email stuart@e.com 55 :git/commits 140
157. Components {:repo/slug "clojure/clojure" :git/commits [{:commit/sha "bbbbbb" :commit/title "Release 1.8.0" :commit/email "rich@e.com"} {:commit/sha "cccccc" :commit/title "Release 1.9.0” :commit/email "rich@e.com"} {:commit/sha "dddddd" :commit/title "Fix bugs" :commit/email “stuart@e.com"}]} e a v 55 :repo/slug clojure/clojure 120 :commit/sha bbbbbb 120 :commit/title Release 1.8.0 120 :commit/email rich@e.com 55 :git/commits 120 130 :commit/sha cccccc 130 :commit/title Release 1.9.0 130 :commit/email rich@e.com 55 :git/commits 130 140 :commit/sha dddddd 140 :commit/title Fix bugs 140 :commit/email stuart@e.com 55 :git/commits 140
158. Entity (q [:find ?repo :where [11 :repo/slug ?repo]] db)
159. Entity (q [:find ?repo ?sha :where [11 :repo/slug ?repo] [11 :repo/commits ?c] [?c :commit/sha ?sha]] db)
160. Entity (q [:find ?repo ?sha ?title :where [11 :repo/slug ?repo] [11 :repo/commits ?c] [?c :commit/sha ?sha] [?c :commit/title ?title]] db)
161. Entity (def rich (entity db 11)) (:repo/slug rich) (map :commit/sha (:repo/commits rich))
162. Entity (def rich (entity db 11)) (:repo/slug rich) (map :commit/sha (:repo/commits rich))
163. Entity (def rich (entity db 11)) (:repo/slug rich) (map :commit/sha (:repo/commits rich))
164. Pull API [:find (pull ?e query) :where [?e :repo/slug “clojure/clojure”]]
165. Pull API [:find (pull ?e query) :where [?e :repo/slug “clojure/clojure”]] [:repo/slug :repo/langs {:repo/owner [:user/name :org/name {:repo/_owner [(:repo/langs :limit 1) {:repo/commits [:commit/sha]}]}]}] [{:repo/slug "clojure/clojure" :repo/langs ["clojure" "java"] :repo/owner {:org/name "clojure" :repo/_owner [{:repo/langs ["clojure"] :repo/commits [{:commit/sha "bbbbbb"} {:commit/sha "cccccc"} {:commit/sha “dddddd"} ]}]}}]
166. Pull API [:find (pull ?e query) :where [?e :repo/slug “clojure/clojure”]] [:repo/slug :repo/langs {:repo/owner [:user/name :org/name {:repo/_owner [(:repo/langs :limit 1) {:repo/commits [:commit/sha]}]}]}] [{:repo/slug "clojure/clojure" :repo/langs ["clojure" "java"] :repo/owner {:org/name "clojure" :repo/_owner [{:repo/langs ["clojure"] :repo/commits [{:commit/sha "bbbbbb"} {:commit/sha "cccccc"} {:commit/sha “dddddd"} ]}]}}]
167. Pull API [:find (pull ?e query) :where [?e :repo/slug “clojure/clojure”]] [:repo/slug :repo/langs {:repo/owner [:user/name :org/name {:repo/_owner [(:repo/langs :limit 1) {:repo/commits [:commit/sha]}]}]}] [{:repo/slug "clojure/clojure" :repo/langs ["clojure" "java"] :repo/owner {:org/name "clojure" :repo/_owner [{:repo/langs ["clojure"] :repo/commits [{:commit/sha "bbbbbb"} {:commit/sha "cccccc"} {:commit/sha “dddddd"} ]}]}}]
168. Pull API [:find (pull ?e query) :where [?e :repo/slug “clojure/clojure”]] [:repo/slug :repo/langs {:repo/owner [:user/name :org/name {:repo/_owner [(:repo/langs :limit 1) {:repo/commits [:commit/sha]}]}]}] [{:repo/slug "clojure/clojure" :repo/langs ["clojure" "java"] :repo/owner {:org/name "clojure" :repo/_owner [{:repo/langs ["clojure"] :repo/commits [{:commit/sha "bbbbbb"} {:commit/sha "cccccc"} {:commit/sha “dddddd"} ]}]}}]
169. Pull API [:find (pull ?e query) :where [?e :repo/slug “clojure/clojure”]] [:repo/slug :repo/langs {:repo/owner [:user/name :org/name {:repo/_owner [(:repo/langs :limit 1) {:repo/commits [:commit/sha]}]}]}] [{:repo/slug "clojure/clojure" :repo/langs ["clojure" "java"] :repo/owner {:org/name "clojure" :repo/_owner [{:repo/langs ["clojure"] :repo/commits [{:commit/sha "bbbbbb"} {:commit/sha "cccccc"} {:commit/sha “dddddd"} ]}]}}]
170. Pull API [:find (pull ?e query) :where [?e :repo/slug “clojure/clojure”]] [:repo/slug :repo/langs {:repo/owner [:user/name :org/name {:repo/_owner [(:repo/langs :limit 1) {:repo/commits [:commit/sha]}]}]}] [{:repo/slug "clojure/clojure" :repo/langs ["clojure" "java"] :repo/owner {:org/name "clojure" :repo/_owner [{:repo/langs ["clojure"] :repo/commits [{:commit/sha "bbbbbb"} {:commit/sha "cccccc"} {:commit/sha “dddddd"} ]}]}}]
171. Pull API [:find (pull ?e query) :where [?e :repo/slug “clojure/clojure”]] [:repo/slug :repo/langs {:repo/owner [:user/name :org/name {:repo/_owner [(:repo/langs :limit 1) {:repo/commits [:commit/sha]}]}]}] [{:repo/slug "clojure/clojure" :repo/langs ["clojure" "java"] :repo/owner {:org/name "clojure" :repo/_owner [{:repo/langs ["clojure"] :repo/commits [{:commit/sha "bbbbbb"} {:commit/sha "cccccc"} {:commit/sha “dddddd"} ]}]}}]
172. Pull API [:find (pull ?e query) :where [?e :repo/slug “clojure/clojure”]] [:repo/slug :repo/langs {:repo/owner [:user/name :org/name {:repo/_owner [(:repo/langs :limit 1) {:repo/commits [:commit/sha]}]}]}] [{:repo/slug "clojure/clojure" :repo/langs ["clojure" "java"] :repo/owner {:org/name "clojure" :repo/_owner [{:repo/langs ["clojure"] :repo/commits [{:commit/sha "bbbbbb"} {:commit/sha "cccccc"} {:commit/sha “dddddd"} ]}]}}]
173. And now for something completely different
174. Event Sourcing 
175. Datomic
176. Datomic
177. Datascript
178. Pull API Ȑ
179. Pull API 
180. Appendices
181. Parameterized Query [:find ?name :where [11 :user/name ?name]]
182. Parameterized Query · Database (q [:find ?name :where [11 :user/name ?name]] (db conn))
183. Parameterized Query · Database (q [:find ?name :in $ :where [11 :user/name ?name]] (db conn))
184. Parameterized Query · Template (q [:find ?name :in $ ?id :where [?id :user/name ?name]] (db conn) 11)
185. Parameterized Query · Template (q [:find ?name :in $ [?id ...] :where [?id :user/name ?name]] (db conn) [11 22 33])
186. Parameterized Query · Template (q [:find ?name :in $ ?id ?name :where [?id :user/name ?name]] (db conn) 11 “richhickey”)
187. Parameterized Query · Rules (q [:find ?name :in $ % :where [(repo-owner ?p ?name)]] db [[(repo-owner ?p ?name) [?p :org/name ?name]] [(repo-owner ?p ?name) [?p :user/name ?name]]])
188. Parameterized Query · Database (q [:find ?name (count ?id) :where [?id :user/name ?name] [?id :user/stars _] (since (db conn) #inst “2018-03-01”))
189. Parameterized Query · Database (q [:find ?name (count ?id) :in $db $since :where [$db ?id :user/name ?name] [$since ?id :user/stars _] (db conn) (since (db conn) #inst “2018-03-01”)
190. Parameterized Query · Aggregates (q [:find (avg ?age) :where [_ :user/age ?age] (db conn))
191. Parameterized Query · Aggregates (q [:find (avg ?age) :with ?e :where [?e :user/age ?age] (db conn))
192. {:db-before {:database-id "58a47389-f1ab-4d81-85b6-715cecde9bac", :t 1000, :next-t 1001, :history false}, :db-after {:database-id "58a47389-f1ab-4d81-85b6-715cecde9bac", :t 1001, :next-t 1005, :history false}, :tx-data [ #datom[13194139534317 50 #inst “2017-02-15T19:28:52.270-00:00" 13194139534317 true] #datom[17592186045422 63 "The Goonies" 13194139534317 true] #datom[17592186045422 64 "action/adventure" 13194139534317 true] #datom[17592186045422 65 1985 13194139534317 true] #datom[17592186045423 63 "Commando" 13194139534317 true] #datom[17592186045423 64 "action/adventure" 13194139534317 true] #datom[17592186045423 65 1985 13194139534317 true] ], :tempids {-9223301668109598138 17592186045422, -9223301668109598137 17592186045423, -9223301668109598136 17592186045424}} Transaction Report
193. Graph BFS https://hashrocket.com/blog/posts /using-datomic-as-a-graph-database
194. Sort ?
195. Sort (let [initial (q [:find ?e ?c :where [?e :repo/slug ?c]] db) sorted (map first (sort-by second initial)) result (pull-many db ‘[*] sorted)] result)
196. Sort (let [initial (q [:find ?e ?c :where [?e :repo/slug ?c]] db) sorted (map first (sort-by second initial)) result (pull-many db ‘[*] sorted)] result)
197. Sort (let [initial (q [:find ?e ?c :where [?e :repo/slug ?c]] db) sorted (map first (sort-by second initial)) result (pull-many db ‘[*] sorted)] result)
198. Performance * :db/noHistory * clause order
199. Performance * :db/noHistory * clause order
200. Armchair Philosophy * schema change (accrete) * global unique keywords * data immutability
201. Armchair Philosophy * schema change (accrete) * global unique keywords * data immutability
202. Armchair Philosophy * schema change (accrete) * global unique keywords * data immutability
203. Fini bit.ly/datalog-gist