1. MQL-to-SQL a JSON-based query language for RDBMS data access from AJAX applications

3. Ex-MySQL, ex-Sun Microsystems

4. Web & BI developer at Strukton Rail

8. What's wrong with SQL?

9. The Metaweb Query Language (MQL)

10. MQL-to-SQL

11. Demo

12. Questions

14. What's wrong with SQL?

15. The Metaweb Query Language (MQL)

16. MQL-to-SQL

17. Demo

18. Questions

22. Disadvantage: controlled=limited

26. What's wrong with SQL?

27. The Metaweb Query Language (MQL)

28. MQL-to-SQL

29. Demo

30. Questions

32. expressive syntax

33. declarative

34. designed for the RDBMS

35. portable

36. well supported

38. SELECT f.title , f.description , f.release_year , f.length , f.rating , a.first_name , a.last_name , l.name FROM film f INNER JOIN language l ON f.language_id = l.id LEFT JOIN film_actor fa ON f.id = fa.film_id LEFT JOIN actor a ON fa.actor_id = a.id SQL not declarative enough Spoken in Has cast Starring in

39. SELECT f.title , f.description , f.release_year , f.length , f.rating , a.first_name , a.last_name , spoken_in.name FROM film f RELATE spoken_in language l , has_cast film_actor fa RELATE starring_in actor a SQL not declarative enough Spoken in Has cast Starring in

40. SQL can't escape the RM Unnormalized data Split off – multivalued attributes – repeating groups First normal form (1NF) Higher normal forms (>= 3NF) Remove redundancy Denormalized data (1NF) SQL queries: – JOIN operation ??? Header – line 1a – line 2b header line 1a line 2b header 1 2 line 1a line 2b header line 1a header line 2b

41. SQL can't escape the RM

42. SELECT f.* , l.*, ol.* , (SELECT * FROM film_category fc INNER JOIN category c ON fc.category_id = c.id WHERE fc.film_id = f.film_id) , (SELECT * FROM film_actor fa INNER JOIN actor a ON fa.actor_id = a.id WHERE fa.film_id = f.film_id) FROM film f INNER JOIN language l ON f.language_id = l.id INNER JOIN language ol ON f.original_language_id = ol.id SQL can't escape the RM

43. SELECT f.* , l.*, ol.* , c.*, a.* FROM film f INNER JOIN language l ON f.language_id = l.id INNER JOIN language ol ON f.original_language_id = ol.id LEFT JOIN film_category fc ON f.id = fc.film_id LEFT JOIN category c ON fc.category_id = c.id LEFT JOIN film_actor fa ON f.id = fa.film_id LEFT JOIN actor a ON fa.actor_id = a.id SQL can't escape the RM

46. ACID

49. What's wrong with SQL?

50. The Metaweb Query Language (MQL)

51. MQL-to-SQL

52. Demo

53. Questions

58. http://api.freebase.com/api/service/mqlread? queries ={"q1": {"query":[{ Your MQL here }]}, "q2": {"query":[{ Your MQL here }]}}

59. http://api.freebase.com/api/service/mqlwrite

61. Scalar: boolean, null, number, string

62. Array: list of values { "type" : "/sakila/film" , "film_id" : 1 , "title" : "ACADAMY DINOSAUR" , "language" : { "language_id" : 1 , "language_name" : "English" } , "category" :[ "Action" , "Adventure" ] }

67. Finds objects matching the template

70. Value placeholders return data

73. Single- or multi-valued (array)

78. Can't specify join conditions

80. Explicit operators for advanced filters

83. Operations not returned in the result

86. return: count

87. cursor

88. * wildcard

90. What's wrong with SQL?

91. The Metaweb Query Language (MQL)

92. MQL-to-SQ L

93. Demo

94. Questions

96. MySQL, PostgreSQL, SQLite, Oracle

97. http://code.google.com/p/mql-to-sql

98. GPL

99. Lacks many features, has many bugs

100. don't use in hospitals and airplanes

102. MQL type maps to a SQL table

105. MQL-to-SQL index.php config.php <?php include 'config.php' ; ...code... ?> <?php $connection_file_name = ''; $metadata_file_name = ''; ?>

106. MQL-to-SQL metadata file { &quot;domains&quot; : { &quot;sakila&quot; : { &quot;schema_name&quot; : &quot;&quot; , &quot;types&quot; : { &quot;actor&quot; : { &quot;properties&quot; : { &quot;actor_id&quot; : { &quot;column_name&quot; : &quot;actor_id&quot; , &quot;nullable&quot; : false , &quot;type&quot; : &quot;/type/int&quot; }, &quot;starring_in&quot; : { &quot;type&quot; : &quot;/sakila/film_actor&quot; , &quot;direction&quot; : &quot;referenced<-referencing&quot; , &quot;join_condition&quot; : [ { &quot;referencing_column&quot; : &quot;actor_id&quot; , &quot;referenced_column&quot; : &quot;actor_id&quot; },

108. What's wrong with SQL?

109. The Metaweb Query Language (MQL)

110. MQL-to-SQL

111. Demo

112. Questions

114. What's wrong with SQL?

115. The Metaweb Query Language (MQL)

116. MQL-to-SQL

117. Demo

118. Questions

121. MySQL plugin?

123. Online query editor