SCHEMA INFERENCE FOR MASSIVE JSON DATASETS ! ! ParisBD 2017 " - - PowerPoint PPT Presentation
" SCHEMA INFERENCE FOR MASSIVE JSON DATASETS ! ! ParisBD 2017 " ! ! Mohamed-Amine Baazizi 1 , Houssem Ben Lahmar 2 , Dario Colazzo 3 , " Giorgio Ghelli 4 , Carlo Sartiani 5 " (1) Universit Pierre et Marie Curie, France
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(1) Université Pierre et Marie Curie, France (2) University of Stuttgart, Germany (3) Université Paris-Dauphine, France ! (4) Università di Pisa, Italy (5) Università della Basilicata, Italy "
1!
2!
Semistructured Data: "
XML and RDF: "
JSON: "
different data model, no account for structural variations, no scalability!
3!
4!
5!
each li is unique in a record!
{ "person": { "firstname": "John", "lastname": "Smith", "coordinates": [120 , 10 ] } }
6!
{ "person": { "firstname": Null + Str , ("lastname": Str ) ?, "coordinates": [Num * ] } }
7!
[ ... 123, “abc” …]
[ ... 879, Null…] [ ... {“lab”: 758 } ]
[ (Num+ Str + Null + {“lab”: Num} )*]
8!
[ ... 123, “abc” …]
[ ... 879, Null…] [ ... {“lab”: 758 } ]
[ (Num+ Str + Null + {“lab”: Num} )*] [ (Num+ Str )*] [ (Num+ Null)*] [ { “lab”:Num }* ]
9!
[ ... 123, “abc” …]
[ ... 879, Null…] [ ... {“lab”: 758 } ]
[ (Num+ Str + Null + {“lab”: Num} )*] [ (Num+ Str )*] [ (Num+ Null)*] [ { “lab”:Num }* ]
10!
Sound, commutative and associative!
11!
{ "person": { "firstname": Null + Str , ("lastname": Str ) ?, "coordinates": [(Num + Bool) * ] } }
{ "person": { "firstname": Null , "lastname": Str , "coordinates": [Num * ] } }
{ "person": { "firstname": Str, "coordinates": [Bool * ] } }
12!
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15!
16!
17!
Data, SIGMOD’16!
Document Type Descriptors from XML Documents, SIGMOD’00!
Databases, VLDB’97!
18!
Documents, ICDE’06!
NoSQL DataStores, BTW’15!
Stores, VLDB’15!
19!