1. Building REST API using SQL Server and JSON Functions

2. Jovan Popovic Program Manager Projects
Microsoft Development Center Serbia
Program Manager
JSON
T-SQL language
Temporal In-memory technologies
Intelligent Database. 
Projects

3. JSON Support in SQL Server Building REST API using SQL Server
Agenda
JSON Support in SQL Server Building REST API using SQL Server

4. JSON Support in SQL Server
Combining relational and semi-structured data

5. JSON in SQL Database

6. Combine relational and JSON dataID
Name
Type
Price
Tags
Data 1
Bike
399.99
[“promo”]
{“Gears”:20, “Weight”:9.5,”Gender”:”M”} 2
Helmet 7
120.99
[“promo”,”sales”]
{“Visor”:true, “WxDxH”: [32,26.4,22]} 3
Car 6
29,500
{“Doors”:4, “Seats”:5, “MPG”:29} 8
299.99
[“sales”]
{“Tyres”:[“300c”,”35C”],Weight”:9.5,”Gender”:”M”} 9
{“Doors”:2, “Seats”:2, “MPG”:35}
SELECT ProductID, Name, Tags, JSON_VALUE(Data, '$.Weight') FROM Product WHERE Type=1 AND JSON_VALUE(Data, '$.Gender') = 'F' ORDER BY Price, CAST(JSON_VALUE(Data, '$.Weight') as float)

7. Optimizing JSON Queries
select JSON_VALUE(Data, '$.Type') as Type, Color, AVG( cast(JSON_VALUE(Data, '$.ManufacturingCost') as float) ) as Cost from Product group by JSON_VALUE(Data, '$.Type'), Color having JSON_VALUE(Data, '$.Type') is not null order by JSON_VALUE(Data, '$.Type')

8. Index on JSON Data
select JSON_VALUE(Data, '$.Type') as Type, Color, AVG( cast(JSON_VALUE(Data, '$.ManufacturingCost') as float) ) as Cost from Product group by JSON_VALUE(Data, '$.Type'), Color having JSON_VALUE(Data, '$.Type') is not null order by JSON_VALUE(Data, '$.Type')
alter table product add Type AS JSON_VALUE(Data, '$.Type'), ManufacturingCost AS cast(JSON_VALUE(Data, '$.ManufacturingCost') as float) create index json_index on Product(Type, Color) include (ManufacturingCost)

9. Index on JSON Data
select JSON_VALUE(Data, '$.Type') as Type, Color, AVG( cast(JSON_VALUE(Data, '$.ManufacturingCost') as float) ) as Cost from Product group by JSON_VALUE(Data, '$.Type'), Color having JSON_VALUE(Data, '$.Type') is not null order by JSON_VALUE(Data, '$.Type')

10. SQL results as JSON
SELECT ProductID, Name, Price, Tags = JSON_QUERY(Tags), Data = JSON_QUERY(Data) FROM Product FOR JSON PATH ID
Name
Price
Tags
Data 15
Bike
100
[…]
{…} 16
Car
29000 17
BB Ba…
29,99 18
Blade
18.50 19
Helmet
41.99
[ {"ProductID":15,"Name":“Bike","Price":100,"Data":{"Type":"Part","MadeIn":“SRB"}}, {"ProductID":16,"Name":“Car","Price":29000,"Tags":["promo"],"Data":{"Cost":11.67,"Type":"Part"}}, {"ProductID":17,"Name":"BB Ball Bearing","Price":28.99,"Data":{"Cost": ,"Type":"Part"}}, {"ProductID":18,"Name":"Blade","Price":18.50,"Tags":["new"],"Data":{}}, {"ProductID":19,"Name":"Helmet","Price":41.99,"Tags":["promo"],"Data":{"Cost":30.65}} ]

11. JSON to result set
[ {"ProductID":15,"Name":“Bike","Price":100,"Data":{"Type":"Part","MadeIn":“SRB"}}, {"ProductID":16,"Name":“Car","Price":29000,"Tags":["promo"],"Data":{"Cost":11.67,"Type":"Part"}}, {"ProductID":17,"Name":"BB Ball Bearing","Price":28.99,"Data":{"Cost": ,"Type":"Part"}}, {"ProductID":18,"Name":"Blade","Price":18.50,"Tags":["new"],"Data":{}}, {"ProductID":19,"Name":"Helmet","Price":41.99,"Tags":["promo"],"Data":{"Cost":30.65}} ] ID
Name
Price
Tags
Data 15
Bike
100
[…]
{…} 16
Car
29000 17
BB Ba…
29,99 18
Blade
18.50 19
Helmet
41.99
SELECT * FROM OPENJSON WITH ( ProductID int, Name nvarchar(50), Price money, Type nvarchar(max) AS JSON, Data nvarchar(max) AS JSON)

12. Building REST API using SQL Server
Exchanging JSON data with client applications

13. Built for Web Applications
Web Browser
Web Server
Initial request
</>
Database
AJAX
T-SQL
JSON

14. REST API
REST End-point
Get data from
SQL Database

15. Returning JSON resultsId
Title
Data
Tags 1
Bike
{….}
[…] 2
Helmet
{ }
View Model
ORM
{ }

16. Importing JSON objectsId
Title
Data
Tags 1
Bike
{….}
[…] 2
Helmet
{ }
DTO
ORM
{ }

17. SQL Server Samples on GitHub
Product Catalog REST API

18. Data Access Component
var pipe = new QueryPipe(“connection string”); await pipe.Stream(“SELECT …. FOR JSON PATH”, Response.Body); var mapper = new QueryMapper(“connection string”); var json = await mapper.GetStringAsync(“SELECT …. FOR JSON PATH”); var cmd = new Command(“connection string”); await cmd.ExecuteNonQuery(“UPDATE …”);
Lightweight and simple
Handles connection
Error handling
Asynchronous library
.BeginReaderAsync()
.WriteAsync()
Callbacks
Open source

19. DEMO

20. Questions?
Jovan Popovic
@jovanpop_msft