How to search multiple items in JSON array in Postgres 9.3 - json

Question

I have scenario where i need to search multiple values in a JSON array. Below is my schema.
ID DATA
1 {"bookIds" : [1,2,3,5], "storeIds": [2,3]}
2 {"bookIds" : [1,2], "storeIds": [1,3]}
3 {"bookIds" : [11,12,10,9], "storeIds": [4,3]}
I want all the rows with value 1,2. Below is query i am using (This is query is written by one of fellow stackoverflow user Mr. klin credit to him).
select t.*
from JSONTest t, json_array_elements(data->'bookIds') books
where books::text::int in (1, 2);
However output I am duplicate rows in output, below is my output.
id data
1 {"bookIds" : [1,2,3,5], "storeIds": [2,3]}
1 {"bookIds" : [1,2,3,5], "storeIds": [2,3]}
2 {"bookIds" : [1,2], "storeIds": [1,3]}
2 {"bookIds" : [1,2], "storeIds": [1,3]}
I want only two rows in output that is id 1,2. How can i do that? I don't want use Distinct due to other constraints,
SQL Fiddle : http://sqlfiddle.com/#!15/6457a/2

Answer 1

Unfortunately there is no direct conversion function from a JSON array to a "real" Postgres array. (data ->'bookIds')::text returns something that is nearly a Postgres array literal: e.g. [1,2,3,5]. If you replace the [] with {} the value can be cast to an integer array. Once we have a proper integer array we can use the #> to test if it contains another array:
select *
from jsontest
where translate((data ->'bookIds')::text, '[]', '{}')::int[] #> array[1,2];
translate((data ->'bookIds')::text, '[]', '{}') will convert [1,2,3,5] to {1,2,3,5} which then is converted to an array using ::int[]
SQLFiddle: http://sqlfiddle.com/#!15/6457a/4