How to search array of objects RedisJson using RedisSearch

Question

i have added a json document into my redis db using JSON.set Below given is my Json SET command

{
 "books": [
{
  "title": "Peter Pan",
  "price": 8.95
},
{
  "title": "Moby Dick",
  "price": 12.99
}
]
}

JSON.SET myDoc $ '{"books": [{"title": "Peter Pan", "price": 8.95},{"title": "A Thousand Suns", "price": 8.15}, {"title": "Moby Dick", "price": 12.99}]}'

Now i want to search this specific array of objects to fetch me the records which have price greater and equal to 8

i have tried creating an index but it always return me 0 records Below given is my index

 FT.CREATE docIdx ON JSON SCHEMA $.myDoc.books.price AS price Numeric

Answer 1

in the way you propose the index, you're ignoring the array of elements that belong to the object book. One way could be:

FT.CREATE docIdx ON JSON SCHEMA $.myDoc.books[*].price AS price Numeric 

or

FT.CREATE docIdx ON JSON SCHEMA $.myDoc.books[0:].price AS price Numeric

another recommendation it's to use the prefix since all documents with the same prefix will be indexed by Redisearch.

Something like:

FT.CREATE docIdx PREFIX 1 myDoc ON JSON SCHEMA $.books[*].price AS price Numeric

Notice, since you are trying to match the condition within the same document when you search for your price condition (between 8 and 9), the result will be the entire document "myDoc" with all the books, since the "Peter Pan" and "A Thousand Suns" matches the query condition. Such as:

> FT.SEARCH docIdx "@price:[8 12]"
1) "1"
2) "myDoc"
3) 1) "$"
   2) "{\"books\":[{\"title\":\"Peter Pan\",\"price\":8.95},{\"title\":\"A Thousand Suns\",\"price\":8.15},{\"title\":\"Moby Dick\",\"price\":12.99}]}"