Hstore Query to find records matching with any array element using ruby on rails

Question

I've a hstore field in a database table. I want to write a Query to find records matching with any array element in any hash of hstore field using ruby on rails.

 Users Table
 --------------------------------------------------------------------------------
        ID    Name    sectors(hstore) 

        1     Piotr   {"aviation"=>"0", "oil_and_gas" => "50", "transport" => "50"}
        2     reza    {"oil_and_gas" => "70", "energy" => "30"}
        3     pat     {"transport" => "40", "energy" => "60"}
        4     Kim     {"infrastructure" => "20", "healthcare" => "20", "industrial" => "60"}

considering above test data, I want to write a query on hstore field to get all records having any key like ['oil_and_gas', 'energy', 'transport']

I can match and find single sector records as its mentioned in https://nandovieira.com/using-postgresql-and-hstore-with-rails, but my requirement is to find any record where hstore hash is having any one key matching with any one element of array.

I'm using Rails 5.1.6.2, ruby 2.5.3

Answer 1

May be you are looking for the following operator:

hstore ? key # does hstore contain key?

Query may looks like so:

User.where("sectors ? 'oil_and_gas'")
    .or("sectors ? 'energy'")
    .or("sectors ? 'transport'")

According to postgresql docs

Check for a specific key in hstore column You can check for a specific key in an hstore column using the ? operator in the WHERE clause. For example, the following statement returns all rows with attr contains key publisher.

SELECT
  title,
  attr->'publisher' as publisher,
  attr
FROM
  books
WHERE
  attr ? 'publisher';