ruby - Rails hStore postgresql activerecord database query? -

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i want able query hstore column on pg database , return values corresponding specific key.

the data looks this: (keep in mind :data postgresql hstore)

[ id: 2, data: {"tags"=>"ruby, objects", "type"=>"video", "title"=>"rubytapas: blocks, procs, , lambdas"},    id: 3, data: {"tags"=>"javascript, objects", "type"=>"video", "title"=>"rubytapas: blocks, procs, , lambdas"} ]

i want effect of this:

model.uniq.pluck(:tags)

and output expect is:

ruby, objects, javascript

*i strictly trying implement activerecord , postgresql.

i able desired result doing:

model.pluck(:data).map{|j| j['tags'].split(',') }.flatten.uniq

i still interested in solution doesn't require map on activerecord relation. please advise.


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