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postgresqljsonb

how to get from jsonb subJesonb by key array in postgres

I have jsonb field and array keys how get sub jsonb

field = {"f1":1, "f2":null, "f3":"fff", "f4":"4"}

kes = ["f1", f3]

We need to get: {"f1":1, "f3":"fff"}

Solution

  • You could unnest both, join the results and aggregate back:

    Something like: 

    select jsonb_object_agg(i.k, i.v)
from jsonb_each('{"f1":1, "f2":null, "f3":"fff", "f4":"4"}'::jsonb) as i(k,v)
  join jsonb_array_elements_text('["f1", "f3"]') t(k) on t.k = i.k