CREATE EXTENSION hstore getting error

Log:
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-- execute("CREATE EXTENSION hstore")
rake aborted!

StandardError: An error has occurred, this and all later migrations canceled:

PG::UndefinedFile: ERROR:  could not open extension control file "/usr/share/postgresql/9.1/extension/hstore.control": No such file or directory
: CREATE EXTENSION hstore/usr/local/rvm/gems/[email protected]/gems/activerecord-4.1.5/lib/active_record/connection_adapters/postgresql/database_statements.rb:128:in `async_exec'
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Solution:

If you have postgresql already installed then run below command

$ sudo apt-get install postgresql-contrib