Add postgres hstore post

content/posts/2015-08-05-postgresql-error-type-hstore-does-not-exist.md

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+date = "2015-08-05"
+title = "Postgresq error: type 'hstore' does not exist"
+tags = ["postgresql"]
+description = "When importing a postgres dump into a clean database I got an error about type 'hstore' not existing. This is how your fix that."
+slug = "postgresql-error-type-hstore-does-not-exist"
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+
+Today I was programming and messed up my database schema in such a way that I just wanted to restore a recent backup and start over from there.
+
+    dropdb app_development
+    createdb app_development
+    
+Unfortunately I ran into an error:
+
+> PostgreSQL error: type 'hstore' does not exist
+
+hstore is a Postgresql extension (available since postgresql-9.x) that allows you store sets of key/value pairs within a single Postgresql value (read column). Read more on hstore in the [Postgresql documentation][1].
+
+Anyway, the hstore extension is not loaded for my brand new database. No problem, simply add it with this command:
+
+    psql app_development -c 'create extension hstore;'
+
+That's all.
+
+## Bonus points
+
+If you use hstore for almost any database, you could add it to the `template1` database. 
+
+FYI: Postgresql creates a new databases by copying another. `template1` is a default database provided by Postgresql for the purpose of creating new database.
+
+Adding hstore to `template1` is just as easy as adding it to your own database.
+
+    psql template1 -c 'create extension hstore;'
+    
+Whenever your use `createdb` now, the new database will have the hstore extension by default.
+
+[1]: http://www.postgresql.org/docs/9.0/static/hstore.html