We'll cover the new Json generation functions, as well as jsonb, and when to use json, jsonb or hstore. We'll end by looking into the future to see what other json functionality might be coming, such as json mutation functions. The talk will present a survey of the current and coming state of json features, as well as a speculative look at what which be in the future beyond 9.4 Overview: * the new json generation functions, such as jsonbuildobject and jsonbuildarray and how they can be used to build up arbitrarily complex and non-rectangular json. * json_typeof() * jsonb, and its relation to json and nested hstore. * how jsonb is different from json, (e.g. object field ordering, treatment of duplicate field names and whitespace) * performance differences between json and jsonb * what's missing from json/jsonb? What should we work on for 9.5? Mutation functions have been suggested, Are there others?