Hannu Krosing-3 wrote > On 11/18/2013 06:49 PM, Josh Berkus wrote: >> On 11/18/2013 06:13 AM, Peter Eisentraut wrote: >>> On 11/15/13, 6:15 PM, Josh Berkus wrote: >>>> Thing is, I'm not particularly concerned about *Merlin's* specific use >>>> case, which there are ways around. What I am concerned about is that we >>>> may have users who have years of data stored in JSON text fields which >>>> won't survive an upgrade to binary JSON, because we will stop allowing >>>> certain things (ordering, duplicate keys) which are currently allowed >>>> in >>>> those columns. At the very least, if we're going to have that kind of >>>> backwards compatibilty break we'll want to call the new version 10.0. >>> We could do something like SQL/XML and specify the level of "validity" >>> in a typmod, e.g., json(loose), json(strict), etc. >> Doesn't work; with XML, the underlying storage format didn't change. >> With JSONB, it will ... so changing the typemod would require a total >> rewrite of the table. That's a POLS violation if I ever saw one > We do rewrites on typmod changes already. > > To me having json(string) and json(hstore) does not seem too bad.
Three things: 1) How would this work in the face of functions that erase typemod information? 2) json [no type mod] would have to effectively default to json(string)? 3) how would #1 and #2 interact? I pondered the general idea but my (admittedly limited) gut feeling is that using typemod would possibly be technically untenable and from an end-user perspective would be even more confusing than having two types. David J. -- View this message in context: http://postgresql.1045698.n5.nabble.com/additional-json-functionality-tp5777975p5779428.html Sent from the PostgreSQL - hackers mailing list archive at Nabble.com. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers