> On Feb 21, 2020, at 4:20 AM, Wout Mertens <wout.mert...@gmail.com> wrote: > > In JavaScript, objects are key-value collections with unique keys, where the > order of the keys is important.
JSON is not JavaScript. The order of keys is NOT significant in JSON, and many, many JSON implementations parse JSON objects into data structures* that do not preserve key order. Clients using such implementations cannot determine the original order of keys, nor can they re-serialize the object with the same ordering. I have run into multiple issues over time with systems that assume JSON key ordering is significant and preserved (CouchDB and Scuttlebutt come to mind), which then later have to redesign protocols or data schema because of interoperability problems this causes. —Jens * The platform's standard "dictionary" / "map" class is typically implemented as a hash table or binary tree, as in Java, .NET, Objective-C, Swift, Go, Lua, C++. (I'm unsure about Python and Ruby.) A few platforms besides JS keep an auxiliary key array to preserve ordering. Erlang uses a linked-list, which is ordered. _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
