ermouth

100M docs? Of json format? On commodity hardware? In 2003?

Hahaha, hello long waited friend from parallel universe!

I'm talking about the internals of couchjs.

_list functions stream, and was specifically designed to be able to stream. However, streaming does not help much in this case, moreover too small chunks dramatically reduce already awful _list perf.

Taking this in account I see no value for views to stream. Sending all emitted KVs for the doc to Erlang bits in one turn seems both much more predictable and safe.

Multiple CVEs have been reported including a full RCE, which was patched in later versions

Last CVEs has nothing to do with Spidermonkey. BTW they may be patched without upgrade, with 5LOC long design document in Erlang.

The main reason of last CVEs is inconsistency in parsing improper JSONs by Erlang parser. Namely, most JSON parsers process '{"abc":1, "abc":2}' as {abc:2}, but old jiffy parses it as {abc:1}. BTW severe inconsistencies in parsing JSON are pretty common across implementations, please read http://seriot.ch/parsing_json.php for more details.

Citation needed. There's an issue specifically about this in the CouchDB issue tracker if you'd like to read more.

I‘ll give you no cite, sorry, because we discovered the effect during internal tests. Reason is simple: accessing values in deep branchy JSONs is generally faster in JS, because it‘s native format. JSON in Erlang is a monster like {[{<<"abc">>, 1}]} for {abc:1}, which, when has a lot of levels and nodes at each level, performs bad for selecting random node.

Curious what kind of database sizes you're working with too

We sometimes measure number of docs with M postfix ) Not very often, however. In my humble opinion, if you plan to have CouchDB with, say, 100M docs in a single bucket, you probably chose wrong solution.

BTW, same for large kitchen DBs for buckets with, say, 10K docs.

Nothing is streaming

Except CouchDB entire REST API, where nearly every endpoint streams result row by row, which is great.

Performance (and likely security, due to age of the engine) in this subsystem is extremely poor

As of security: wrong guess. Go compare number of critical CouchDB CVE for last, say, 5 years, with any other DB you want.

As for query server: indexing is slow for the reasons you pointed out. Requesting persisted index is ok. Taking in account CouchDB persists everything, it‘s not in-memory DB (which is again great), I‘d say it‘s even fast.

Performance in this (Erlang) area also appeared to be proportional to the code size of the map function

Performance in this area depends much more on how branchy is the json doc being processed. It‘s not about CouchDB itself, it‘s about json parser used. There might be a situation when you have better perf using JS views.

Nothing about this is relaxing.

Indeed. But then it just works, for years, with zero maintenance even for replications – the result I‘ve never even nearly achieved with any other DB I used.

Server-side ACL filtering without affecting CouchDB native API can be achieved using https://github.com/ermouth/covercouch

1) In fact, versions up to 1.0 supported IE8. Think current version also support, although it was not tested in IE8. To mention – $.my is heavily and primarily used in biz environment for very complex backends.

2) Forms can even be recursive. http://cloudwall.me/etc/json-editor.html – you can check youself how deep source json and associated forms can go and find out when it will stall )

You can not use one Angular app inside other without side effects and tuning. So Angular app in general can not be a control (like input or select) for another app.

$.my apps behave like complex controls – you can enclose one $.my app into other, you even can make this enclosure recursive (for example http://cloudwall.me/etc/json-editor.html).

Also since $.my manifests are JSON docs, you can combine them just attaching one manifest as a property of another manifest – so app of nearly any complexity can exist as a single JSON.

Well... I did not use word "declarative" anywhere at jquerymy.com – but if someone think $.my manifests are declarative, I understand why.

Can you tell, why do you think this syntax is not declarative? What is your interpretation?

You can try cloudwall.me on iPad to be convinced )

Well, it‘s a DOM animation lag mostly. Thanks for your point althouth.