Re: TIP#308 Published: Tcl Database Connectivity (TDBC)

Dnia 16-11-2007 o 17:00:52 Donal K. Fellows
<donal.k.fellows@xxxxxxxxxxxxxxxx> napisał(a):
(5) The primitive function to retrieve a row needs to retrieve it as
a list, IM(NS)HO. This is the natural structure to represent ordered
data as retrieved from a DBMS, and avoids a bunch of overhead
involved in creating and then parsing out a dict.
No. That *really* screws with Tcl's value system.

I have to say I disagree here. A lot.

First of all, I think SQLite's syntax (flat list) really rocks:

foreach {id name value} [$db eval {SELECT id,name,value FROM table}] {
...
}

Also, a list of lists is a really useful construction. For example you can
pass that directly to tablelist widget, so all you do is call delete 0 end
and do an insertlist $result on it.

Also, I'm not sure if that changed in 8.5, but [lsort] doesn't talk to
dicts nicely - so sorting a list of lists would work much better than
getting dictionaries.

While I know dicts would be the most elegant way, I don't think they're
the fastest (in terms of performance) and most powerful ones.

I think that query results should be returned as:
- flat list
- list of lists
- list of dicts

--
Wojciech Kocjan
.

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