Hi,
I have a container that holds objects of same type (user defined
class), where each object has multiple attributes. These objects have
primary key (similar to a database) formed by combination of two
attributes, but I want to support multiple views of data by looking at
different combination of attributes and in some cases I might want to
combine these. For instance, lets say the class has four attributes
a1,a2,a3,a4; and primary key is a1+a4, now I can construct a view that
has subset of objects of this class by doing a search on these objects
that have specific values for attribute a3, and this can give me back
multiple objects and I want to combine the objects that have same
value for a2 into one ; this looks like a classic database
implementation but I dont have real database in my case, instead I have
set of objects and the query I am doing is on these objects based on
combination of attributes of the class. Any pointers on how to do this
using STL classes would be appreciated. I am looking into using
associative containers.. Is this already implemented by someone? I dont
care too much about efficiency since I wont have more than 100 of these
objects...
Thanks,
Sunil.
10  5270 
Try a STL map type, keyed on an object that is a combination of a1 and
a4.
sunil wrote: I have a container that holds objects of same type (user defined
class), where each object has multiple attributes. These objects have
primary key (similar to a database) formed by combination of two
attributes, but I want to support multiple views of data by looking at
different combination of attributes and in some cases I might want to
combine these. For instance, lets say the class has four attributes
a1,a2,a3,a4; and primary key is a1+a4...
sqlite is trivial to install and run. It works off a data file and can do
arbitrarily complex SQL statements, such as joins.
--
Phlip http://c2.com/cgi/wiki?ZeekLand <-- NOT a blog!!!
sunil wrote: Hi,
I have a container that holds objects of same type (user defined
class), where each object has multiple attributes. These objects have
primary key (similar to a database) formed by combination of two
attributes, but I want to support multiple views of data by looking at
different combination of attributes and in some cases I might want to
combine these.
[...]
this looks like a classic database
implementation but I dont have real database in my case, instead I have
set of objects and the query I am doing is on these objects based on
combination of attributes of the class. Any pointers on how to do this
using STL classes would be appreciated. I am looking into using
associative containers.. Is this already implemented by someone? I dont
care too much about efficiency since I wont have more than 100 of these
objects...
Thanks,
Sunil.
Boost.MultiIndex library can do this sort of thing: http://www.boost.org/libs/multi_index/doc/index.html
Also there is relational Template Library (RTL) in boost sandbox: http://tinyurl.com/zwe2o
regards
Andy Little
On Tue, 09 May 2006 17:56:39 GMT, I waved a wand and this message
magically appeared from Roland Pibinger:
[ Boost stuff snipped ] Have you actually used one of those libraries?
All I got was a headache!
-- http://www.munted.org.uk
Take a nap, it saves lives.
Thank you all for input, I looked at boost multi-index library and they
seem to have done a nice job. I cannot use it though due to some
restrictions on third party software. I think I can implement for my
case using maps and multimaps.....
Sunil
sunil wrote: Thank you all for input, I looked at boost multi-index library and they
seem to have done a nice job. I cannot use it though due to some
restrictions on third party software.
Excuse me? Boost's license is free with no restrictions. Our lawyer just
recently approved it for our shrink-wrap and turn-key solutions.
Maybe your boss likes paying expensive programmers to sit around reinventing
wheels all day. How's your C++ compiler coming along?
--
Phlip http://c2.com/cgi/wiki?ZeekLand <-- NOT a blog!!! This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
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