Re: Record counts...

From: Bryan Lewis (brya..aine.rr.com)
Date: Mon May 29 2006 - 08:04:22 EDT

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    This might help:

    http://objectstyle.org/confluence/display/CAYDOC/Customizing+Queries

    Borut Bolčina wrote:

    > Hi,
    >
    > is this already implemented in some generic utility class?
    >
    > -Borut
    >
    > On 14.6.2005 23:03, Andrus Adamchik wrote:
    >
    >>No, SQLTemplate is actually used to run arbitrary SQL. In some cases the
    >>result can be mapped to an entity, but in most it will be just that - a
    >>list of Map objects with each Map corresponding to a result set data. So a
    >>count query would look like this:
    >>
    >> String sql = "SELECT COUNT(*) FROM SOME_TABLE"
    >> DataMap queryRoot =
    >>context.getEntityResolver().getDataMap("data_map_name");
    >> SQLTemplate query = new SQLTemaplate(queryRoot, sql, true);
    >> Map singleRow = (Map) context.performQuery(query).get(0);
    >> Number count = (Number) singleRow.values().next();
    >>
    >>As this is a bit too verbose, 1.2 will likely encapsulate this code in a
    >>generic utility class. For now you can create your own.
    >>
    >>Andrus
    >>
    >>
    >>
    >>
    >>
    >>>I read through that documentation, but it doesn't really appear to do
    >>>anything different then the normal SelectQuery besdies being able to
    >>>write it in SQL. I was wanting to do something like SELECT COUNT(*)
    >>>FROM Object and just got the int result, with out loading all the
    >>>child records etc.
    >>>
    >>>Just reading the docs there it doesn't appear to let me do something like
    >>>that.
    >>>
    >>>-Nick
    >>>
    >>>On 6/14/05, Mike Kienenberger <mkienen..laska.net> wrote:
    >>>
    >>>
    >>>>Nick Stuart <nicholas.stuar..mail.com> wrote:
    >>>>
    >>>>
    >>>>>This should be an easy one. I basically just want to find out how many
    >>>>>objects of a certain type there are. Easy to do with a SelectQuery and
    >>>>>user List.size() but does the cause any kind of performance issues?
    >>>>>Just thinking if these objects have child objects, which has more
    >>>>>child objects, will it pull all those when I Select the parent?
    >>>>>
    >>>>>
    >>>>If you only want the count and don't want to load any objects, just use
    >>>>SQLTemplate.
    >>>>
    >>>>http://www.objectstyle.org/cayenne/userguide/fetch/sqltemplate.html
    >>>>
    >>>>
    >>>>
    >>
    >>
    >>
    >
    > --
    > bLOG <http://www.delo.si/blog/borutb/>
    > --
    > Naključna *izjava tedna* iz tednika Mladina:



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